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Adsorption

, Volume 25, Issue 3, pp 501–511 | Cite as

Structural, thermal and photocatalytic properties of composite materials SiO2/TiO2/C

  • Karolina KucioEmail author
  • Barbara Charmas
  • Sylwia Pasieczna-Patkowska
Open Access
Article
  • 180 Downloads

Abstract

In the study the mechanochemical treatment procedure was used to prepare composite materials based on SiO2 with the addition of TiO2 and carbon black as a carbon matter. The investigations were carried out at the three rotational speeds 300, 500 and 700 rpm. Thermal and structural characteristics of the composites were investigated using N2 adsorption, TG/DTG/DTA, SEM and FT-IR/PAS methods. The photocatalytic properties were evaluated by methylene blue degradation (Co = 1 × 10−5 mol L−1) at UV light. The obtained results show that the mechanochemical treatment at different rotational speeds causes intensive changes in the porous structure of the obtained materials. Thermal analysis proved that the obtained materials are characterized by significant thermal stability. The obtained composites have comparable photocatalytic properties with pure TiO2 despite the fact that in the composite only 5% of TiO2 is used.

Keywords

Mechanochemical treatment Composites Structural properties TiO2 Photocatalysis 

1 Introduction

The intensive development of industry caused a rapid increase in environmental pollution (Li et al. 2014). Water pollution caused, among others, by the presence of dyes from industry is a mass problem facing humans worldwide. Most often coloured wastewaters are removed from the industry related to the production of rubber, leather, textiles, cosmetics, paper and plastics (Wu et al. 2017; Haque et al. 2011). Many dyes are toxic, cancerogenic and mutagenic to aquatic organisms (O’Neill et al. 1999; Wu et al. 2017). Even a very small amount of dye in water is highly undesirable (Haque et al. 2011).

The use of conventional methods for dyes removal from water, such as ultrafiltration, adsorption and reverse osmosis does not often give satisfactory results (Rajeshwar et al. 2008). Therefore new technologies for wastewater treatment are still being sought. Heterogeneous photocatalysis is included to advanced oxidation processes and plays a significant role in wastewater treatment. (Rajeshwar et al. 2008; Chong et al. 2010). In order to conduct a heterogeneous reaction five steps have to be taken. First, there must be diffusion of reagents to the surface (1). Then the reagents adsorb on the surface (2) and the reaction (3) proceedes on it. After these stages desorption (4) and diffusion (5) of products from the surface take place (Pirkanniemi and Sillanpää 2002; Herrmann 1999).

For photocatalytic degradation of dyes, the semiconductors (for instance metal oxides or metal sulphides) and their composites are often used (Fu et al. 1996; Zhang and Guo 2013; Ghorai et al. 2011). The most commonly used photocatalyst is titanium dioxide. This oxide is characterized by low cost, non-toxicity, chemical stability and long durability (Mills and Le Hunte 1997; Yin et al. 2003; Nakata and Fujishima 2012). It is not hazardous for the environment and humans (Van Gerven et al. 2007). TiO2 occurs in three polymorphic forms in nature: anatase, rutile and brookite (Zhang and Banfield 2000). Most often only anatase and rutile are used as photocatalysts (Yin et al. 2003). TiO2 has a wide band gap (3.2 eV for anatase and 3.0 for rutile) and therefore it is characterized by high photocatalytic activity in UV light (Hanaor and Sorrell 2011; Zhao et al. 2010; Zhang et al. 1997).

There are many methods for producing photocatalysts, e.g.: co-precipitation (Martinez-de La Cruz and Garcia Perez 2010; Yu et al. 2009; Zhang et al. 2005), sol–gel (Anderson and Bard 1997; Gao et al. 2009; Wu and Chen 2004; Yu et al. 2000) and hydrothermal methods (Fu et al. 2006; Kim et al. 2007; Yu and Kudo 2006). They are characterized by large consumption of energy and solvents constituting the reaction medium. Photocatalyst preparation processes usually generate high temperatures and pressures and a lot of waste products which can be dangerous for the environment (Molchanov and Buyanov 2001).

One of the methods of obtaining photocatalysts that does not result in environmental hazards is mechanochemistry (Jalalah et al. 2013; Carneiro et al. 2014). It gives the possibility of preparation of high-performance photocatalytic systems and creation of new physicochemical properties of various types of materials (Molchanov and Buyanov 2001). The mechanochemical processes are therefore in line with the principles of green chemistry introduced by Anastas (Anastas and Kirchhoff 2002). The energy generated during the collisions of the grinding balls is so high that it creates new chemical bonds between the substrates. Mechanochemical treatment in high energy mills enables the design of many compounds with different properties, including photocatalytic ones. In addition, it does not require the use of solvents, and thus reduces or completely eliminates the production of waste products (Kucio and Charmas 2018).

