Rapid Electronic Transport Channel of Co-P with Mo in a Heterostructure Embedded with P, N Dual Doped Porous Carbon for Electrocatalytic Oxygen and Hydrogen Evolution

We developed a molybdenum (Mo)-doped cobalt (Co)-heterostructure embedded on a phosphorous (P) and nitrogen (N) dual-doped porous carbon which exhibits an intrinsic electronic transport channel of Co to Mo and P. The P,Mo,O−Co/PNC/NF (NF=Nickel foam) electrode offers 335 mV overpotential at 10 mA cm⁻² in OER as compared with PMA-ZIF67-NC/NF and ZIF67-NC/NF electrode with an overpotential of 357 and 373 mV respectively. Linear sweep voltammetry (LSV) of overall water splitting (OWS) supports that the current density gradually increased at a cell potential of 1.6 V with a maximum of 40 mA with a corresponding cell potential of 1.79 V at a current density of 10 mA cm⁻². Density functional theory (DFT) calculations for water adsorption on optimized [111] surface of Co, CoMo, and CoMoP₂ with adsorbed H₂O and corresponding lattice determine the electron density difference of [111] surface with adsorbed H₂O for E_ads (eV) 4.23 corresponds to adsorption energy for CoMoP₂. XANE-EXAFS spectroscopy of P,Mo,O−Co/PNC at Co K edge and Mo K edge suggests the presence of higher valence of both Co^x+ and Mo^x+ without metallic Co and Mo and Co−P and Mo−P bonds as major structural units due to phosphidation as determined by R-space FT-EXAFS spectra.