Preparation of an AgI/CuBi2O4 heterojunction on a fluorine-doped tin oxide electrode for cathodic photoelectrochemical assays: application to the detection of L-cysteine
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Photocathodic methods in photoelectrochemical (PEC) analysis are based on the use of functional photocathodes. Heterojunction cathodes consisting of different kinds of semiconductors are being considered as favorite schemes when compared to the single-component ones. A semiconductor heterojunction between CuBi2O4 (CBO) and other semiconductors has not been exploited in PEC assays so far. Herein, CBO nanospheres were initially electrochemically deposited on a fluorine-doped tin oxide (FTO) conductive glass and then coupled to chemically deposited AgI nanoparticles to obtain an electrode of type AgI/CBO/FTO. It was applied as a cathode in the PEC detection of L-cysteine as a model analyte. The sensor can selectively detect L-cysteine, and it is assumed that this is due to the selective interaction between the L-cysteine and both copper and silver via the formation of Cu-S and Ag-S bonds. The photocurrent of the electrode increases linearly with the logarithm of the cysteine concentration in the range from 0.1 and 50 μM, and the detection limit is 0.1 μM.
KeywordsPhotoelectrochemical sensing CuBi2O4 AgI Heterojunction Photocathodic sensing
This work was supported by the National Natural Science Foundation of China (Grant Nos. 21675080, and 21705059) and the Natural Science Foundation of Jiangsu Province (Grant No. BK20170073).
Compliance with ethical standards
The authors declare that they have no competing interests.
- 3.He YY, Ge JY, Zhao CZ (2016) Photoelectrochemical response and application of ZnO nanorods photoelectrode to riboflavin. Chem J Chin Univ 37:2144–2149Google Scholar
- 11.Wang GL, Liu KL, Shu JX, Gu TT, Wu XM, Dong YM, Li ZJ (2015) A novel photoelectrochemical sensor based on photocathode of PbS quantum dots utilizing catalase mimetics of bio-bar-coded platinum nanoparticles/G-quadruplex/hemin for signal amplification. Biosens Bioelectron 69:106–112CrossRefGoogle Scholar
- 24.Kong QK, Cui K, Zhang LN, Wang YH, Sun JL, Ge SG, Zhang Y, Yu JH (2018) "On-off-on" photoelectrochemical/visual lab-on-paper sensing via signal amplification of CdS quantum dots@leaf-shape ZnO and quenching of Au-modified prism-anchored octahedral CeO2 nanoparticles. Anal Chem 90:11297–11304CrossRefGoogle Scholar