The aim of this paper was preparation and characterization of the composite materials characterized by photocatalytic properties using the mechanochemical method. The composites were based on SiO2 (matrix), TiO2 (photocatalytic component) and carbon black (adsorbent). Their applicability was tested using methylene blue in the range of UV light.

2 Experimental

2.1 Materials

The initial materials used in the research were TiO2 (POCH, Poland), synthetic amorphous SiO2 (SIPERNAT 50, Degussa, Germany) and carbon black (Gryfskand, Poland) as a carbon source.

2.2 Mechanochemical treatment (MChT)

The mechanochemical treatment was carried out using a planetary ball mill Pulverisette 7 (Fritsch, Germany). Four series of samples were prepared in the air atmosphere at rotational speeds (300, 500 and 700 rpm): (1) TiO2 (after MChT designated as T-300, T-500 and T-700); (2) SiO2 (designated as S-300, S-500 and S-700); (3) SiO2 with the addition of TiO2 (5%) (ST-300, ST-500 and ST-700); (4) SiO2 with the addition of TiO2 (5%) and carbon black (1%) (STC-300, STC-500 and STC-700). The mass ratio of the balls to the powder was 23:1 for the SiO2 series, 6.6:1 for the TiO2 series, 22:1 for the SiO2–TiO2 series and 22:1 for SiO2–TiO2–C series. MChT was carried out for 60 min (four cycles × 15 min, 5-min breaks were between the 15-min cycles). The container (80 cm3) and 250 balls of 5 mm diameter (total mass of 92.5 g) were manufactured from zirconium oxide, ZrO2. During the milling the temperature and pressure values were registered using the EASY GTM software (Fritsch, Germany). After MChT only the T-series had a coarse-grained consistency and the others were fine-grained.

2.3 Determination of bulk density

An analytical scale and a measuring cylinder (10 cm3) were used to determine the bulk density (ρ). Approximately 5 cm3 of each of the studied samples was precisely weighed and next the cylinder was tapped ten times against the background to spread the material evenly. Next the volume of the samples was read. The operation was repeated three times. The bulk density was calculated on the basis of the formula 1:
$$\rho ={\text{m/V}}$$
(1)
where m—the sample weight [g], V—the volume of the sample [cm3].

2.4 Nitrogen adsorption/desorption

In order to determine the structural parameters of the obtained samples, the method of low-temperature nitrogen adsorption/desorption (77.4 K) was used. The isotherms were recorded using a Micromeritics ASAP 2405N (USA) adsorption analyzer. Based on the obtained data the specific surface area SBET (BET equation at p/p0 between 0.06 and 0.2, where p and p0 are the equilibrium and saturation pressures of nitrogen, respectively), the micropore surface [Smicro, calculated using the t-plot method (Gregg and Sing 1982)], the pore volume (Vp, estimated at p/p0 ≈ 0.98), the volume of micropores (Vmicro) and the average pore radius (Rav, calculated for the model of cylindrical pores, Dp = 4Vpor/SBET) were determined. Pore volume distributions in the function of their sizes were calculated using the Barrett–Joyner–Halenda (BJH) method (Barret et al. 1951).

2.5 Determination of macropores volume

In order to determine the total pores and macropores volumes, the pores of these samples were filled with methanol. The samples were firstly dried at 110 for 24 h to eliminate the physically adsorbed water. Using a glass analytical burette (V = 1 cm3) small portions of methanol were added to the sample (known mass) and the pores filling process was ultrasound-aided. The pores filling was repeated until they were completely full. The titration procedures was repeated three times. After filling the pores, the volume of methanol consumed for making the pores full in a given weight of the tested material was read. The total pore volume was calculated according to Eq. 2:
$${{\text{V}}_{{\text{total*}}}}={{{{\text{V}}_{{\text{me,av}}}}} \mathord{\left/ {\vphantom {{{{\text{V}}_{{\text{me,av}}}}} {{{\text{m}}_{\text{s}}}}}} \right. \kern-0pt} {{{\text{m}}_{\text{s}}}}}$$
(2)
where Vtotal*—the total pores volume [cm3 g−1], Vme,av—the average volume of the methanol filling pores [cm3], ms—the sample mass [g].
The volume of macropores (Vmacro*) was determined from the Eq. 3:
$${{\text{V}}_{{\text{macro*}}}}={{\text{V}}_{{\text{total*}}}} - {{\text{V}}_{\text{p}}}$$
(3)

where Vtotal*—the total volume of pores [cm3 g−1], Vp—the volume of sorption pores obtained from the N2 adsorption/desorption data [cm3 g−1].

2.6 Spectroscopic characteristics

The Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS) was used to record the spectra (Bio-Rad Excalibur 3000MX spectrometer, detector MTEC 300). The spectra were recorded in the range 4000–400 cm−1.

