Self-Supporting Hierarchical Carbon Network Loaded with NiW Nanoparticles for Efficient Hydrogen Evolution.

ABSTRACT

Water splitting technology can convert renewable energies such as solar and wind into hydrogen energy, which is key to achieving a low-carbon hydrogen economy cycle. However, Pt-based catalysts for hydrogen evolution reaction (HER) are too expensive, thus it needs to develop efficient non-noble metal catalysts as alternatives. Herein, Ni-BDC-loaded carbon cloth (CC) is co-pyrolyzed with urea to obtain a composite structure of carbon nanotubes (CNT) and porous carbon (PC) embedded with W-doped Ni nanoparticles on CC, resulting in NiW-CNT/PC/CC. Benefiting from the synergistic effect between Ni and W, the high conductivity of CNT, and the high mass transfer rate of PC, NiW-CNT/PC/CC exhibits excellent HER activity in KOH, which only requires a low overpotential of 45 mV to drive a current density of 10 mA cm-2 with stability exceeding 40 h. Simulation calculations confirm that the W doping in metal Ni can optimize its electronic structure by lowering the d-band center and weakening hydrogen adsorption, thus reducing its HER barrier.