Nitrogen-doped Nanoporous Carbon Membranes Functionalized with Co/CoP Janus-type nanocrystals as Hydrogen Evolution Electrode in Both Acid and Alkaline Environment

TL;DR

This paper presents a novel nitrogen-doped nanoporous carbon membrane functionalized with Janus Co/CoP nanocrystals, serving as an efficient, stable, and binder-free electrode for hydrogen evolution in both acidic and alkaline environments, with practical demonstration under solar-driven water electroreduction.

Contribution

The study introduces a new synthesis method for freestanding, hierarchically structured carbon membranes with Janus Co/CoP nanocrystals, enhancing HER performance and stability in diverse pH conditions.

Findings

High electrocatalytic activity for HER in acid and alkaline media

Long-term stability of the electrode during operation

Successful demonstration of solar-driven water electroreduction producing hydrogen

Abstract

Self-supported electrocatalysts being generated and employed directly as electrode for energy conversion has been intensively pursued in the fields of materials chemistry and energy. Herein, we report a synthetic strategy to prepare freestanding hierarchically structured, nitrogen-doped nanoporous graphitic carbon membranes functionalized with Janus-type Co/CoP nanocrystals (termed as HNDCM-Co/CoP), which were successfully applied as a highly-efficient, binder-free electrode in hydrogen evolution reaction (HER). Benefited from multiple structural merits, such as high degree of graphitization, three-dimensionally interconnected micro-/meso-/macropores, uniform nitrogen-doping, well-dispersed Co/CoP nanocrystals as well as the confinement effect of the thin carbon layer on the nanocrystals, HNDCM-Co/CoP exhibited superior electrocatalytic activity and long-term operation stability for HER under both acid and alkaline conditions. As a proof-of-concept of practical usage, a macroscopic piece of HNDCM-Co/CoP of 5.6 cm x 4 cm x 60 um in size was prepared in our laboratory. Driven by a solar cell, electroreduction of water in alkaline condition (pH 14) was performed, and H2 has been produced at a rate of 16 ml/min, demonstrating its potential as real-life energy conversion systems.