2.7 Thermal analysis

The thermal studies of the samples were carried out heating in air atmosphere from 20 to 1200 °C (heating rate 10° min−1) using a Derivatograph C (Paulik, Paulik & Erdey, MOM, Budapest). The weight of the test samples was about 16 mg. The TG-DTG-DTA curves were registered. Ceramic crucibles and Al2O3 as a reference material were used in the investigations.

2.8 Photocatalytic test

The obtained materials were studied for their photocatalytic properties. Methylene blue (C16H18ClN3S, Co = 1 × 10−5 mol L−1) which is a standard dye commonly used in the photocatalytic studies was used. The tests were carried out in a glass reactor (UV-RS-2, Heraeus) under ultra violet radiation. The ratio of sample mass to the solution was 1 mg/1 ml. The reactor with the test sample was placed on a table with a magnetic stirrer in order to ensure the same distribution of the catalyst in the entire volume of the system. The solution was mixed with the test sample without access to light for 30 min to determine dye adsorption on the photocatalyst surface. Then the UV light was on. The samples were taken at regular intervals, filtered using syringe filters and centrifuged (2 × 15 min, 12,000 rpm). Using the UV/VIS spectrophotometer (Helios Gamma, Spectro-Lab, Poland) the solution concentrations were measured based on the calibration curve (y = 176.06x + 0.0664, R2 = 0.9983).

3 Results and discussion

3.1 Pressure and temperature changes obtained during MChT

Figure 1 presents an exemplary course of temperature (a) and pressure (b) changes recorded during the mechanochemical preparation of STC composites series. It can be clearly seen that at small rotation (300 rpm) the temperature and pressure values increase systematically in each subsequent cycle. The use of 500 and 700 rpm results in slightly different effects: although the temperature systematically increases after the maximum value in the first cycle the obtained pressures are reduced. This may indicate the highest efficiency of the first grinding cycle at such high rotation speed followed by gradual stabilization of the system. Analyzing the course of the curves in Fig. 1b, it can be seen that the highest pressure values were achieved for the sample subjected to a mechanochemical treatment at 700 rpm. However, with the increasing processing time, the temperature of all systems increases. The highest values of the temperature and pressure are obtained for the STC-700 sample (Fig. 1a). Similar courses of the temperature and pressure changes were obtained for all tested materials.

Fig. 1

Exemplary changes of temperature (a) and pressure (b) during the mechanochemical treatment of STC series composite

3.2 Porous structure

In Fig. 2 the low-temperature N2 adsorption/desorption isotherms (a, c, e, g) and dV/dR (b, d, f, h) curves for the prepared samples are presented. As follows from the analysis of the course of adsorption isotherms they are of type IV according to the IUPAC classification (Rouquerol et al. 1994). The isotherms characterized by poorly developed hysteresis loops (IV type) indicate that the obtained composites are mesoporous materials, in the pores of which the phenomenon of capillary condensation is observed. The course of the analyzed isotherms indicates also a small number of micropores.

Fig. 2

Low-temperature adsorption/desorption isotherms of nitrogen (a, c, e, g) and pore volume distribution functions dV/dR regarding their radius (b, d, f, g) for all samples

The analysis of the isotherms shape shows clearly that due to the mechanochemical treatment, the porous structure of all materials including SiO2 is destroyed (S, ST and STC series). This is the most evident during the mechanochemical treatment of initial SiO2 (Fig. 2a) and composites obtained on its base—the ST (Fig. 2e) and STC (Fig. 2g) series. As one can see the MChT at the rotation speed of 300 rpm causes partial lowering of the isotherms. However, the rotation speeds 500 and 700 rpm cause that the isotherms are placed horizontally just above the p/p0 axis. This suggests an intense reduction in the structural parameters and changes in the porosity. As follows after MChT the dV/dR curves for the samples containing SiO2 (S, ST and STC series) have monomodal character and are characterized by narrow mesopores at Rdom = 2 nm while the dV/dR band for SiO2 ini was relatively wide with a maximum at 3 nm. The mechanochemical modification caused the decrease of the pore volume but did not change the dominant pore size which is ~ 2 nm (Fig. 2b, f, h). These observations are confirmed by the structural parameters included in Table 1.

Table 1

Parameters of the porous structure of obtained materials

Sample

SBET (m2 g−1)

Smicro (m2 g−1)

Sext (m2 g−1)

Vp (cm3 g−1)

Vmicro (cm3 g−1)

Rav [nm]

Vtotal* (cm3 g−1)

Vmacro* (cm3 g−1)

ρ (g cm−3)

