Key Laboratory of Materials for Energy Conversion, Chinese Academy of Sciences, Department of Materials Science and Engineering, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), University of Science and Technology of China (USTC), Hefei, 230026, China.
Nanoscale. 2016 Feb 28;8(8):4748-56. doi: 10.1039/c6nr00160b.
Photocatalytic hydrogen production from water in a noble-metal-free system has attracted much attention in recent years. Herein we report on the use of core/shell cadmium sulfide/graphitic carbon nitride (CdS/g-C3N4) heterojunction nanorods modified by nickel hydroxide (Ni(OH)2) as a highly efficient photocatalyst for visible light-driven hydrogen production from water. Due to efficient separation of the photoexcited charge carriers in the CdS/g-C3N4 core/shell nanorods and the synergistic effect of Ni(OH)2, the optimal hydrogen evolution rate over Ni(OH)2-CdS/g-C3N4 is 115.18 μmol h(-1) mg(-1) under visible light irradiation (λ > 420 nm), which is ∼26 times higher than the CdS/g-C3N4 nanorod composite without Ni(OH)2 and ∼7 times better than the 0.5 wt% Pt-CdS/g-C3N4 nanorod composite. The apparent quantum efficiency is ∼16.7% at an excitation of 450 nm. During photocatalysis, no degradation of Ni(OH)2 was observed based on the XPS data, indicating that it is a robust cocatalyst. Moreover, the present photocatalyst showed excellent photocatalytic stability for hydrogen production and the turnover number (TON) reached ∼24,600 over 90 hours.
近年来，无贵金属体系中的光催化水制氢引起了广泛关注。在此，我们报告了一种新型的高效光催化剂，即镍氢氧化物（Ni(OH)2）修饰的核壳硫化镉/石墨相氮化碳（CdS/g-C3N4）异质结纳米棒，用于可见光驱动的水制氢反应。由于在 CdS/g-C3N4 核壳纳米棒中光生载流子的有效分离以及 Ni(OH)2 的协同作用，在可见光（λ>420nm）照射下，Ni(OH)2-CdS/g-C3N4 的最佳产氢速率为 115.18 μmol h(-1) mg(-1)，是没有 Ni(OH)2 的 CdS/g-C3N4 纳米棒复合材料的 26 倍，是 0.5wt%Pt-CdS/g-C3N4 纳米棒复合材料的 7 倍。在 450nm 的激发下，其表观量子效率约为 16.7%。根据 XPS 数据，在光催化过程中没有观察到 Ni(OH)2 的降解，表明它是一种稳定的助催化剂。此外，该光催化剂在水制氢反应中表现出优异的光催化稳定性，在 90 小时内的周转数（TON）达到约 24600。
