纳米片
密度泛函理论
过电位
单层
材料科学
结晶学
结构精修
催化作用
六角相
拉曼光谱
相(物质)
吉布斯自由能
过渡金属
纳米技术
晶体结构
物理化学
计算化学
化学
六方晶系
热力学
电化学
物理
生物化学
有机化学
电极
光学
作者
Anup Debnath,Nabanita Sen,Arnab Das,Souvik Bhattacharjee,Suman Dey,Biswarup Satpati,Kalyan Kumar Chattopadhyay
摘要
Researchers are increasingly drawn to WSe2 due to its wide-ranging applications in electronic, optoelectronic, and catalytic materials. Like other transition metal dichalcogenides, it has different polymorphs, viz., 1T, 1T′, and 2H phases. A hexagonal close-packed layer-type structure of 2H-WSe2 is well studied and possesses a semiconducting behavior. However, the literature lacks a detailed study of crystallographic structure, facile synthesis, and different physical properties of 1T′-WSe2 (or 1T-phase). In this article, we synthesized a stable flower-like 1T′-WSe2 nanosheet in a facile solvothermal process. We also tried to explore the structural details using the Rietveld refinement of the powder x-ray diffraction data. The different Raman vibrational modes and phonon calculation based on the density functional theory (DFT) were performed to understand the stability of the 1T′-WSe2 phase. The flower-like 1T′-WSe2 nanosheet shows better catalytic activity for the hydrogen evolution reaction (HER) with an onset potential of −0.21 mV and overpotential 0.47 mV in comparison with the 2H-phase of WSe2 nanosheet. The DFT calculations also support the experimental data on the HER of 1T′-WSe2, establishing the suitability of the 1T′-phase for HER activity with the lowest value of the change in Gibbs free energy of hydrogen adsorption, ΔGH = 0.43 eV, for the monolayer.
科研通智能强力驱动
Strongly Powered by AbleSci AI