Rasool Faisal, Pirzada Bilal Masood, Talib Shamraiz Hussain, Alkhidir Tamador, Anjum Dalaver H, Mohamed Sharmarke, Qurashi Ahsanulhaq
Department of Chemistry, Khalifa University of Science and Technology, Abu Dhabi 127788, United Arab Emirates.
Center for Catalysis and Separations, Khalifa University of Science and Technology, Abu Dhabi, P.O. Box 127788, United Arab Emirates.
ACS Appl Mater Interfaces. 2024 Mar 20;16(11):14229-14242. doi: 10.1021/acsami.3c11642. Epub 2024 Mar 11.
In line with current research goals involving water splitting for hydrogen production, this work aims to develop a noble-metal-free electrocatalyst for a superior hydrogen evolution reaction (HER). A single-step interfacial activation of TiCT MXene layers was employed by uniformly growing embedded WS two-dimensional (2D) nanopetal-like sheets through a facile solvothermal method. We exploited the interactions between WS nanopetals and TiCT nanolayers to enhance HER performance. A much safer method was adopted to synthesize the base material, TiCT MXene, by etching its MAX phase through mild in situ HF formation. Consequently, WS nanopetals were grown between the MXene layers and on edges in a one-step solvothermal method, resulting in a 2D-2D nanocomposite with enhanced interactions between WS and TiCT MXene. The resulting 2D-2D nanocomposite was thoroughly characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman, Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) analyses before being utilized as working electrodes for HER application. Among various loadings of WS into MXene, the 5% WS-TiCT MXene sample exhibited the best activity toward HER, with a low overpotential value of 66.0 mV at a current density of -10 mA cm in a 1 M KOH electrolyte and a remarkable Tafel slope of 46.7 mV·dec. The intercalation of 2D WS nanopetals enhances active sites for hydrogen adsorption, promotes charge transfer, and helps attain an electrochemical stability of 50 h, boosting HER reduction potential. Furthermore, theoretical calculations confirmed that 2D-2D interactions between 1T/2H-WS and TiCT MXene realign the active centers for HER, thereby reducing the overpotential barrier.
与当前涉及水分解制氢的研究目标一致，本工作旨在开发一种用于高效析氢反应（HER）的无贵金属电催化剂。通过简便的溶剂热法均匀生长嵌入的二维（2D）纳米花瓣状WS片，对TiCT MXene层进行单步界面活化。我们利用WS纳米花瓣与TiCT纳米层之间的相互作用来提高HER性能。采用一种更安全的方法，通过温和的原位HF形成蚀刻其MAX相来合成基础材料TiCT MXene。因此，WS纳米花瓣通过一步溶剂热法生长在MXene层之间和边缘，形成了一种WS与TiCT MXene之间相互作用增强的2D-2D纳米复合材料。在将所得的2D-2D纳米复合材料用作HER应用的工作电极之前，使用X射线衍射（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、拉曼光谱、傅里叶变换红外（FTIR）光谱和X射线光电子能谱（XPS）分析对其进行了全面表征。在WS负载到MXene的各种比例中，5% WS-TiCT MXene样品对HER表现出最佳活性，在1 M KOH电解液中，电流密度为-10 mA cm时过电位低至66.0 mV，塔菲尔斜率为46.7 mV·dec。二维WS纳米花瓣的嵌入增加了氢吸附的活性位点，促进了电荷转移，并有助于实现50 h的电化学稳定性，提高了HER还原电位。此外，理论计算证实，1T/2H-WS与TiCT MXene之间的2D-2D相互作用重新排列了HER的活性中心，从而降低了过电位势垒。
