Self-supporting multi-channel Janus carbon fibers: A new strategy to achieve an efficient bifunctional...

A new type of self-supporting multi-channel Janus carbon fibers with efficient water splitting has been successfully manufactured using a specially designed parallel spinneret through electrospinning technology and subsequent carbonization technique. Every single Janus fiber composes of a half side of Mo₂C and the other half side of Ni components as Mo₂C, Ni embedded in N-doped multi-channel Janus carbon fibers ([Mo₂C/C]//[Ni/C]-NMCFs) for overall water splitting. Under optimized condition, the hydrogen evolution reaction overpotential of [Mo₂C/C]//[Ni/C]-NMCFs (62 mV) is just 24 mV higher than 20 wt% Pt/C (38 mV) at a current density of 10 mA cm^-2. Furthermore, it achieves current density of 10 mA cm^-2 to require an overpotential of 324 mV for oxygen evolution reaction. Additionally, the cell assembled by the identical [Mo₂C/C]//[Ni/C]-NMCFs catalyst as both the cathode and anode needs only 1.607 V at a current density of 10 mA cm^-2, which is only 0.022 V higher than that of Pt/C-IrO₂ electrodes. Moreover, [Mo₂C/C]//[Ni/C]-NMCFs catalyst also exhibits a long-term stability. The synergistic effect and unique heterostructure of Mo₂C and Ni enhance the catalytic activity.