TiO2 ini

6.5

2.6

3.9

0.020

0.001

6.10

0.433

0.414

0.66

T-300

7.7

3.3

4.4

0.034

0.001

8.77

0.466

0.432

0.99

T-500

10.8

2.4

8.4

0.049

0.001

9.04

0.367

0.318

1.26

T-700

11.3

1.9

9.4

0.052

0.001

9.21

0.300

0.248

1.51

SiO2ini

350

37.7

312.3

1.520

0.013

8.66

2.083

0.563

0.12

S-300

236.1

23.5

212.6

0.430

0.008

3.66

1.033

0.603

0.23

S-500

38.1

7.3

30.8

0.122

0.003

6.45

0.483

0.361

0.42

S-700

27

4.7

22.3

0.098

0.002

7.31

0.466

0.368

0.41

ST-300

230.9

22.9

207.9

0.411

0.0081

3.56

1.333

0.922

0.21

ST-500

34.7

8.2

26.5

0.112

0.003

6.45

0.599

0.487

0.46

ST-700

26.6

8.2

18.5

0.085

0.003

6.37

0.483

0.398

0.40

STC-300

236.7

28.3

208.4

0.415

0.010

3.51

1.449

1.034

0.36

STC-500

41.9

9.7

32.3

0.121

0.004

5.76

0.616

0.495

0.36

STC-700

29.1

7.2

21.9

0.092

0.003

6.34

0.533

1.774

0.45

C

441.3

106.9

334.3

0.606

0.047

2.75

Smicro the specific surface of micropores, Sext the external surface, Vp the total volume of sorption pores, Vmicro the volume of micropores Vtotal* the total pores volume determined using methanol, Vmacro* the macropores volume determined using methanol

The TiO2 ini which had a poorly developed porous structure and the T-300, T-500, T-700 obtained a better developed porous structure than that of TiO2 ini after the mechanochemical treatment (Fig. 2c, d). However, in the case of SiO2 an opposite effect was observed. The isotherms are gradually placed higher relative to the p/p0 axis which indicates an increase in the porosity of the obtained materials after MChT. These materials (except for T-700) do not have clearly developed dominant pores (Fig. 2d). The bandwidth is wide and the average pore radius is almost 10 nm (Fig. 2d). Only the T-700 material is characterized by a clearly created peak with the maximum at ~ 2 nm indicating the dominant pore radius Rdom.

Table 1 presents the structural parameters of composites obtained in the mechanochemical treatment process. The SiO2 milling results in a significant reduction in the specific surface area (SBET) and the surface of micropores (Smicro) of the obtained materials. The initial silica has a well-developed surface area (350 m2 g−1), which after MChT decreases to 236.1 (S-300), 38.1 (S-500) and 27 (S-700) (Table 1). Similar changes are observed for the other parameters included in Table 1, except for bulk density (this parameter increases during the MChT process).

The analysis of the presented data shows that in a series of composites including SiO2 (ST and STC series) obtained by mechanochemical treatment, the highest specific surface area and pore volume are found in the composites obtained at lower revolutions (300 rpm) which is due to the behaviour of the main component, SiO2, whose structure is easily destroyed during the MChT process.

The addition of TiO2 into the structure (ST series) causes a small decrease of SBET which is not observed in the case of the Vp parameter. This results from the contribution of both SiO2 (main component, decreasing the porosity after MChT) and TiO2 (additive, increasing this parameter after MChT) in the composite structure. The similar dependences are observed for the STC series but the SBET parameters are slightly larger than for the ST series which is a result of the addition of carbon black of a relatively large specific surface area (441.3 m2 g−1). For the last two series changes of the other parameter are similar to those for SiO2 because of much higher content of SiO2 in them.

Analyzing the data on the initial TiO2, it can be concluded that the material has a poorly developed specific surface area (6.5 m2 g−1) where almost half (2.6 m2 g−1) is the micropore surface. The mechanochemical treatment of this material increases the specific surface area (SBET) of subsequent composites, however, it is not a significant increase (T-700, SBET = 11.3 m2 g−1). The observed surface increase in the case of TiO2 results from the considerable fragmentation of the material. The increase in the specific surface area of these samples can be clearly seen also in the SEM images (Fig. 3). TiO2 after the mechanochemical treatment at 700 rpm has clearly sharped edges (Fig. 3b) while the grain edges of T-300 are smooth (Fig. 3a).

Fig. 3

SEM pictures TiO2 after MChT at 300 (a) and 700 (b) rpm for 1 h

Figure 4 shows the course of changes in the average total pore volume and that of macropores for all mechanochemically modified materials. These data were obtained on the basis of filling the material pores with methanol. As follows from the course of the curves, the mechanochemical treatment causes the reduction of the studied parameters. The tendency is the same for all samples. With the increase mill rotation speed, the total pore volume Vtotal and the volume of macropores Vmacro decrease (Fig. 4).

Fig. 4

Exemplary changes in the total pore volume and that of macropores depending on the speed of mill rotation

3.3 FT-IR/PAS analysis

In order to have a better insight into the structure of synthesized materials, infrared spectroscopy was used (FT-IR, Fourier transform infrared spectroscopy) and more precisely, photoacoustic spectroscopy (FT-IR/PAS, Fourier transform infrared photoacoustic spectroscopy). This technique has huge advantages over the commonly used transmission technique because it does not require prior sample preparation and is non-destructive. In Fig. 5a TiO2 framework vibrations (below 2000 cm−1) and hydroxyl groups bands (3745, 3670 cm−1—isolated –OH and hydrogen bonded –OH⋯H, respectively) are visible. There are no spectacular changes in the spectra of TiO2 series samples compared to the initial TiO2 material. The only difference is noted in the –OH stretching range (increase in intensity of the wide band with the maximum at 3390 cm−1). This band shows the presence of both –OH and hydrogen bonded –OH⋯H in the Ti–OH structures and/or physically adsorbed water.

