Novel Strain Engineering Combined with a Microscopic Pore Synergistic Modulated Strategy for Designing Lattice Tensile-Strained Porous V₂C-MXene for High-Performance Overall Water Splitting

Abstract

Transition metal carbon/nitride (MXene) holds immense potential as an innovative electrocatalyst for enhancing the overall water splitting properties. Nevertheless, the re-stacking nature induced by van der Waals force remains a significant challenge. In this work, the lattice tensile-strained porous V 2 C-MXene (named as TS (24) -P (50) -V 2 C) is successfully constructed via the rapid spray freezing method and the following hydrothermal treatment. Besides, the influence of lattice strain degree and microscopic pores on the catalytic ability is reviewed and explored systematically. The lattice tensile strain within V 2 C-MXene could widen the interlayer spacing and accelerate the ion transfer. The microscopic pores could change the ion transmission path and shorten the migration distance. As a consequence, the obtained TS (24) -P (50) -V 2 C shows extraordinary hydrogen evolution reaction and oxygen evolution reaction activity with the overpotential of 154 and 269 mV, respectively, at the current density of 10 mA/cm 2 , which is quite remarkable compared to the MXene-based electrocatalysts. Moreover, the overall water splitting device assembled using TS (24) -P (50) -V 2 C as both anode and cathode demonstrates a low cell voltage requirement of 1.57 V to obtain 10 mA/cm 2 . Overall, the implementation of this work could offer an exciting avenue to overcome the re-stacking issue of V 2 C-MXene, affording a highefficiency electrocatalyst with superior catalytic activity and desirable reaction kinetics.

Combustion Growth of NiFe Layered Double Hydroxide for Efficient and Durable Oxygen Evolution Reaction

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Oxygen defect engineering on low-crystalline iron(iii) oxyhydroxide as a highly efficient electrocatalyst for water oxidation

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In situ self-reconstructed hierarchical bimetallic oxyhydroxide nanosheets of metallic sulfides for high-efficiency electrochemical water splitting

“…S19, ESI†), it is found that the lattice has an obvious tensile distortion. 55 This distortion may be due to the synergistic effect between the two metals, which changes the corresponding coordination environment, and results in lattice distortion. The results presented here fully prove the formation of low crystalline FeCoOOH.…”