Co-sensitized TiO2 electrodes with different quantum dots for enhanced hydrogen evolution in photoelectrochemical cells

• DOI: 10.1007/s10800-019-01299-x
• Publication Date: 2019-03-06T12:32:35Z
• Authors: Andrea Cerdán-Pas...; Tzarara López-Luke; Isaac Zarazúa; Elder De la Rosa; Rosalba Fuentes-R...; K. C. Sanal; Alejandro Alatorr...
• Keywords: 01 natural sciences; 7. Clean energy; 0104 chemical sciences

A comparative study of hydrogen evolution in devices based on cadmium chalcogenides quantum dots (CdS, CdSe and CdTe) and its combinations, sensitizing TiO2 was carried out. A maximum photocurrent of 2.7 mA cm−2 at 0 V bias, and a solar-to-hydrogen (STH) conversion efficiency of 0.9%, was obtained with CdSe QDs due to its wide absorption range. The co-sensitized device with CdS–CdSe QDs showed a higher photocurrent of 3.9 mA cm−2 with an STH of 1.2%. The improvement in hydrogen generation for electrodes sensitized with CdS in combination with CdSe or CdTe QDs, was attributed to the increased light absorption and appropriate band alignment for the enhanced charge transport.