Fig. 5

FT-IR/PAS spectra of T-300, T-500, T-700 and initial TiO2 samples (a) and S-300, S-500, S-700 and initial SiO2 samples (b) in 4000–400 cm−1 range

Figure 5b presents the spectra of SiO2 samples. The peak at approx. 3740 cm−1, visible in all spectra is assigned to the isolated silanol groups ≡SiOH. The peak at ~ 3622 cm−1 is responsible for the presence of hydrogen bonded SiOH⋯OSi groups, and more accurately it indicates the presence of internal hydroxyl groups. The wide band with the maximum at ~ 3400 cm  shows the presence of both –OH and hydrogen bonded –OH⋯H in the Si–OH structures and physically adsorbed water. The broad, intense bands in the range of 1300–1000 cm−1 can be attributed to the asymmetric stretching vibrations of Si–O–Si bridges, and the peaks at ~ 795 cm−1 and ~ 470 cm−1 can be assigned to the symmetric stretching and deformation modes of Si–O–Si, respectively. The IR bands observed within 980–910 cm−1 can be assigned to the Si–O–Si stretching vibrations. The band at 972 cm−1 is visible only in the spectrum of the initial silica, but not in the SiO2 series samples spectra, which may indicate that the rotation and energy produced during this process affect the change of silica structure—the band at 972 cm−1 shifts to a lower wavenumber (937 cm−1) for the SiO2 samples.

As you can see the use of high rotation speed (S-500 and S-700 samples) causes a reduction in the quantity of isolated silanol groups (3734 cm−1) while the quantity of hydrogen bonded SiOH⋯OSi groups remains practically unchanged (3622 cm−1).

In this case there can be also observed the difference in the amount of isolated silanol groups ≡SiOH—the intensity of the peaks is lower in the case of ST-500 and ST-700 samples (Fig. 6a). The investigations indicate that there can be a relationship between the intensity of the band at ~ 940 cm−1 and that at ~ 800 cm−1 (which is responsible for the symmetric Si-O-Si symmetric vibrations). The intensity ratio of 940/800 cm−1 is much higher for the silica materials with other ions incorporated into the silica structure. Thus an increase in 940 cm−1 band intensity relative to the band at 800 cm−1 may be evidence of attachment of titania ions into the crystal lattice of silica. In our case, the higher the rotation speed, the higher the 940/800 cm−1 ratio. This may show the incorporation of titanium into the silica structure.

Fig. 6

FT-IR/PAS spectra of ST-300, ST-500, ST-700 and initial SiO2 and TiO2 samples (a) and STC-300, STC-500, STC-700 and initial SiO2 and TiO2 samples (b) in the 4000–400 cm−1 range

In the case of the samples with carbon addition (STC series), the spectra are similar to the previous ones (ST series), but all peaks in the spectra of STC series are of much lower intensity (Fig. 6b). This is probably due to the addition of carbon, which somehow “seals” signals from silica. Similarly to the ST series, the higher the rotation speed, the higher the ~ 940/800 cm−1 ratio—it may be evidence of titanium incorporation into the silica structure.

3.4 Thermal analysis

Application of thermal analysis made it possible to estimate thermal stability of the studied materials. Three series of samples under investigations are individual inorganic oxides (S and T series) or composites (ST series). The initial materials (SiO2 and TiO2) are thermally stable. The mass changes during the thermal analysis are a results of desorption of physically bound water (20–200 °C) and surface hydroxyls as well as intraglobular water (above 200 °C). The presence of such forms of water was proved by the FTIR investigations. The fourth series contains additionally carbon matter (carbon black, 1%) but its content is very small and significant effects resulting from its presence are not noticeable. Figure 7 presents the exemplary results of thermal analysis of ST series composites. The course of the TG curves (Fig. 7a) appears to be dominated by the main component of the composite—SiO2. The intensive mass loss is observed in the temperature range 20–200 °C (~ 4–7%). At a temperature higher than 200 °C the successive mass loss seems to be dependent on the rotation speed: the higher rotation speed, the grater mass loss. These observations indicate that MChT introduces larger amounts of hydroxyl groups into the composite structure. This is confirmed by the courses of DTG (Fig. 7b) and DTA (Fig. 7c) curves.

