Plasmonic hot electron transfer-induced multicolor MoO3-x-based chromogenic system for visual and colorimetric determination of silver(I)

• Published in: Mikrochimica acta (1966) Vol. 187; no. 2; p. 120
• Main Authors: Du, Jiayan, Wang, Junren, Deng, Yuequan, He, Yi
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.02.2020; Springer Nature B.V
• Subjects: Analytical Chemistry; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Colorimetry; Electron transfer; Hot electrons; Light emitting diodes; Microengineering; Molybdenum oxides; Molybdenum trioxide; Nanochemistry; Nanoparticles; Nanostructure; Nanotechnology; Original Paper; Oxidation; Plasmonics; Silver; White light; Water sample; Colorimetry; Photo-oxidation; Nanosheet
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-020-4108-z

A plasmonic hot electron transfer-induced multicolor chromogenic system is described for label-free visual colorimetric determination of silver(I). The chromogenic system consists of plasmonic MoO 3-x nanosheets with oxygen vacancies and Ag(I). Under white light-emitting diode (LED) excitation, energetic hot hole-electron pairs are formed on the surface of the blue MoO 3-x nanosheets. The resulting hot electrons are transferred to Ag(I) upon which it becomes reduced. This results in the generation of yellow silver nanoparticles. Simultaneously, the hot holes lead to the oxidation of the MoO 3-x nanosheets to yield colorless MoO 3 nanosheets. Similarly, energetic hot hole-electron pairs can also be generated on the surface of AgNPs under white LED irradiation, which contributes to the reduction of Ag(I) and the oxidation of MoO 3-x . Overall, a colorful transition from blue to green and finally to yellow can be observed. This multicolor chromogenic system was applied to the colorimetric determination of Ag(I) in the 33–200 μM concentration range and a 0.66 μM limit of detection, at analytical wavelengths of 430 and 760 nm. The method also is amenable to semi-quantitative visual determination of Ag(I). Graphical abstract Schematic representation of plasmonic hot electron transfer-induced multicolor MoO 3-x -based chromogenic system for visual and colorimetric determination of silver(I).