Interface modulation induced by the 1T Co-WS2 shell nanosheet layer at the metallic NiTe2/Ni core–nanoskeleton: Glib electrode-kinetics for HER, OER, and ORR.

The metallic (1T) transition metal dichalcogenides (TMDCs) are known for their superior electrocatalytic performance, due to their high conductivity, active basal-planes, and exposed edges. Our novel approach of coupling a metallic-NiTe 2 /Ni nano-skeleton with 1T-Co-WS 2 nanosheet in a core–shell arrangement to develop a hybrid heterostructure (1T Co-WS 2 /NiTe 2 /Ni) has helped to outperform the trifunctional-electrocatalytic activity (HER, OER, and ORR). 1T-Co-WS 2 /NiTe 2 /Ni only requires ultralow overpotential (η HER = 88 mV@10, η OER = 290 mV@30), higher half-wave potential for ORR (E 1/2 = 0.781 V vs RHE), small Tafel slopes (HER = 68 mV dec^-1, OER = 98 mV dec^-1, and ORR = 63 mV dec^-1) with high electrocatalytic surface area and robust stability in corresponding half-cell reactions. The designed heterostructured electrocatalyst (1T Co-WS 2 /NiTe 2 /Ni) presented exceptional total water-splitting performance, requiring a low voltage of 1.521 V to yield 10 mA cm⁻² current with extensive structural and electrochemical durability. Such performance could be attributed towards improved nanochannel morphology with exposed active edge, fluent electrode-kinetics, facile adsorption–desorption of reaction intermediates owing to the intrinsically tuned 1T-WS 2 by cobalt-doping, and hybridized NiTe 2 /Ni nano-skeleton. The DFT study confirmed that the incorporation of Co atoms in basal plane and the edge sites of WS 2 lattice induces the redistribution and modulation of electronic structure for fast electron/charge transfer and the synergistic coupling of 1T NiTe 2 heterostructures bolstered the electrocatalytic activity of the as-prepared catalysts. These outcomes provide a prospect towards the design and application of efficient 2D/2D heterostructured electrocatalyst for zero emission energy goal. [Display omitted] • Developed multifunctional 1T Co-WS 2 shell-nanochannels layer at the metallic NiTe 2 /Ni core–nanoskeleton sheet electrocatalyst by facile hydrothermal strategy. • Staggering HER/OER/ORR catalytic efficacy of 1T-Co-WS 2 /NiTe 2 /Ni is observed with only η HER of 88 mV @ 10 mA cm^-2, η OER of 290 mV @ 30 mA cm^-2 and E 1/2 of 0.781 for ORR. • Superior overall water-splitting performance of 1T-Co-WS 2 /NiTe 2 /Ni(+,−) alkaline electrolyzer, required cell potential of 1.521 V at 10 mA cm⁻². • DFT reveals the redistribution and modulation of electronic structure and synergistic coupling of the heterostructures. [ABSTRACT FROM AUTHOR]