Raciti David, Schwarz Kathleen A, Vinson John, Stafford Gery R
Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States.
J Phys Chem C Nanomater Interfaces. 2022 Mar;126(9). doi: 10.1021/acs.jpcc.2c00134.
The change in surface stress associated with the adsorption and oxidative stripping of carbon monoxide (CO) on (111)-textured Pt is examined using the wafer curvature method in 0.1 mol/L KHCO electrolyte. The curvature of the Pt cantilever electrode was monitored as a function of potential in both CO-free and CO-saturated electrolytes. Although CO adsorbs as a neutral molecule, significant compressive stress, up to -1.3 N/m, is induced in the Pt. The magnitude of the stress change correlates directly with the CO coverage and, within the detection limits of the stress measurement, is elastically reversible. Density functional theory calculations of a CO-bound Pt surface indicate that charge redistribution from the first atomic layer of Pt to subsurface layers accounts for the observed compressive stress induced by the charge neutral adsorption of CO. A better understanding of adsorbate-induced surface stress is critical for the development of material platforms for sensing and catalysis.
采用晶圆曲率法在0.1mol/L KHCO电解质中研究了与一氧化碳（CO）在（111）织构Pt上的吸附和氧化脱附相关的表面应力变化。在无CO和CO饱和的电解质中，监测Pt悬臂电极的曲率随电位的变化。尽管CO作为中性分子吸附，但在Pt中会产生高达-1.3N/m的显著压应力。应力变化的幅度与CO覆盖率直接相关，并且在应力测量的检测限内是弹性可逆的。对CO吸附的Pt表面进行的密度泛函理论计算表明，从Pt的第一原子层到次表面层的电荷重新分布是由CO的电荷中性吸附引起的观察到的压应力的原因。更好地理解吸附质诱导的表面应力对于传感和催化材料平台的开发至关重要。
