Highly efficient charge transfer in CdS-Covalent organic framework nanocomposites for stable photocatalytic hydrogen evolution under visible light

Abstract A facile and effective impregnation combined with photo-deposition approach was adopted to deposit CdS nanoparticles on covalent organic framework (CTF-1). In this system, CTF-1 not only acted as supporter but also served as photocatalyst and electron donor. The performance of the obtained CdS-CTF-1 nanocomposite was evaluated by H2 evolution reaction under visible light irradiation. As a result, CdS-CTF-1 exhibited high H2 production from water, far surpassing the CdS/CTF-1 nanocomposite, in which CdS was deposited via solvothermal method. The high activity of CdS-CTF-1 was attributed to the confined CdS nanoparticles with small size, leading to expose more active sites. In addition, time-resolved spectroscopy indicated that the superior performance of CdS-CTF-1 also can be ascribed to the fast electron transfer rate and injection efficiency (KET = 0.18×109 s–1, ηinj = 39.38%) between CdS and CTF-1 layers, which are 3.83 times faster and 4.84 times higher than that of CdS/CTF-1 nanocomposite. This work represents the first example on using COFs as a support and electron-donor for fabricating novel CdS-COF nanocomposite system and its potential application in solar energy transformations.