Basal Plane Hydrogen Evolution Activity from Mixed Metal Nitride MXenes Measured by Scanning Electrochemical Microscopy
Basal Plane Hydrogen Evolution Activity from Mixed Metal Nitride MXenes Measured by Scanning Electrochemical Microscopy
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DOI：
10.1002/adfm.202001136
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发表时间：
2020-05-19
影响因子：
19
通讯作者：
Neale, Nathan R.
中科院分区：
文献类型：
--
作者：
Djire, Abdoulaye;Wang, Xiang;Neale, Nathan R.
2D前过渡金属碳化物和氮化物MXene具有有趣的电化学储能和电催化性能。这些性质可以通过修改基面化学来操纵。这里，混合过渡金属氮化物MXene，M-Ti4 N3 Tx（M = V、Cr、Mo或Mn; T-x = O和/或OH），通过使用简单的基于溶液的方法用V、Cr、Mo和Mn盐改性原始剥离的Ti4 N3 Tx MXene而开发。所得的混合过渡金属氮化物MXene含有6-51%的金属负载（参见图1）。Ti），其表现出丰富的电化学，包括如下在0.5mM H2SO 4电解质中高度可调的析氢反应（HER）电催化活性：V-Ti4 N3 Tx> Cr-Ti4 N3 Tx> Mo-Ti4 N3 Tx> Mn-Ti4 N3 Tx>原始Ti4 N3 Tx，在-10mA cm（-2）下具有低至330 mV的过电位，电荷转移电阻为70 Ω。扫描电化学显微镜（SECM）揭示了单个MXene薄片的电化学活性。SECM数据证实了M-Ti4 N3 Tx的整体HER活性趋势，并提供了HER由MXene基面上的催化产生的第一个实验证据。这些电催化结果表明了一种新的途径来调整MXene的电化学性质，用于水裂解和相关的电化学应用。
2D early transition metal carbide and nitride MXenes have intriguing properties for electrochemical energy storage and electrocatalysis. These properties can be manipulated by modifying the basal plane chemistry. Here, mixed transition metal nitride MXenes, M-Ti4N3Tx (M = V, Cr, Mo, or Mn; T-x = O and/or OH), are developed by modifying pristine exfoliated Ti4N3Tx MXene with V, Cr, Mo, and Mn salts using a simple solution-based method. The resulting mixed transition metal nitride MXenes contain 6-51% metal loading (cf. Ti) that exhibit rich electrochemistry including highly tunable hydrogen evolution reaction (HER) electrocatalytic activity in a 0.5 m H2SO4 electrolyte as follows: V-Ti4N3Tx > Cr-Ti4N3Tx > Mo-Ti4N3Tx > Mn-Ti4N3Tx > pristine Ti4N3Tx with overpotentials as low as 330 mV at -10 mA cm(-2) with a charge-transfer resistance of 70 omega. Scanning electrochemical microscopy (SECM) reveals the electrochemical activity of individual MXene flakes. The SECM data corroborate the bulk HER activity trend for M-Ti4N3Tx as well as provide the first experimental evidence that HER results from catalysis on the MXene basal plane. These electrocatalytic results demonstrate a new pathway to tune the electrochemical properties of MXenes for water splitting and related electrochemical applications.