Fig. 7

The course of the TG (a), DTG (b) and DTA (c) curves obtained for the ST composites series

3.5 Photocatalytic characteristics

For all series of materials including TiO2 (T, ST and STC series) the photocatalytic investigations were carried out. During the measurements the initial adsorption of the dye on the catalyst was observed within the first 30 min. In the case of TiO2 series the adsorption values were 4–21%. For the SiO2 based materials (ST and STC) the adsorption was higher due to silica contribution to the composite structure (Fig. 8a, b). Generally, the increase of the rotation speed causes the decrease of structural parameters, which limits the adsorption, but the addition of carbon black causes higher adsorption for the STC series (Fig. 8b), than for the ST series (Fig. 8a). The exemplary adsorption values are 9.5% for ST-700 (Fig. 8a) and 25% for STC-700 (Fig. 8b).

Fig. 8

Adsorption and degradation steps of methylene blue using ST (a) and STC (b) where Co is the initial concentration of MB after adsorption

The investigation results show that the mechanochemical treatment worsens dye degradation efficiency (Fig. 9a, b). The course of the curves in Fig. 9a shows that the increase in the rotation speed reduces effectiveness of TiO2 as a photocatalyst in the range of UV radiation in the case of all series. Total degradation of the dye was observed after about 20 min. However, the attention should be paid to comparable degradation processes using pure TiO2 (Fig. 9a) and composite materials with a much lower content of this photocatalyst (only 5%, Fig. 9b).

Fig. 9

Decomposition rate of methylene blue using TiO2 (a) and ST (b)

4 Conclusions

We have investigated structural, thermal, and photocatalytic properties of composite materials containing SiO2, TiO2 and carbon black as a carbon source. The influence of the speed of mechanochemical treatment on these parameters was analyzed. It was shown that mechanochemical treatment allows preparation of composite materials with new structural properties. Increasing the rotation speed reduces the specific surface area (SBET) and the pore volume (Vp) of S, ST and STC series of composite materials. Only in the case of TiO2 the specific surface area increased slightly. The increase in the rotation speed during the mechanochemical treatment resulted in the increasing bulk density of the tested samples. Thermal analysis showed significant thermal stability of the obtained materials. Up to 200 °C desorption of physically bound water took place whereas the release of surface hydroxyl groups and intraglobular water, especially from the surface of SiO2-based materials, was observed at a higher temperature. The photocatalytic tests results indicate that the mechanochemical treatment does not improve photocatalytic activity of the studied materials in relation to methylene blue in the UV range.

