Abstract
In this paper, we discuss the previous advances, current challenges, and future opportunities for the research of catalytic reduction of water pollutants. We present five case studies on the development of palladium-based catalysts for nitrate, chlorate, and perchlorate reduction with hydrogen gas under ambient conditions. We emphasize the realization of new functionalities through the screening and design of catalytic metal sites, including (i) platinum group metal (PGM) nanoparticles, (ii) the secondary metals for improving the reaction rate and product selectivity of nitrate reduction, (iii) oxygen-atom-transfer metal oxides for chlorate and perchlorate reduction, and (iv) ligand-enhanced coordination complexes for substantial activity enhancement. We also highlight the facile catalyst preparation approach that brought significant convenience to catalyst optimization. Based on our own studies, we then discuss directions of the catalyst research effort that are not immediately necessary or desirable, including (1) systematic study on the downstream aspects of under-developed catalysts, (2) random integration with hot concepts without a clear rationale, and (3) excessive and decorative experiments. We further address some general concerns regarding using H2 and PGMs in the catalytic system. Finally, we recommend future catalyst development in both “fundamental” and “applied” aspects. The purpose of this perspective is to remove major misconceptions about reductive catalysis research and bring back significant innovations for both scientific advancements and engineering applications to benefit environmental protection.
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References
Abu-Omar M M, Espenson J H (1995). Facile abstraction of successive oxygen atoms from perchlorate ions by methylrhenium dioxide. Inorganic Chemistry, 34(25): 6239–6240
Abu-Omar M M, McPherson L D, Arias J, Béreau V M (2000). Clean and efficient catalytic reduction of perchlorate. Angewandte Chemie International Edition in English, 39(23): 4310–4313
Barder T E, Buchwald S L (2007a). Insights into amine binding to biaryl phosphine palladium oxidative addition complexes and reductive elimination from biaryl phosphine arylpalladium amido complexes via density functional theory. Journal of the American Chemical Society, 129(39): 12003–12010
Barder T E, Buchwald S L (2007b). Rationale behind the resistance of dialkylbiaryl phosphines toward oxidation by molecular oxygen. Journal of the American Chemical Society, 129(16): 5096–5101
Baumgartner R, McNeill K (2012). Hydrodefluorination and hydrogenation of fluorobenzene under mild aqueous conditions. Environmental Science & Technology, 46(18): 10199–10205
Baumgartner R, Stieger G K, McNeill K (2013). Complete hydrodehalogenation of polyfluorinated and other polyhalogenated benzenes under mild catalytic conditions. Environmental Science & Technology, 47(12): 6545–6553
Becker A, Koch V, Sell M, Schindler H, Neuenfeldt G (1998). Method of removing chlorate and bromate compounds from water by catalytic reduction. European Patent EP0779880B1
Cerrillo J L, Lopes C W, Rey F, Palomares A E (2021). The Influence of the support nature and the metal precursor in the activity of Pd-based catalysts for the bromate reduction reaction. ChemCatChem, 13(4): 1230–1238
Chaplin B P, Reinhard M, Schneider W F, Schüth C, Shapley J R, Strathmann T J, Werth C J (2012). Critical review of Pd-based catalytic treatment of priority contaminants in water. Environmental Science & Technology, 46(7): 3655–3670
