An Efficient H2S‑Tolerant Hydrogen Oxidation Electrocatalyst Enabled by a Lewis Acid Modifier for Fuel Cells
An Efficient H2S‑Tolerant Hydrogen Oxidation Electrocatalyst Enabled by a Lewis Acid Modifier for Fuel Cells
研究概述
研究内容请参见论文原文。
谱图与表征信息
Figure 2. Electronic structure and surface analysis. (a) Ni K-edge XANES spectra of MoNi4@C and Cr2O3-MoNi4@C with Ni foil and NiO as references. Inset shows the zoomed-in view of the white lines for the samples. (b) Fourier transforms of k3-weighted EXAFS spectra at the Ni K- edge. (c) The average coordination numbers (CN) in the first coordination shell of Ni atoms for Ni foil, MoNi4@C, and Cr2O3-MoNi4@C by EXAFS curve fitting. The CN of Ni foil is 12. (d−f) Corresponding WT of k3-weighted EXAFS spectra of the Ni K-edge for Ni foil (d), MoNi4@C (e), and Cr2O3-MoNi4@C (f). (g) PZC measurements by the Gouy−Chapman capacitance minimum method for MoNi4@C and Cr2O3-MoNi4@ C. (h) UPS spectra of MoNi4@C and Cr2O3-MoNi4@C. (i) Zeta potentials of Cr2O3, MoNi4@C, and Cr2O3-MoNi4@C.
Figure 4. Spectroscopic investigation. (a) In situ Raman spectroscopy recorded at 0.1 V in H2-saturated 0.1 M KOH with and without S2−for Pt/ C, MoNi4@C, and Cr2O3-MoNi4@C catalysts. (b, c) In situ Raman spectroscopy recorded by stepping the potential from 0 to 0.2 V in H2- saturated 0.1 M KOH for MoNi4@C (b) and Cr2O3-MoNi4@C (c) catalysts. (d) Fourier transformations of k3-weighted EXAFS spectra of Cr2O3- MoNi4@C at the Cr K-edge during HOR at different applied potentials. (e) Measurement of pH values on MoNi4@C and Cr2O3-MoNi4@C surfaces at HOR bias in NaClO4 solution (pH = 10) using an IrOx-modified RRDE method (schematic shown as an inset). (f) Potential-dependent proportion of H2O(gap) molecules in the EDL of the MoNi4@C and Cr2O3-MoNi4@C catalysts. Error bars in (f) represent the standard deviation determined based on three individual measurements.