화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.474, 34-40, 2016
Coverage control of CdSe quantum dots in the photodeposition on TiO2 for the photoelectrochemical solar hydrogen generation
CdSe quantum dots (QDs) have successfully been formed on the TiO2 surface by the photodeposition of Se QDs and their subsequent transformation into CdSe QDs (CdSe/TiO2) (Fujishima et al., 2014). The addition of mercaptoacetic acid (MAA) in the second step of the two-step photodeposition process significantly decreases the CdSe particle size and the contact angle against the TiO2 surface to increase the TiO2-surface coverage by CdSe QDs with the particle size distribution sharpened. X-ray photoelectron and Raman spectroscopy measurements indicated that MAA is densely chemisorbed on the surface of CdSe QDs through Cd-S bond, whereas sparsely adsorbed on the TiO2 surface. Photoelectrochemical (PEC) cells using CdSe/TiO2 as the photoanode for hydrogen (H-2) generation from aqueous sulfide solution were fabricated. The rate of H-2 generation strongly depends on the concentration of MAA (C) added in the photoanode preparation, and the photoanode prepared at C = 0.04 mM affords a maximum solar-to-hydrogen conversion efficiency of 0.028%. (C) 2016 Published by Elsevier Inc.