Chen C, Li K, Li C, Sun T, Jia J (2019). Combination of Pd−Cu catalysis and electrolytic H2 evolution for selective nitrate reduction using protonated polypyrrole as a cathode. Environmental Science & Technology, 53(23): 13868–13877
Chen F Y, Wu Z Y, Gupta S, Rivera D J, Lambeets S V, Pecaut S, Kim J Y T, Zhu P, Finfrock Y Z, Meira D M, et al. (2022). Efficient conversion of low-concentration nitrate sources into ammonia on a Ru-dispersed Cu nanowire electrocatalyst. Nature Nanotechnology, 17(7): 759–767
Chen G F, Yuan Y, Jiang H, Ren S Y, Ding L X, Ma L, Wu T, Lu J, Wang H (2020). Electrochemical reduction of nitrate to ammonia via direct eight-electron transfer using a copper-molecular solid catalyst. Nature Energy, 5(8): 605–613
Chen H, Xu Z, Wan H, Zheng J, Yin D, Zheng S (2010). Aqueous bromate reduction by catalytic hydrogenation over Pd/Al2O3 catalysts. Applied Catalysis B: Environmental, 96(3–4): 307–313
Chen X, Huo X, Liu J, Wang Y, Werth C J, Strathmann T J (2017). Exploring beyond palladium: catalytic reduction of aqueous oxyanion pollutants with alternative platinum group metals and new mechanistic implications. Chemical Engineering Journal, 313: 745–752
Choe J K, Boyanov M I, Liu J, Kemner K M, Werth C J, Strathmann T J (2014). X-ray spectroscopic characterization of immobilized rhenium species in hydrated rhenium-palladium bimetallic catalysts used for perchlorate water treatment. Journal of Physical Chemistry C, 118(22): 11666–11676
Choe J K, Shapley J R, Strathmann T J, Werth C J (2010). Influence of rhenium speciation on the stability and activity of Re/Pd bimetal catalysts used for perchlorate reduction. Environmental Science & Technology, 44(12): 4716–4721
Chu C, Huang D, Gupta S, Weon S, Niu J, Stavitski E, Muhich C, Kim J H (2021). Neighboring Pd single atoms surpass isolated single atoms for selective hydrodehalogenation catalysis. Nature Communications, 12(1): 5179
Chung J, Nerenberg R, Rittmann B E (2007). Evaluation for biological reduction of nitrate and perchlorate in brine water using the hydrogen-based membrane biofilm reactor. Journal of Environmental Engineering, 133(2): 157–164
Clem R G, Huffman E (1968). Amperometric titration of palladium(II) by oxidation with hypochlorite. Analytical Chemistry, 40(6): 945–948
Crowell W R, Yost D M, Roberts J D (1940). The catalytic effect of osmium compounds on the reduction of perchloric acid by hydrobromic acid. Journal of the American Chemical Society, 62(8): 2176–2178
Durkin D P, Ye T, Choi J, Livi K J, Long H C D, Trulove P C, Fairbrother D H, Haverhals L M, Shuai D (2018). Sustainable and scalable natural fiber welded palladium-indium catalysts for nitrate reduction. Applied Catalysis B: Environmental, 221: 290–301
Fontana D, Pietrantonio M, Pucciarmati S, Torelli G N, Bonomi C, Masi F (2018). Palladium recovery from monolithic ceramic capacitors by leaching, solvent extraction and reduction. Journal of Material Cycles and Waste Management, 20(2): 1199–1206
Fotouhi-Far F, Bashiri H, Hamadanian M, Keshavarz M H (2021). A new approach for the leaching of palladium from spent Pd/C catalyst in HCl−H2O2 system. Protection of Metals and Physical Chemistry of Surfaces, 57(2): 297–305
Gao J, Ren C, Huo X, Ji R, Wen X, Guo J, Liu J (2021). Supported palladium catalysts: a facile preparation method and implications to reductive catalysis technology for water treatment. ACS ES&T Engineering, 1(3): 562–570
