Effect of Surface Trap States on Photocatalytic Activity of Semiconductor Quantum Dots

• DOI: 10.1021/acs.jpcc.8b01206
• Publication Date: 2018-04-12T09:39:01Z
• Authors: Haoyang Zou; Chunwei Dong; Suyu Li; Chan Im; Mingxing Jin; Shiyu Yao; Tian Cui; Wenjing Tian; Yi Liu; Hao Zhang
• Keywords: Hydrothermal Synthesis; Charge carrier; Trap (plumbing); Crystal (programming language)

Semiconductor quantum dots (QDs) are promising photocatalysts for water splitting due to the large specific area, but influence of surface trap states on photocatalytic activity QDs is still not fully understood yet. To answer this question, CdSe with same morphology, diameter, crystal structure, and energy level prepared following a hydrazine hydrate (N2H4) promoted synthesis strategy conventional hydrothermal method. Through various characterizations analysis, it found that synthesized (H-CdSe QDs) have high concentration Cd-involved shallow electron states, which seriously hinder charge separation transfer between cocatalysts. In contrast, N2H4 provides an energy-saving, low-cost, facile pathway eliminate traps, ensuring efficient H2 production in QDs. As result, N2H4-promoted (N-CdSe produce 44.5 mL (1998 μmol) 7 h, roughly 1.6 times higher than H-CdSe (27.5 mL, 1236 μmol). Because widespread semiconductor QDs, believed our study valuable guidance design preparation photocatalysis.