Key points are not available for this paper at this time.
Generation of hydrogen by photochemical, electrochemical, and other means is a vital area of research today, and a variety of materials have been explored as catalysts for this purpose. C 3 N 4, MoS 2, and nitrogenated RGO (NRGO) are some of the important catalytic materials investigated for the hydrogen evolution reaction (HER) reaction, but the observed catalytic activities are somewhat marginal. Prompted by preliminary reports that covalent cross-linking of 2D materials to generate heteroassemblies or nanocomposites may have beneficial effect on the catalytic activity, we have synthesized nanocomposites wherein C 3 N 4 is covalently bonded to MoS 2 or NRGO nanosheets. The photochemical HER activity of the C 3 N 4 –MoS 2 nanocomposite is found to be remarkable with an activity of 12778 μmol h –1 g –1 and a turnover frequency of 2.35 h –1 . The physical mixture of C 3 N 4 and MoS 2, on the other hand, does not exhibit notable catalytic activity. Encouraged by this result, we have studied electrochemical HER activity of these composites as well. C 3 N 4 –MoS 2 shows superior activity relative to a physical mixture of MoS 2 and C 3 N 4 . Density functional theory calculations have been carried out to understand the HER activity of the nanocomposites. Charge-transfer between the components and greater planarity of cross-linked layers are important causes of the superior catalytic activity of the nanocomposites. Covalent linking of such 2D materials appears to be a worthwhile strategy for catalysis and other applications.
Pramoda et al. (Tue,) studied this question.