Grittini C, Malcomson M, Fernando Q, Korte N (1995). Rapid dechlorination of polychlorinated biphenyls on the surface of a Pd/Fe bimetallic system. Environmental Science & Technology, 29(11): 2898–2900
Gu B, Brown G M, Chiang C C (2007). Treatment of perchlorate-contaminated groundwater using highly selective, regenerable ion-exchange technologies. Environmental Science & Technology, 41(17): 6277–6282
Guo S, Heck K, Kasiraju S, Qian H, Zhao Z, Grabow L C, Miller J T, Wong M S (2018). Insights into nitrate reduction over indium-decorated palladium nanoparticle catalysts. ACS Catalysis, 8(1): 503–515
Guo S, Li H, Heck K N, Luan X, Guo W, Henkelman G, Wong M S (2022). Gold boosts nitrate reduction and deactivation resistance to indium-promoted palladium catalysts. Applied Catalysis B: Environmental, 305: 121048
Haight GJr (1954). Mechanism of the tungstate catalyzed reduction of perchlorate by stannous chloride. Journal of the American Chemical Society, 76(18): 4718–4721
Haight GJr, Sager W (1952). Evidence for preferential one-step divalent changes in the molybdate-catalyzed reduction of perchlorate by stannous ion in sulfuric acid solution. Journal of the American Chemical Society, 74(23): 6056–6059
Hamid S, Bae S, Lee W (2018). Novel bimetallic catalyst supported by red mud for enhanced nitrate reduction. Chemical Engineering Journal, 348: 877–887
He W, Zhang J, Dieckhöfer S, Varhade S, Brix A C, Lielpetere A, Seisel S, Junqueira J R C, Schuhmann W (2022). Splicing the active phases of copper/cobalt-based catalysts achieves high-rate tandem electroreduction of nitrate to ammonia. Nature Communications, 13(1): 1129
Heck K N, Garcia-Segura S, Westerhoff P, Wong M S (2019). Catalytic converters for water treatment. Accounts of Chemical Research, 52(4): 906–915
Holm R H (1987). Metal-centered oxygen atom transfer reactions. Chemical Reviews, 87(6): 1401–1449
Hörold S, Vorlop K D, Tacke T, Sell M (1993). Development of catalysts for a selective nitrate and nitrite removal from drinking water. Catalysis Today, 17(1–2): 21–30
Howe J L, Mercer F N (1925). Contributions to the study of ruthenium IX. Solubility of ruthenium in hypochlorite solutions and an attempt to utilize the reaction for the quantitative determination of the metal. Journal of the American Chemical Society, 47(12): 2926–2932
Huo X, Van Hoomissen D J, Liu J, Vyas S, Strathmann T J (2017). Hydrogenation of aqueous nitrate and nitrite with ruthenium catalysts. Applied Catalysis B: Environmental, 211: 188–198
Hurley K D, Shapley J R (2007). Efficient heterogeneous catalytic reduction of perchlorate in water. Environmental Science & Technology, 41(6): 2044–2049
Hurley K D, Zhang Y, Shapley J R (2009). Ligand-enhanced reduction of perchlorate in water with heterogeneous Re−Pd/C catalysts. Journal of the American Chemical Society, 131(40): 14172–14173
Kolthoff I (1921). Jodometrische studien. Fresenius’ Zeitschrift für Analytische Chemie, 60(12): 448–457
Kong X, Xiao J, Chen A, Chen L, Li C, Feng L, Ren X, Fan X, Sun W, Sun Z (2022). Enhanced catalytic denitrification performance of ruthenium-based catalysts by hydrogen spillover from a palladium promoter. Journal of Colloid and Interface Science, 608(Pt 3): 2973–2984
Kuznetsova L I, Kuznetsova N I, Koscheev S V, Zaikovskii V I, Lisitsyn A S, Kaprielova K M, Kirillova N V, Twardowski Z (2012). Carbon-supported iridium catalyst for reduction of chlorate ions with hydrogen in concentrated solutions of sodium chloride. Applied Catalysis A, General, 427–428: 8–15
