Electric‐assisted strategy enhances the photocatalytic performance of mixed‐dimensional CdS/MoS₂ photocatalysts

Abstract

As an effective semiconductor catalyst, cadmium sulfide (CdS) is used in the field of split water hydrogen evolution because of its suitable band gap (~2.4 eV), good photocatalysis activity. However, the rapid recombination of photogenerated electron–hole pairs limits the application of CdS in the field of catalytic hydrogen evolution. Here, we synthesize a CdS/MoS2 mixed‐dimensional heterojunction by a simple hydrothermal method. In this process, CdS nanoparticles were supported on MoS2 nanosheets, where MoS2 acts as a loading platform and co‐catalyst to improve the photocatalytic performance of CdS. A series of characterizations confirmed that CdS nanoparticles with a size of approximately 130 nm were uniformly grown on the surface of MoS2 nanosheets. Photoelectrochemical (PEC) tests show that this CdS/MoS2 mixed‐dimensional heterojunction has enhanced photocatalysis hydrogen evolution activity, which is due to the CdS/MoS2 mixed‐dimensional heterojunction can promote the separation of photogenerated electron–hole pairs and positive synergy of MoS2 nanosheets as a co‐catalyst. In addition, a new electrically assisted method is used to enhance the photocatalytic activity, and the photocatalytic performance of the CdS/MoS2 mixed‐dimensional heterojunction is improved by nearly four times when a voltage of 0.6 V is applied. This phenomenon is attributed to the fact that providing an appropriate voltage can further promote the separation of photogenerated electron–hole pairs and rapid carrier mobility, thereby effectively improve the photocatalytic activity of the photocatalyst. This work provides a good guiding significance for the design and construction of high‐performance hydrogen evolution catalysts.

Aluminum-doped cadmium sulfide homojunction photoelectrode with optimal film quality and water-splitting performance

“…Compared with the work of Shin's group, our photoanode with an 8.1 mA cm −2 photocurrent density exceeded the traditional binary MoS 2 /CdS heterojunction with a photocurrent density of 1.2 mA cm −2 . 55 Additionally, the 0.58 V potential for dark current generation was close to Qi's report of 0.6 V. 56 Considering that the dark current is typically generated by the oxidation of photoanode materials, this result represented successful inhibition of self-corrosion accompanied by promising PEC performance.…”

Photoinduced reduction of aquatic Cr(VI) on CdS/MoS 2 heterostructures

“…Intense XRD peaks for CdS NRs is an indication of its high degree of crystallinity [40]. Typically, photocatalytic performance is closely related to the crystallinity of the photocatalyst, higher crystallinity, usually, promotes the photocatalytic reaction.…”