Notes

References

  1. Anastas, P.T., Kirchhoff, M.M.: Origins, current status, and future challenges of green chemistry. ACC Chem. Res. 35(9), 686–694 (2002).  https://doi.org/10.1021/ar010065m CrossRefGoogle Scholar
  2. Anderson, C., Bard, A.J.: Improved photocatalytic activity and characterization of mixed TiO2/SiO2 and TiO2/Al2O3 materials. J. Phys. Chem. B. 101(14), 2611–2616 (1997).  https://doi.org/10.1021/jp9626982 CrossRefGoogle Scholar
  3. Barret, E.P., Joyner, L.G., Halenda, P.P.: The determination of pore volumes and area distributions in porous substances. J. Am. Chem. Soc. 73(1), 373–380 (1951)CrossRefGoogle Scholar
  4. Carneiro, J.O., Azevedo, S., Fernandes, F., Freitas, E., Pereira, M., Tavares, C.J., Lanceros-Méndez, S., Teixeira, V.: Synthesis of iron-doped TiO2 nanoparticles by ball-milling process: the influence of process parameters on the structural, optical, magnetic, and photocatalytic properties. J. Mater. Sci. 49(21), 7476–7488 (2014)CrossRefGoogle Scholar
  5. Chong, M.N., Jin, B., Chow, C.W., Saint, C.: Recent developments in photocatalytic water treatment technology: a review. Water Res. 44(10), 2997–3027 (2010)CrossRefGoogle Scholar
  6. Fu, X., Clark, L.A., Yang, Q., Anderson, M.A.: Enhanced photocatalytic performance of titania-based binary metal oxides: TiO2/SiO2 and TiO2/ZrO2. Environ. Sci. Technol. 30(2), 647–653 (1996).  https://doi.org/10.1021/es950391v CrossRefGoogle Scholar
  7. Fu, H., Zhang, L., Yao, W., Zhu, Y.: Photocatalytic properties of nanosized Bi2WO6 catalysts synthesized via a hydrothermal process. Appl. Catal., B. 66(1–2), 100–110 (2006).  https://doi.org/10.1016/j.apcatb.2006.02.022 CrossRefGoogle Scholar
  8. Gao, B., Chen, G.Z., Puma, G.L.: Carbon nanotubes/titanium dioxide (CNTs/TiO2) nanocomposites prepared by conventional and novel surfactant wrapping sol–gel methods exhibiting enhanced photocatalytic activity. Appl. Catal., B. 89, 503–509 (2009).  https://doi.org/10.1016/j.apcatb.2009.01.009 CrossRefGoogle Scholar
  9. Ghorai, T.K., Chakraborty, M., Pramanik, P.: Photocatalytic performance of nano-photocatalyst from TiO2 and Fe2O3 by mechanochemical synthesis. J. Alloys Compd. 509(32), 8158–8164 (2011).  https://doi.org/10.1016/j.jallcom.2011.05.069 CrossRefGoogle Scholar
  10. Gregg, S.J., Sing, K.S.W.: Adsorption, Surface Area and Porosity, 2nd edn. Academic Press, London (1982)Google Scholar
  11. Hanaor, D.A., Sorrell, C.C.: Review of the anatase to rutile phase transformation. J. Mater. Sci. 46(4), 855–874 (2011)CrossRefGoogle Scholar
  12. Haque, E., Jun, J.W., Jhung, S.H.: Adsorptive removal of methyl orange and methylene blue from aqueous solution with a metal-organic framework material, iron terephthalate (MOF-235). J. Hazard. Mater. 185(1), 507–511 (2011).  https://doi.org/10.1016/j.jhazmat.2010.09.035 CrossRefGoogle Scholar
  13. Herrmann, J.M.: Heterogeneous photocatalysis: fundamentals and applications to the removal of various types of aqueous pollutants. Catal. Today. 53(1), 115–129 (1999).  https://doi.org/10.1016/S0920-5861(99)00107-8 CrossRefGoogle Scholar
  14. Jalalah, M., Faisal, M., Bouzid, H., Ismail, A.A., Al-Sayari, S.A.: Dielectric and photocatalytic properties of sulfur doped TiO2 nanoparticles prepared by ball milling. Mater. Res. Bull. 48(9), 3351–3356 (2013).  https://doi.org/10.1016/j.materresbull.2013.05.023 CrossRefGoogle Scholar
  15. Kim, S.Y., Lim, T.H., Chang, T.S., Shin, C.H.: Photocatalysis of methylene blue on titanium dioxide nanoparticles synthesized by modified sol-hydrothermal process of TiCl4. Catal. Lett. 117(3–4), 112–118 (2007)CrossRefGoogle Scholar
  16. Kucio, K., Charmas, B.: Mechanochemia - metoda syntezy i aktywacji fotokatalizatorów na bazie TiO2. In: M. Drach (eds.) Nowe trendy w fizykochemicznych badaniach granic faz, in polish, pp. 167–179. Polish Chemical Society, Warszawa (2018). ISBN 978-83-60988-25-2Google Scholar
  17. Li, W.-W., Yu, H.-Q., He, Z.: Towards sustainable wastewater treatment by using microbial fuel cells-centered technologies. Energy Environ. Sci. 7(3), 911–924 (2014).  https://doi.org/10.1039/C3EE43106A CrossRefGoogle Scholar
  18. Martinez-de La Cruz, A., Garcia Perez, U.G.: Photocatalytic properties of BiVO4 prepared by the co-precipitation method: degradation of rhodamine B and possible reaction mechanisms under visible irradiation. Mater. Res. Bull. 45(2), 135–141 (2010).  https://doi.org/10.1016/j.materresbull.2009.09.029 CrossRefGoogle Scholar
  19. Mills, A., Le Hunte, S.: An overview of semiconductor photocatalysis. J. Photochem. Photobiol. A. 108(1), 1–35 (1997).  https://doi.org/10.1016/S1010-6030(97)00118-4 CrossRefGoogle Scholar
  20. Molchanov, V.V., Buyanov, R.A.: Scientific grounds for the application of mechanochemistry to catalyst preparation. Kinet. Catal. 42(3), 366–374 (2001)CrossRefGoogle Scholar
