Scholarlink

<p>Two-dimensional (2D) transition metal carbides, nitrides and carbonitrides, known as MXenes, are of interest as electrocatalysts. Tungsten-based MXenes are predicted to have low overpotentials in the hydrogen evolution reaction but their synthesis has proven difficult due to the calculated instability of their hypothetical MAX precursors. In this study, we present a theory-guided synthesis of a tungsten-based MXene, W<sub>2</sub>TiC<sub>2</sub>T<sub><i>x</i></sub>, derived from a non-MAX nanolaminated ternary carbide (W,Ti)<sub>4</sub>C<sub>4−<i>y</i></sub> precursor by the selective etching of one of the covalently bonded tungsten layers. Our results indicate the importance of tungsten and titanium ordering, the presence of vacancy defects in the metal layers, and the lack of oxygen impurities in the carbon layers for the successful selective etching of the precursor. We confirm the atomistic out-of-plane ordering of tungsten and titanium using computational and experimental characterizations. The tungsten-rich basal plane endows W<sub>2</sub>TiC<sub>2</sub>T<sub><i>x</i></sub> MXene with a high electrocatalytic hydrogen evolution reaction performance (∼144 mV overpotential at 10 mA cm<sup>−</sup><sup>2</sup>). This study reports a tungsten-based MXene synthesized from a covalently bonded non-MAX precursor, adding to the synthetic strategies for 2D materials.</p><p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Synthesis of a 2D tungsten MXene for electrocatalysis

  • 期刊论文

  • 发表日期：

    2025年3月28日

查看全文
  • Anupma Thakur,
  • Wyatt J. Highland,
  • Brian C. Wyatt,
  • Jiayi Xu,
  • Nithin Chandran B. S,
  • Bowen Zhang,
  • Zachary D. Hood,
  • Shiba P. Adhikari,
  • Emad Oveisi,
  • Barbara Pacakova,
  • Fernando Vega,
  • Jeffrey Simon,
  • Colton Fruhling,
  • Benjamin Reigle,
  • Mohammad Asadi,
  • Pawel P. Michałowski,
  • Vladimir M. Shalaev,
  • Alexandra Boltasseva,
  • Thomas E. Beechem,
  • Cong Liu,
  • Babak Anasori

摘要

Two-dimensional (2D) transition metal carbides, nitrides and carbonitrides, known as MXenes, are of interest as electrocatalysts. Tungsten-based MXenes are predicted to have low overpotentials in the hydrogen evolution reaction but their synthesis has proven difficult due to the calculated instability of their hypothetical MAX precursors. In this study, we present a theory-guided synthesis of a tungsten-based MXene, W2TiC2Tx, derived from a non-MAX nanolaminated ternary carbide (W,Ti)4C4−y precursor by the selective etching of one of the covalently bonded tungsten layers. Our results indicate the importance of tungsten and titanium ordering, the presence of vacancy defects in the metal layers, and the lack of oxygen impurities in the carbon layers for the successful selective etching of the precursor. We confirm the atomistic out-of-plane ordering of tungsten and titanium using computational and experimental characterizations. The tungsten-rich basal plane endows W2TiC2Tx MXene with a high electrocatalytic hydrogen evolution reaction performance (∼144 mV overpotential at 10 mA cm−2). This study reports a tungsten-based MXene synthesized from a covalently bonded non-MAX precursor, adding to the synthetic strategies for 2D materials.