Enhanced photocatalytic pure water splitting of porous g-C3N4/CdS composite by the bimetallic phosphide. Issue 3 (June 2022)

• Record Type: Journal Article
• Authors: Gong, Qingna; Zhou, Yu; Wang, Ruixin; Jiao, Weizhou
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 3(2022)
• Publication Date: 2022-06
• Subjects: Photocatalysis -- Pure water splitting -- Porous g-C3N4 -- Bimetallic phosphide -- CdS; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2022.108046
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Here, a novel CoNiP nanoclusters-decorated photocatalyst consisted of porous g-C3 N4 (PCN) and CdS were reported for the pure water splitting. Under visible light (λ ≥ 400 nm), the activities and durability for photocatalytic water splitting over the PCN-CdS composite can be importantly improved by CoNiP. And the photocatalytic H2 -evolution rate could be maximized to 122.08 μmol g ‐1 h ‐1 for pure water-splitting through regulating the loading amount of CoNiP and the ratio of Co, Ni and P, which are all larger than those of PCN-CdS, PCN-CdS-Pt, PCN-CdS-Co2 P and PCN-CdS-Ni2 P. Comparing to the single metal phosphides (Co2 P and Ni2 P), the higher photocatalytic activities of PCN-CdS enhanced by the bimetallic phosphide (CoNiP) are on account of the extended light absorption, more exposed active sites, the regulated electronic structure, accelerated electrons transfer, the more negative Fermi energy and more trapped electrons in CoNiP. In addition, the PCN-CdS-CoNiP composite exhibits the high stability during the 3 cycling tests for 12 h, due to its stable structure resulted by the reinforced chemical connection between PCN and CoNiP in a form of P + -P δ- -Co δ+ /Ni δ+, in which the positive charge center (P + ) originates from the replacement of C in PCN by P. This research indicates that the bimetallic phosphide could be a promising candidate of precious metals substitutes in photocatalyst system with higher activities. Graphical Abstract: ga1 Highlights: Cobalt-Nickel bimetallic phosphide (CoNiP) is integrated onto the porous g-C3 N4 (PCN)/CdS composite. PCN-CdS-CoNiP exhibits an improved photocatalytic H2 evolution, compared to PCN-CdS, PCN-CdS-Pt, PCN-CdS-Co2 P (or Ni2 P). Regulated electronic structure and the more negative Fermi energy are mainly responsible for the facilitated H2 evolution. PCN-CdS-CoNiP is highly stable due to the strong chemical connection between PCN and CoNiP in a form of P + -P δ- -Co δ+ /Ni δ+ .