Efficient photocatalytic hydrogen peroxide generation coupled with selective benzylamine oxidation over defective ZrS3 nanobelts
Zhangliu Tian, Cheng Han, Yao Zhao, Wenrui Dai, Xu Lian, Yanan Wang, Yue Zheng, Yi Shi, Xuan Pan, Zhichao Huang, Hexing Li, Wei Chen
Abstract
Abstract Photocatalytic hydrogen peroxide (H 2 O 2 ) generation represents a promising approach for artificial photosynthesis. However, the sluggish half-reaction of water oxidation significantly limits the efficiency of H 2 O 2 generation. Here, a benzylamine oxidation with more favorable thermodynamics is employed as the half-reaction to couple with H 2 O 2 generation in water by using defective zirconium trisulfide (ZrS 3 ) nanobelts as a photocatalyst. The ZrS 3 nanobelts with disulfide (S 2 2− ) and sulfide anion (S 2− ) vacancies exhibit an excellent photocatalytic performance for H 2 O 2 generation and simultaneous oxidation of benzylamine to benzonitrile with a high selectivity of >99%. More importantly, the S 2 2− and S 2− vacancies can be separately introduced into ZrS 3 nanobelts in a controlled manner. The S 2 2− vacancies are further revealed to facilitate the separation of photogenerated charge carriers. The S 2− vacancies can significantly improve the electron conduction, hole extraction, and kinetics of benzylamine oxidation. As a result, the use of defective ZrS 3 nanobelts yields a high production rate of 78.1 ± 1.5 and 32.0 ± 1.2 μmol h −1 for H 2 O 2 and benzonitrile, respectively, under a simulated sunlight irradiation.