Abstract

As one of the most effective strategies for the storage and utilization of solar energy, the development of pho-tocatalytic technology has received extensive attention. The core work, the design and modification of photo -catalysts, is very significance. Herein, we prepared C, N co-doped Co3O4 (CN-CoO) by a simple method and composited it with CdS to form CN-CoO/CdS p-n type heterojunctions. The prepared materials are characterized by numerous tests, such as XRD, SEM, TEM, XPS, and photoelectrochemical measurement. Due to the excellent electrochemical performance of CN-CoO and the built-in electric field in CN-CoO/CdS, the efficient separation of photogenerated charges is realized. Compared with CdS (1.11 ns), the average carrier lifetimes of the 15%CN-CoO/CdS (1.63 ns) is prolonged, which enhances photocatalytic hydrogen evolution activity of the composite materials. The hydrogen evolution rate of the optimal 15%CN-CoO/CdS is 6.78-fold greater than that of pristine CdS, and is as high as 64.36 mmol.g? 1.h- 1. Meanwhile, the 15%CN-CoO/CdS exhibits outstanding chemical stability after cyclic hydrogen production experiment for 30 h, and its apparent quantum efficiency (AQE) reaches 27.47% under monochromatic light at 405 nm. In addition, the formation process and photocatalytic hydrogen evolution mechanism of the CN-CoO/CdS p-n type heterojunctions are analyzed and discussed. This work provides a new idea for the construction of efficient photocatalytic heterojunctions through the modifi-cation and combination of semiconductors.