Constructing Sequential Type II Heterojunction CQDs/Bi 2 S 3 /TiNbO Photoanode with Superior Charge Transfer Capability Toward Stable Photoelectrochemical Water Splitting

作者：Yanjie Pan, Zhenbiao Dong, Dongmei Qin, Bao-Peng Liu, Lulu Cui, Sheng Han, Hualin Lin · 发表于：ACS Applied Materials & Interfaces · 年份：2024 · DOI：10.1021/acsami.3c17726 · 被引用次数：42 · 研究领域：Advanced Photocatalysis Techniques、Quantum Dots Synthesis And Properties、Perovskite Materials and Applications

Efficient charge transfer and light-trapping units are pivotal prerequisites in the realm of Ti-based photoanode photoelectrochemical (PEC) water splitting. In this work, we successfully synthesized a ternary carbon quantum dots/Bi 2 S 3 quantum dots/Nb-doped TiO 2 nanotube arrays (CQDs/Bi 2 S 3 /TiNbO) composite photoanode for PEC water splitting. CQDs/Bi 2 S 3 /TiNbO composite photoanode exhibited a considerably elevated photocurrent density of 8.80 mA cm –2 at 1.23 V vs the reversible hydrogen electrode, which was 20.00 times better than that of TiO 2 (0.44 mA cm –2 ). Furthermore, the CQDs/Bi 2 S 3 /TiNbO composite photoanode attested to exceptional stability, maintaining 92.54% of its initial current after 5 h of stability measurement. Nb-doping boosted the electrical conductivity, facilitating charge transfer at the solid–liquid interface. Moderate amounts of Bi 2 S 3 quantum dots (QDs) and CQDs deposited on TiNbO provided abundant active sites for the electrolyte–photoanode interaction. Simultaneously, Bi 2 S 3 QDs and CQDs synergistically functioned as light-trapping units to broaden the light absorption range from 396 to 530 nm, stimulating increased carrier generation within the composite photoanode. In comparison with pristine TiO, CQDs/Bi 2 S 3 /TiNbO photoanodes possessed a superior ability to promote interfacial reactions. This study may provide a strategy for developing high-performance Ti-based photoanodes with efficient charge transfer and light trapping unit...