Niu Hua-Jie, Yan Yu, Jiang SiSi, Liu Tong, Sun Tong, Zhou Wei, Guo Lin, Li Jinghong
School of Chemistry, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, China.
College of Chemistry and Chemical Engineering, Instrumental Analysis Center of Qingdao University, Qingdao University, Qingdao 266071, China.
ACS Nano. 2022 Jul 26;16(7):11049-11058. doi: 10.1021/acsnano.2c03711. Epub 2022 Jul 7.
Heterointerfaces can adjust the adsorption energy with intermediates in the transition state for a much decreased kinetics energy barrier (). One typical transition metal phosphide, NiCoP grains (∼5 nm in size), was anchored on a TiCT MXene monolayer (∼1 nm in thickness) to boost the kinetics toward alkaline hydrogen evolution reaction (HER). General electrochemical experiments at different temperatures give a small of 31.4 kJ mol, showing a 22.1% decrease compared to its counterpart NiCoP nanoparticles (40.3 kJ mol). Impressively, the overpotential of NiCoP@MXene dramatically decreases from 71 mV to 4 mV at 10 mA cm when the temperature increases from 25 °C to 65 °C. On a single NiCoP@MXene sheet, scanning electrochemical microscopy (SECM) tests also give a very close value of = 31.9 kJ mol, with a relative error of ∼1.6%. Density functional theory (DFT) calculations confirm the interface between NiCoP and MXene can effectively decrease the energy barrier of water dissociation by 16.0%. The three kinds of studies on macro, micro/nano, and atomic scales disclose the interfaces can reduce the kinetics energy barrier about 16.0-22.1%. Besides, the photothermal effect of MXenes can easily raise the catalyst temperature under vis-NIR light, which has been applied in practical scenarios under sunlight for energy savings.
异质界面可以调节与过渡态中间体的吸附能，从而大幅降低动力学能垒（）。一种典型的过渡金属磷化物，即尺寸约为5纳米的NiCoP颗粒，被锚定在厚度约为1纳米的TiCT MXene单层上，以加快碱性析氢反应（HER）的动力学。在不同温度下进行的一般电化学实验得出的活化能较小，为31.4 kJ/mol，与其对应的NiCoP纳米颗粒（40.3 kJ/mol）相比降低了22.1%。令人印象深刻的是，当温度从25℃升高到65℃时，NiCoP@MXene的过电位在10 mA/cm²时从71 mV急剧降至4 mV。在单个NiCoP@MXene片材上，扫描电化学显微镜（SECM）测试也得出了非常接近的活化能值，为31.9 kJ/mol，相对误差约为1.6%。密度泛函理论（DFT）计算证实，NiCoP与MXene之间的界面可以有效地将水分解的能垒降低16.0%。在宏观、微观/纳米和原子尺度上的这三种研究表明，界面可以将动力学能垒降低约16.0 - 22.1%。此外，MXene的光热效应可以在可见光-近红外光下轻松提高催化剂温度，这已在阳光照射下的实际场景中得到应用以实现节能。
