Bimetallic Co–Mo sulfide/carbon composites derived from polyoxometalate encapsulated polydopamine-decorated ZIF nanocubes for efficient hydrogen and oxygen evolution

Abstract

The increased call on carbon neutrality by 2050 makes it compelling to develop emission-free alternative energy sources. Green hydrogen produced from water electrolyzer by renewable electricity is of great importance,...

Hierarchical CoMoS3.13/MoS2hollow nanosheet arrays as bifunctional electrocatalysts for overall water splitting

“…5d), the characteristic peaks located at 162.2 and 163.3 eV can be assigned to S 2p 3/2 from Mo–S bonding and S 2p 1/2 from Co–S bonding, 58,59 and the peaks at 170.4 and 169.1 eV are indexed to S 2p 1/2 and S 2p 3/2 spin-orbitals from S–O bonds, which are partly due to an intermediate oxide formed during pyrolysis and partly due to the surface oxidation of the samples during XPS inspection. 50,60 Moreover, the intensity of S–O bond peak decreased significantly in the case of CMM 0.5, implying improved resistance to the oxidation of the heterostructured material. Because of the higher electronegativity of Mo (2.16) compared with Co (1.88), interfacial electrons are transferred from Co to Mo, which can reduce the number of unoccupied Mo d orbitals, 53 leading to higher Co and lower Mo valence.…”

MOF-Derived Multi-heterostructured Composites for Enhanced Photocatalytic Hydrogen Evolution: Deciphering the Roles of Different Components

“…Synthesis of NH 2 -MIL-125(Ti/Cu). As a second metal, Cu was loaded into NH 2 -MIL-125(Ti) via a postsynthesis modification method 24,25 rather than the conventional one-pot synthesis. 26 Typically, 2 g of dried NH 2 -MIL-125(Ti) was dispersed in 200 mL of MeOH and DMF and ultrasonicated for 3 h. A Cu(NO 3 ) 2 •3H 2 O (0.86 g) solution in MeOH (20 mL) was poured into the NH 2 -MIL-125(Ti) dispersion followed by heating at 110 °C for 12 h. The darkgreen powder of Cu-loaded NH 2 -MIL-125(Ti/Cu) was centrifuged and washed multiple times in MeOH for complete removal of unreacted Cu species followed by drying in a vacuum oven at 80 °C.…”

Transformation mechanism of high-valence metal sites for the optimization of Co- and Ni-based OER catalysts in an alkaline environment: recent progress and perspectives

“…Electrocatalysis not only could achieve efficient energy conversion, but also could transform some low-value resources into useful chemical products. 19–24 As important half-reactions, OERs are often overlooked by laymen because they do not yield useful chemical products such as H 2 , NH 3 , and CO. In fact, OERs provided protons and electrons in the overall catalytic system, which was related to the overall efficiency of the electrochemical reaction.…”