Ruthenium decorated 2D N-doped carbon nanocone arrays for pH-universal electrocatalytic hydrogen evolution

Abstract

The development of efficient and durable electrocatalysts for hydrogen evolution reaction (HER) is crucial for sustainable electrochemical water splitting and its practical application. However, the inappropriate binding with H* and sluggish reaction kinetics limit their overall HER performance, especially in alkaline electrolyte. Herein, we report a robust and high active HER electrocatalyst with optimized metal-H* interaction and low water dissociation energy barrier through interatomic d-p orbital hybridization. The Ru nanoparticles with mean size down to 1.7 nm are anchored on two-dimension nitrogen-doped carbon nanocone arrays via a facile aqueous-organic interfacial method. This unique architecture induces strong interaction between Ru and the carbon support. Electrons are transferred from Ru to the N-doped carbon, causing a shift of charge distribution and modified surface properties of Ru. Furthermore, the newly emerged Ru-N bonds endow the catalyst with high structure robustness. As a result, the catalyst exhibits superior HER performances in both alkaline and acidic electrolytes, with low overpotentials (31 and 29 mV at 10 mA cm−2 respectively), high H2 turn over frequency (2.20 s−1 at the overpotential of 25 mV) and excellent durability (10,000 cycles). The density functional theory calculations reveal that the boosted HER activity can be attributed to the downshift of the d-band center of Ru, which lowers the |ΔG(H*)| and accelerates the H-OH cleavage.