Lai C Y, Wu M, Lu X, Wang Y, Yuan Z, Guo J (2021). Microbial perchlorate reduction driven by ethane and propane. Environmental Science & Technology, 55(3): 2006–2015
Li J, Li M, An N, Zhang S, Song Q, Yang Y, Li J, Liu X (2022). Boosted ammonium production by single cobalt atom catalysts with high Faradic efficiencies. Proceedings of the National Academy of Sciences of the United States of America, 119(29): e2123450119
Li J, Zhan G, Yang J, Quan F, Mao C, Liu Y, Wang B, Lei F, Li L, Chan A W M, Xu L, Shi Y, Du Y, Hao W, Wong P K, Wang J, Dou S X, Zhang L, Yu J C (2020). Efficient ammonia electrosynthesis from nitrate on strained ruthenium nanoclusters. Journal of the American Chemical Society, 142(15): 7036–7046
Lim J, Liu C Y, Park J, Liu Y H, Senftle T P, Lee S W, Hatzell M C (2021). Structure sensitivity of Pd facets for enhanced electrochemical nitrate reduction to ammonia. ACS Catalysis, 11(12): 7568–7577
Liu J, Chen X, Wang Y, Strathmann T J, Werth C J (2015a). Mechanism and mitigation of the decomposition of an oxorhenium complex-based heterogeneous catalyst for perchlorate reduction in water. Environmental Science & Technology, 49(21): 12932–12940
Liu J, Choe J K, Sasnow Z, Werth C J, Strathmann T J (2013). Application of a Re-Pd bimetallic catalyst for treatment of perchlorate in waste ion-exchange regenerant brine. Water Research, 47(1): 91–101
Liu J, Choe J K, Wang Y, Shapley J R, Werth C J, Strathmann T J (2015b). Bioinspired complex-nanoparticle hybrid catalyst system for aqueous perchlorate reduction: Rhenium speciation and its influence on catalyst activity. ACS Catalysis, 5(2): 511–522
Liu J, Han M, Wu D, Chen X, Choe J K, Werth C J, Strathmann T J (2016a). A new bioinspired perchlorate reduction catalyst with significantly enhanced stability via rational tuning of rhenium coordination chemistry and heterogeneous reaction pathway. Environmental Science & Technology, 50(11): 5874–5881
Liu J, Su X, Han M, Wu D, Gray D L, Shapley J R, Werth C J, Strathmann T J (2017). Ligand design for isomer-selective oxorhenium(V) complex synthesis. Inorganic Chemistry, 56(3): 1757–1769
Liu J, Wu D, Su X, Han M, Kimura S Y, Gray D L, Shapley J R, Abu-Omar M M, Werth C J, Strathmann T J (2016b). Configuration control in the synthesis of homo-and heteroleptic bis (oxazolinylphenolato/thiazolinylphenolato) chelate ligand complexes of oxorhenium(V): isomer effect on ancillary ligand exchange dynamics and implications for perchlorate reduction catalysis. Inorganic Chemistry, 55(5): 2597–2611
Lowry G V, Reinhard M (2000). Pd-catalyzed TCE dechlorination in groundwater: solute effects, biological control, and oxidative catalyst regeneration. Environmental Science & Technology, 34(15): 3217–3223
Lowry G V, Reinhard M (2001). Pd-catalyzed TCE dechlorination in water: effect of [H2](aq) and H2-utilizing competitive solutes on the TCE dechlorination rate and product distribution. Environmental Science & Technology, 35(4): 696–702
Mazin I (2022). Inverse Occam’s razor. Nature Physics, 18(4): 367–368
Nature Nanotechnology Editorial Board (2022). Bringing out the Occam’s razor in peer-review. Nature Nanotechnology, 17(6): 561
Nogueira C A, Paiva A P, Costa M C, Rosa da Costa A M (2020). Leaching efficiency and kinetics of the recovery of palladium and rhodium from a spent auto-catalyst in HCl/CuCl2 media. Environmental Technology, 41(18): 2293–2304
