Chapter 3A Advances in understanding electrochemical reaction mechanisms of highly dispersed metal sites using X-ray absorption spectroscopy
-
Hao Zhang
Abstract
During the past decade, highly dispersed metal sites (HDMSs) have attracted considerable attention in electrocatalysis because of their intriguing catalytic performance and maximum efficiency of atomic utilization. These sites usually appear in single/ dual-atom catalysts or subnanometric clusters, whose long-range structures are disordered and catalytic performances are intimately correlated with coordination environments and interactions with support. When applied in reaction, these unsaturated coordination sites within HDMSs strongly interact with the environment (support, electrolyte, ligands, adsorbates, reaction products, and intermediates), leading their structures to change with the reaction conditions. In this regard, clarifying the actual structure of HDMSs is of great importance for understanding the reaction mechanism and for further catalytic optimization. X-ray absorption spectroscopy (XAS) is an indispensable technique for probing the electronic and geometric structures of HDMSs. This chapter discusses the fundamental principles of the XAS method, introduces the experimental paradigm of data collection in the transmission and fluorescence models, and describes the data analysis approaches undertaken for deciphering X-ray absorption near the edge and extended X-ray absorption fine structure spectra. Moreover, we will illustrate the XAS studies of highly dispersed metal catalysts in a wide range of electrochemical reactions and highlight the application of in situ and operando XAS for revealing the nature of the active sites and establishing links between the structural motifs in HDMSs, local electronic structures, and catalytic properties.
Abstract
During the past decade, highly dispersed metal sites (HDMSs) have attracted considerable attention in electrocatalysis because of their intriguing catalytic performance and maximum efficiency of atomic utilization. These sites usually appear in single/ dual-atom catalysts or subnanometric clusters, whose long-range structures are disordered and catalytic performances are intimately correlated with coordination environments and interactions with support. When applied in reaction, these unsaturated coordination sites within HDMSs strongly interact with the environment (support, electrolyte, ligands, adsorbates, reaction products, and intermediates), leading their structures to change with the reaction conditions. In this regard, clarifying the actual structure of HDMSs is of great importance for understanding the reaction mechanism and for further catalytic optimization. X-ray absorption spectroscopy (XAS) is an indispensable technique for probing the electronic and geometric structures of HDMSs. This chapter discusses the fundamental principles of the XAS method, introduces the experimental paradigm of data collection in the transmission and fluorescence models, and describes the data analysis approaches undertaken for deciphering X-ray absorption near the edge and extended X-ray absorption fine structure spectra. Moreover, we will illustrate the XAS studies of highly dispersed metal catalysts in a wide range of electrochemical reactions and highlight the application of in situ and operando XAS for revealing the nature of the active sites and establishing links between the structural motifs in HDMSs, local electronic structures, and catalytic properties.
Kapitel in diesem Buch
- Frontmatter I
- Contents V
- Common abbreviations VII
- Preface 1
-
Section 1: Overview of nanoscience and nanochemistry
- Chapter 1 Nanochemistry: development of nanomaterials 31
-
Section 2: Focus on synthesis methods
- Chapter 2A Wet-chemistry-derived nanomaterials and their multidisciplinary applications 131
- Chapter 2B Bottom-up synthesis of nanomaterials 239
- Chapter 2C Green pathways to synthesize nanomaterials 267
- Chapter 2D Synthesis and stabilization of metallic nanoparticles 307
-
Section 3: Focus on characterization methods
- Chapter 3A Advances in understanding electrochemical reaction mechanisms of highly dispersed metal sites using X-ray absorption spectroscopy 327
- Chapter 3B In situ spectroscopic studies of the electrochemistry 357
- Chapter 3C Integrated X-ray scattering and molecularscale simulation approaches to probe the behavior of confined fluids for a sustainable energy future 437
-
Section 4: Focus on select example applications of nanoscience in energy, environment, and health
- Chapter 4A Electrocatalytic hydrogen production 461
- Chapter 4B Nanostructured materials for electrocatalytic hydrogen evolution reaction 489
- Chapter 4C Recent progress in cobalt-based nanosheets for electrochemical water oxidation 537
- Chapter 4D Nanoapplication: carbon capture and conversions 565
- Postface: social impact, consequences, and results of nanotechnology 583
- Biography of the editors 593
- Biography of the authors 595
- Author list 603
- Index 607
Kapitel in diesem Buch
- Frontmatter I
- Contents V
- Common abbreviations VII
- Preface 1
-
Section 1: Overview of nanoscience and nanochemistry
- Chapter 1 Nanochemistry: development of nanomaterials 31
-
Section 2: Focus on synthesis methods
- Chapter 2A Wet-chemistry-derived nanomaterials and their multidisciplinary applications 131
- Chapter 2B Bottom-up synthesis of nanomaterials 239
- Chapter 2C Green pathways to synthesize nanomaterials 267
- Chapter 2D Synthesis and stabilization of metallic nanoparticles 307
-
Section 3: Focus on characterization methods
- Chapter 3A Advances in understanding electrochemical reaction mechanisms of highly dispersed metal sites using X-ray absorption spectroscopy 327
- Chapter 3B In situ spectroscopic studies of the electrochemistry 357
- Chapter 3C Integrated X-ray scattering and molecularscale simulation approaches to probe the behavior of confined fluids for a sustainable energy future 437
-
Section 4: Focus on select example applications of nanoscience in energy, environment, and health
- Chapter 4A Electrocatalytic hydrogen production 461
- Chapter 4B Nanostructured materials for electrocatalytic hydrogen evolution reaction 489
- Chapter 4C Recent progress in cobalt-based nanosheets for electrochemical water oxidation 537
- Chapter 4D Nanoapplication: carbon capture and conversions 565
- Postface: social impact, consequences, and results of nanotechnology 583
- Biography of the editors 593
- Biography of the authors 595
- Author list 603
- Index 607
