1D/3D rambutan-like Mott–Schottky porous carbon polyhedrons for efficient tri-iodide reduction and hydrogen evolution reaction

Abstract

Realizing rapid electron transfer and mass diffusion in virtue of interface regulation and nanostructure design is an effective strategy to augment the catalytic activity of carbon materials but still a significant challenge. Herein, a novel frontier 1D/3D rambutan-like Mott-Schottky-type nitrogen-doped carbon polyhedron (NiCo-NCP/CNT) consisting of nickel/cobalt species and a 3D porous carbon skeleton intertwined with 1D carbon nanotubes (CNT) is controllably fabricated by rationally utilizing Co/Zn bimetallic-organic frameworks and nickel ions. The photovoltaic device fabricated with NiCo-NCP/CNT electrocatalyst achieves a power conversion efficiency of 8.75%, which is superior to that of conventional Pt electrodes (7.25%). When the NiCo-NCP/CNT electrocatalyst is employed as the cathode for water splitting under alkaline conditions, an overpotential as low as 63 mV is demonstrated at a current density of 10 mA·cm−2. The improved work function (from 4.65 to 4.59 eV) proves that introducing NiCo favors regulating electronic states and optimizing energy level, which could induce more robust self-driven electron transfer at the Mott-Schottky interface. The proposed nickel adsorption-sintering strategy effectively promotes electron/mass transfer capability simultaneously in carbon-based Mott-Schottky catalysts and paves the way for developing low-cost and high-performance electrocatalysts in electrocatalytic fields.