Park J, An S, Jho E H, Bae S, Choi Y, Choe J K (2020). Exploring reductive degradation of fluorinated pharmaceuticals using Al2O3-supported Pt-group metallic catalysts: catalytic reactivity, reaction pathways, and toxicity assessment. Water Research, 185: 116242
Park J, Hwang Y, Bae S (2019). Nitrate reduction on surface of Pd/Sn catalysts supported by coal fly ash-derived zeolites. Journal of Hazardous Materials, 374: 309–318
Prüsse U, Hähnlein M, Daum J, Vorlop K D (2000). Improving the catalytic nitrate reduction. Catalysis Today, 55(1–2): 79–90
Prüsse U, Hörold S, Vorlop K D (1997). Einfluß der präparationsbedingungen auf die eigenschaften von bimetallkatalysatoren zur nitratentfernung aus wasser. Chemieingenieurtechnik (Weinheim), 69(1–2): 93–97
Prüsse U, Vorlop K D (2001). Supported bimetallic palladium catalysts for water-phase nitrate reduction. Journal of Molecular Catalysis A Chemical, 173(1–2): 313–328
Ren C, Bi E Y, Gao J, Liu J (2022). Molybdenum-catalyzed perchlorate reduction: robustness, challenges, and solutions. ACS ES&T Engineering, 2(2): 181–188
Ren C, Liu J (2021). Bioinspired catalytic reduction of aqueous perchlorate by one single-metal site with high stability against oxidative deactivation. ACS Catalysis, 11(11): 6715–6725
Ren C, Yang P, Gao J, Huo X, Min X, Bi E Y, Liu Y, Wang Y, Zhu M, Liu J (2020). Catalytic reduction of aqueous chlorate with MoOx immobilized on Pd/C. ACS Catalysis, 10(15): 8201–8211
Ren C, Yang P, Sun J, Bi E Y, Gao J, Palmer J, Zhu M, Wu Y, Liu J (2021a). A bioinspired molybdenum catalyst for aqueous perchlorate reduction. Journal of the American Chemical Society, 143(21): 7891–7896
Ren Z, Bergmann U, Leiviskä T (2021b). Reductive degradation of perfluorooctanoic acid in complex water matrices by using the UV/sulfite process. Water Research, 205: 117676
Schaefer C E, Andaya C, Urtiaga A, McKenzie E R, Higgins C P (2015). Electrochemical treatment of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in groundwater impacted by aqueous film forming foams (AFFFs). Journal of Hazardous Materials, 295: 170–175
Scott S L (2018). A matter of life (time) and death. ACS Catalysis, 8(9): 8597–8599
Shekhar S, Ryberg P, Hartwig J F, Mathew J S, Blackmond D G, Strieter E R, Buchwald S L (2006). Reevaluation of the mechanism of the amination of aryl halides catalyzed by BINAP-ligated palladium complexes. Journal of the American Chemical Society, 128(11): 3584–3591
Singh U K, Strieter E R, Blackmond D G, Buchwald S L (2002). Mechanistic insights into the Pd(BINAP)-catalyzed amination of aryl bromides: kinetic studies under synthetically relevant conditions. Journal of the American Chemical Society, 124(47): 14104–14114
Standardization Administration of China (2022). National Standard of the People’s Republic of China: GB 5749-2022 Standards for Drinking Water Quality
Strieter E R, Buchwald S L (2006). Evidence for the formation and structure of palladacycles during Pd-catalyzed C−N bond formation with catalysts derived from bulky monophosphinobiaryl ligands. Angewandte Chemie International Edition, 45(6): 925–928
Su J F, Kuan W F, Chen C L, Huang C P (2020). Enhancing electrochemical nitrate reduction toward dinitrogen selectivity on Sn-Pd bimetallic electrodes by surface structure design. Applied Catalysis A, General, 606: 117809
Tacke T, Vorlop K D (1993). Kinetische charakterisierung von katalysatoren zur selektiven entfernung von nitrat und nitrit aus wasser. Chemieingenieurtechnik (Weinheim), 65(12): 1500–1502
Van Santen R, Klesing A, Neuenfeldt G, Ottmann A (2001). Method for removing chlorate ions from solutions. U.S. Patent US6270682B1
