Performance of amine-modified CdS-D@ZIF-8 nanocomposites for enhanced photocatalytic H2 evolution

• Published in: International journal of hydrogen energy 2023-08, Vol.48 (66), p.25645-25659
• Main Authors: Ayyob, Muhammad, Sun, Zhichao, Liu, Ying-Ya, Wang, Yao, Wang, Anjie
• Format: Article
• Language: English
• Subjects: CdS; Diethylenetriamine; Photocatalytic H2 evolution; S-Scheme nanocomposite; ZIF-8
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2023.03.304

The exploration of an efficient photocatalyst for H2 evolution directly from water splitting is highly desirable due to the current environmental and energy situation. The present work successfully used a solvothermal method to synthesize organic-inorganic CdS-diethylenetriamine (CdS-D) nanorods (NRs). The amine-modified CdS-D@ZIF-8 nanocomposite materials were prepared using the self-assembly method with different ZIF-8 nanocrystals (NCs) weight ratios. At λ ≥ 420 nm wavelength, the optimized CdS-D@ZIF-8 (CZ-2) nanocomposite with 5.0 wt% loading of ZIF-8 NCs showed the highest performance of 2293.9 μmol g−1 h−1 H2 evolution and an apparent quantum yield (AQY) of 4.95%. The CZ-2 nanocomposite's activity was 114.69, 5.25, and 1.32 times higher than that of ZIF-8 NCs (20.0 μmol g−1 h−1), CdS-D NRs (436.4 μmol g−1 h−1) and 1.0 wt% Pt/CdS-D (1737.3 μmol g−1 h−1), respectively. The cyclic photostability of the prepared CZ-2 nanocomposite remained unchanged after six consecutive cycles. The UV-DRS, electrochemical measurements, and Mott-Schottky (MS) analysis were performed to explain the band edge positions for CdS-D NRs and ZIF-8 NCs. The detailed S-scheme charge transfer mechanism of the as-prepared catalysts was also studied using the density functional theory (DFT). This work provides vital information for the controllable synthesis of ZIF-8-modified S-scheme nanocomposites for solar energy utilization. [Display omitted] •Novel amine-modified CdS-D@ZIF-8 nanocomposites were built using a self-assembly approach.•The prepared CdS-D@ZIF-8 (5.0 wt% ZIF-8) nanocomposite showed excellent photocatalytic H2 evolution.•The CZ-2 nanocomposite showed excellent cyclic stability and recyclability.•UV-DRS, EIS, and Mott-Schottky analysis were performed to determine the band edge position.•The charge transfer mechanism for enhanced photocatalytic H2 evolution was proposed.