  21. Nakata, K., Fujishima, A.: TiO2 photocatalysis: design and applications. J. Photochem. Photobiol. C. 13(3), 169–189 (2012).  https://doi.org/10.1016/j.jphotochemrev.2012.06.001 CrossRefGoogle Scholar
  22. O’Neill, C., Hawkes, F.R., Hawkes, D.L., Lourenço, N.D., Pinheiro, H.M., Delée, W.: Colour in textile effluents–sources, measurement, discharge consents and simulation: a review. J. Chem. Technol. Biotechnol. 74(11), 1009–1018(1999).  https://doi.org/10.1002/(SICI)1097-4660(199911)74:11%3C1009::AID-JCTB153%3E3.0.CO;2-N CrossRefGoogle Scholar
  23. Pirkanniemi, K., Sillanpää, M.: Heterogeneous water phase catalysis as an environmental application: a review. Chemosphere. 48(10), 1047–1060 (2002).  https://doi.org/10.1016/S0045-6535(02)00168-6 CrossRefGoogle Scholar
  24. Rajeshwar, K., Osugi, M.E., Chanmanee, W., Chenthamarakshan, C.R., Zanoni, M.V.B., Kajitvichyanukul, P., Krishnan-Ayer, R.: Heterogeneous photocatalytic treatment of organic dyes in air and aqueous media. J. Photochem. Photobiol. C. 9(4), 171–192 (2008).  https://doi.org/10.1016/j.jphotochemrev.2008.09.001 CrossRefGoogle Scholar
  25. Rouquerol, J., Baron, G., Denoyel, R., Giesche, H., Groen, J., Klobes, P., Levitz, P., Neimark, A.V., Rigby, S., Skudas, R., Sing, K., Thommes, M., Unger, K.: Recommendations for the characterization of porous solids. Pure Appl. Chem. 66, 1739–1758 (1994)CrossRefGoogle Scholar
  26. Van Gerven, T., Mul, G., Moulijn, J., Stankiewicz, A.: A review of intensification of photocatalytic processes. Chem. Eng. Process. 46(9), 781–789 (2007).  https://doi.org/10.1016/j.cep.2007.05.012 CrossRefGoogle Scholar
  27. Wu, J.C.-S., Chen, C.H.: A visible-light response vanadium-doped titania nanocatalyst by sol–gel method. J. Photochem. Photobiol., A. 163(3), 509–515 (2004).  https://doi.org/10.1016/j.jphotochem.2004.02.007 CrossRefGoogle Scholar
  28. Wu, Z., Yuan, X., Zhang, J., Wang, H., Jiang, L., Zeng, G.: Photocatalytic decontamination of wastewater containing organic dyes by metal–organic frameworks and their derivatives. ChemCatChem. 9(1), 41–64 (2017).  https://doi.org/10.1002/cctc.201600808 CrossRefGoogle Scholar
  29. Yin, S., Yamaki, H., Komatsu, M., Zhang, Q., Wang, J., Tang, Q., Saito, F., Sato, T.: Preparation of nitrogen-doped titania with high visible light induced photocatalytic activity by mechanochemical reaction of titania and hexamethylenetetramine. J. Mater. Chem. 13(12), 2996–3001 (2003).  https://doi.org/10.1039/B309217H CrossRefGoogle Scholar
  30. Yu, J., Kudo, A.: Effects of structural variation on the photocatalytic performance of hydrothermally synthesized BiVO4. Adv. Funct. Mater. 16, 2163–2169 (2006).  https://doi.org/10.1002/adfm.200500799 CrossRefGoogle Scholar
  31. Yu, J., Zhao, X., Zhao, Q.: Effect of surface structure on photocatalytic activity of TiO2 thin films prepared by sol-gel method. Thin Solid Films. 379(1–2), 7–14 (2000).  https://doi.org/10.1016/S0040-6090(00)01542-X CrossRefGoogle Scholar
  32. Yu, J., Zhang, Y., Kudo, A.: Synthesis and photocatalytic performances of BiVO4 by ammonia co-precipitation process. J. Solid State Chem. 182(2), 223–228 (2009).  https://doi.org/10.1016/j.jssc.2008.10.021 CrossRefGoogle Scholar
  33. Zhang, H., Banfield, J.F.: Understanding polymorphic phase transformation behavior during growth of nanocrystalline aggregates: insights from TiO2. J. Phys. Chem. B. 104(15), 3481–3487 (2000).  https://doi.org/10.1021/jp000499j CrossRefGoogle Scholar
  34. Zhang, K., Guo, L.: Metal sulphide semiconductors for photocatalytic hydrogen production. Catal. Sci. Technol. 3(7), 1672–1690 (2013).  https://doi.org/10.1039/C3CY00018D CrossRefGoogle Scholar
  35. Zhang, F., Zhao, J., Zang, L., Shen, T., Hidaka, H., Pelizzetti, E., Serpone, N.: Photoassisted degradation of dye pollutants in aqueous TiO2 dispersions under irradiation by visible light. J. Mol. Catal. A: Chem. 120(1–2), 173–178 (1997).  https://doi.org/10.1016/S1381-1169(96)00405-0 CrossRefGoogle Scholar
  36. Zhang, M., Sheng, G., Fu, J., An, T., Wang, X., Hu, X.: Novel preparation of nanosized ZnO–SnO2 with high photocatalytic activity by homogeneous co-precipitation method. Mater. Lett. 59(28), 3641–3644 (2005).  https://doi.org/10.1016/j.matlet.2005.06.037 CrossRefGoogle Scholar
  37. Zhao, L., Chen, X., Wang, X., Zhang, Y., Wei, W., Sun, Y., Antonietti, M., Titirici, M.M.: One-step solvothermal synthesis of a carbon@ TiO2 dyade structure effectively promoting visible-light photocatalysis. Adv. Mater. 22(30), 3317–3321 (2010).  https://doi.org/10.1002/adma.201000660 CrossRefGoogle Scholar

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Authors and Affiliations

  1. 1.Department of Chromatographic Methods, Faculty of ChemistryMaria Curie-Skłodowska UniversityLublinPoland

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