CdS/g‐C₃N₄ Hybrids with Improved Photostability and Visible Light Photocatalytic Activity

Abstract

Novel composite photocatalysts consisting of CdS and graphitic carbon nitride (CdS/g‐C3N4) with different ratios of CdS were prepared. The CdS/g‐C3N4 composite photocatalysts were characterized in detail and their photocatalytic activity was evaluated by using rhodamine B and colorless metronidazole as probes. Compared with pure g‐C3N4, the CdS/g‐C3N4 composite exhibits significantly enhanced photocatalytic activity under visible‐light irradiation. More importantly, g‐C3N4 substantially reinforces the photostability of CdS nanowires even in a nonsacrificial system. The synergistic effect between CdS and g‐C3N4 is found to be primarily responsible for enhancement of the separation of photogenerated electrons and holes, which helps improve the photocatalytic performance. A probable photodegradation process of metronidazole was proposed based on an analysis of the degradation products. This study provides new insight into the preparation of highly efficient and stable sulfide‐based composite photocatalysts and facilitates their application in a number of environmentally sensitive areas.

Facile and Scale Up Synthesis of Red Phosphorus-Graphitic Carbon Nitride Heterostructures for Energy and Environment Applications

“…The fundamental absorption edge of the as-prepared and milled g-C 3 N 4 occurred at ~450 nm, which is the characteristic absorption wavelength of g-C 3 N 4 41. The RPh-g-C 3 N 4 heterostructures showed significantly enhanced absorption in the visible region accompanied by a shift in the red absorption edge compared to the as-prepared P-g-C 3 N 4 and milled B-g-C 3 N 4 , which might be due to the combined synergistic effects of the narrow band gap and light harvesting characteristics of RPh and g-C 3 N 4 62242. These results indicate that the RPh-g-C 3 N 4 heterostructure is active in the wide visible light range and may produce photoinduced charge carriers under visible light photoirradiation, which is highly favorable for the photocatalytic reactions.…”

“…S4). Figure S5a–d shows the C 1s high resolution spectra of P-g-C 3 N 4 , B-g-C 3 N 4 , 1-RPh-g-C 3 N 4 , and 2-RPh-g-C 3 N 4 heterostructures, which shows two distinct peaks at 284.53 and 287.99 eV due to the two different chemical state of carbon, i.e., sp2 hybridization and C-N bonding present in the samples2241. Figure 3a–d shows the N 1s high resolution core level spectra of P-g-C 3 N 4 , B-g-C 3 N 4 , 1-RPh-g-C 3 N 4 , and 2-RPh-g-C 3 N 4 with the corresponding deconvoluted Gaussian fitted peaks.…”

“…For these purposes, tremendous efforts have been focused on polymeric-layered materials, particularly graphitic-like carbon nitride (g-C 3 N 4 ), because it has a suitable band gap (~2.7 eV) for the effective utilization of visible light for the photocatalytic reaction2122. The physicochemical stability owing to its cadenced CN framework and easy synthesis process make it suitable for a range of applications, including hydrogen production and the degradation of organic pollutants2122232425.…”

“…The physicochemical stability owing to its cadenced CN framework and easy synthesis process make it suitable for a range of applications, including hydrogen production and the degradation of organic pollutants2122232425. Despite this, the catalytic efficiency of g-C 3 N 4 in a wide spectrum of the solar energy is still far from satisfactory because of the rapid photoinduced e − /h + recombination rate and the limited specific surface area24252627.…”

Facile Synthesis of Novel Redox-Mediator-free Direct Z-Scheme CaIn2S4 Marigold-Flower-like/TiO2 Photocatalysts with Superior Photocatalytic Efficiency

“…To date, TiO 2 , CdS, ZnS, Zn 2 GeO 4 , ZnSnO 3 , ZnO/RGO, BiVO 4 , BiVO 4 /FeVO 4 and CdS/g-C 3 N 4 , photocatalysts have been used for the decomposition of MTZ, [32][33][34][35][36][37][38] whereas only a single study has investigated ISN degradation, using TiO 2 and ZnO photocatalysts. 39 No detailed study has been performed on the degradation of these pharmaceuticals using a direct Z-scheme photocatalytic system.…”