Vorlop K D, Hörold S, Pohlandt K (1992). Optimierung von trägerkatalysatoren zur selektiven nitritentfernung aus wasser. Chemieingenieurtechnik (Weinheim), 64(1): 82–83
Vorlop K D, Tacke T (1989). Erste schritte auf dem weg zur edelmetallkatalysierten nitrat-und nitrit-entfernung aus trinkwasser. Chemieingenieurtechnik (Weinheim), 61(10): 836–837
Wang Y, Liu J, Wang P, Werth C J, Strathmann T J (2014). Palladium nanoparticles encapsulated in core-shell silica: a structured hydrogenation catalyst with enhanced activity for reduction of oxyanion water pollutants. ACS Catalysis, 4(10): 3551–3559
Wang Y, Xu A, Wang Z, Huang L, Li J, Li F, Wicks J, Luo M, Nam D H, Tan C S, Ding Y, Wu J, Lum Y, Dinh C T, Sinton D, Zheng G, Sargent E H (2020). Enhanced nitrate-to-ammonia activity on copper-nickel alloys via tuning of intermediate adsorption. Journal of the American Chemical Society, 142(12): 5702–5708
Webb J D, Macquarrie S, Mceleney K, Crudden C M (2007). Mesoporous silica-supported Pd catalysts: An investigation into structure, activity, leaching and heterogeneity. Journal of Catalysis, 252(1): 97–109
Werth C J, Yan C, Troutman J P (2020). Factors impeding replacement of ion exchange with (electro) catalytic treatment for nitrate removal from drinking water. ACS ES&T Engineering, 1(1): 6–20
Wu Y, Cai S, Wang D, He W, Li Y (2012). Syntheses of water-soluble octahedral, truncated octahedral, and cubic Pt−Ni nanocrystals and their structure-activity study in model hydrogenation reactions. Journal of the American Chemical Society, 134(21): 8975–8981
Wu Z Y, Karamad M, Yong X, Huang Q, Cullen D A, Zhu P, Xia C, Xiao Q, Shakouri M, Chen F Y, Kim J Y T, Xia Y, Heck K, Hu Y, Wong M S, Li Q, Gates I, Siahrostami S, Wang H (2021). Electrochemical ammonia synthesis via nitrate reduction on Fe single atom catalyst. Nature Communications, 12(1): 2870
Ye T, Banek N A, Durkin D P, Hu M, Wang X, Wagner M J, Shuai D (2018). Pd nanoparticle catalysts supported on nitrogen-functionalized activated carbon for oxyanion hydrogenation and water purification. ACS Applied Nano Materials, 1(12): 6580–6586
Ye X, Nan J, Ge Z, Xiao Q, Liu B, Men Y, Liu J (2022). Simultaneous removal of iron, manganese, and ammonia enhanced by preloaded MnO2 on low-pressure ultrafiltration membrane. Journal of Membrane Science, 656: 120641
Yin Y B, Guo S, Heck K N, Clark C A, Conrad C L, Wong M S (2018). Treating water by degrading oxyanions using metallic nanostructures. ACS Sustainable Chemistry & Engineering, 6(9): 11160–11175
Yu Y H, Chiu P C (2014). Kinetics and pathway of vinyl fluoride reduction over rhodium. Environmental Science & Technology Letters, 1(11): 448–452
Yuan A, Zhao H, Shan W, Sun J-F, Deng J, Liu H, Liu R, Liu J-F (2021). The binding strength of reactive H*: a neglected key factor in Rh-catalyzed environmental hydrodefluorination reaction. ACS ES&T Engineering, 1(6): 1036–1045
Zhang Y, Hurley K D, Shapley J R (2011). Heterogeneous catalytic reduction of perchlorate in water with Re−Pd/C catalysts derived from an oxorhenium(V) molecular precursor. Inorganic Chemistry, 50(4): 1534–1543
Zhang Z, Xu Y, Shi W, Wang W, Zhang R, Bao X, Zhang B, Li L, Cui F (2016). Electrochemical-catalytic reduction of nitrate over Pd−Cu/γAl2O3 catalyst in cathode chamber: enhanced removal efficiency and N2 selectivity. Chemical Engineering Journal, 290: 201–208
Zhao H P, Van Ginkel S, Tang Y, Kang D W, Rittmann B, Krajmalnik-Brown R (2011). Interactions between perchlorate and nitrate reductions in the biofilm of a hydrogen-based membrane biofilm reactor. Environmental Science & Technology, 45(23): 10155–10162
Zhuang Y, Ahn S, Seyfferth A L, Masue-Slowey Y, Fendorf S, Luthy R G (2011). Dehalogenation of polybrominated diphenyl ethers and polychlorinated biphenyl by bimetallic, impregnated, and nanoscale zerovalent iron. Environmental Science & Technology, 45(11): 4896–4903
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Financial support was provided by the U.S. National Science Foundation (CBET-1932942).
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Highlights
• Advances, challenges, and opportunities for catalytic water pollutant reduction.
• Cases of Pd-based catalysts for nitrate, chlorate, and perchlorate reduction.
• New functionalities developed by screening and design of catalytic metal sites.
• Facile catalyst preparation approaches for convenient catalyst optimization.
• Rational design and non-decorative effort are essential for future work.
Author Biography
Dr. Jinyong Liu is currently an Associate Professor at the Department of Chemical and Environmental Engineering, University of California, Riverside (UCR), USA. He received his Bachelor’s degree in Chemistry and Master’s degree in Environmental Science & Engineering from Tsinghua University, China and his Ph.D. degree in Environmental Engineering from the University of Illinois at Urbana-Champaign, USA. After the postdoctoral training at Colorado School of Mines, he joined UCR in 2016. The ongoing research topics in his lab include (i) degradation of per- and polyfluoroalkyl substances (PFAS), (ii) catalytic reduction of oxyanions, and (iii) transition metal chemistry for environmental applications.
Dr. Liu is the recipient of the Chinese-American Professors in Environmental Engineering and Science (CAPEES) Young Investigator Award (2022), the Association of Environmental Engineering and Science Professors (AEESP) Paul V. Roberts Outstanding Doctoral Dissertation Award for Advisor (2021), New Engineer to Watch by Water Environment Research (2021), Excellence in Review Award of Environmental Science & Technology Letters (2018), American Chemical Society (ACS) C. Ellen Gonter Environmental Chemistry Award (2014), and ACS Graduate Student Award in Environmental Chemistry (2013). His PhD students at UCR have received one AEESP Paul V. Roberts Outstanding Doctoral Dissertation Award (2021), four ACS C. Ellen Gonter Environmental Chemistry Awards (2019, 2020, 2021, 2022), three ACS Graduate Student Awards in Environmental Chemistry (2019, 2020, 2021), one ACS Undergraduate Award in Environmental Chemistry (2019), and two American Water Works Association (AWWA) Scholarships (2018, 2019). The undergraduate and high school students in Dr. Liu’s lab continued their higher education in Chemical Engineering and Chemistry majors at Stanford University and Massachusetts Institute of Technology. Dr. Liu is currently the member of Editorial Board for Frontiers of Environmental Science & Engineering, Water Environment Research, and Environmental Research.
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Liu, J., Gao, J. Catalytic reduction of water pollutants: knowledge gaps, lessons learned, and new opportunities. Front. Environ. Sci. Eng. 17, 26 (2023). https://doi.org/10.1007/s11783-023-1626-z
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DOI: https://doi.org/10.1007/s11783-023-1626-z