Catalysis of Alloys: Classification, Principles, and Design for a Variety of Materials and Reactions

Abstract

Alloying has long been used as a promising methodology to improve the catalytic performance of metallic materials. In recent years, the field of alloy catalysis has made remarkable progress with the emergence of a variety of novel alloy materials and their functions. Therefore, a comprehensive disciplinary framework for catalytic chemistry of alloys that provides a cross-sectional understanding of the broad research field is in high demand. In this review, we provide a comprehensive classification of various alloy materials based on metallurgy, thermodynamics, and inorganic chemistry and summarize the roles of alloying in catalysis and its principles with a brief introduction of the historical background of this research field. Furthermore, we explain how each type of alloy can be used as a catalyst material and how to design a functional catalyst for the target reaction by introducing representative case studies. This review includes two approaches, namely, from materials and reactions, to provide a better understanding of the catalytic chemistry of alloys. Our review offers a perspective on this research field and can be used encyclopedically according to the readers' individual interests. CONTENTS

Active site tuning based on pseudo-binary alloys for low-temperature acetylene semihydrogenation

“…For the vinyl on the hollow, the coordinating carbon atom was off-centered to be slightly far from the Cu atom, resulting in a "2.5-fold-like" state and signi cant destabilization. This trend indicated that the ensemble effect by Cu e ciently tuned the adsorptivity 24 . Moreover, the minute energy change for the on-top adsorption on Ni suggested that the contribution of the ligand effect of Cu on Ni was extremely minor.…”

Recent progress on the synthesis of metal alloy nanowires as electrocatalysts

“…25,32 One major benefit of forming an alloy is to provide adjustment of the surface electronic structures of the catalysts, leading to optimized binding between the catalyst surfaces and key intermediates of the electrocatalytic reactions. [35][36][37][38] For example, metals have different adsorption energies towards the *OH species, which is the key intermediate during oxygen reduction reactions (ORRs). 36,39 And although Pt and Pd are the best ORR catalyst candidates, the adsorption energies of *OH on these metals are still not optimized according to the volcano plot.…”

Durable Electrocatalytic CO2 Reduction Using Intermetallic Compound PdIn Nanoparticles and Their Application to a Solar Energy Harvesting System

“…Intermetallic compounds (IMCs), some of the binary alloys, have well-ordered atom arrangements in their crystal structures, being recognized as standout electrochemical , and thermal catalysts − for various reactions. This is because their surface atom arrangements are expected to be regular in each of their facets corresponding to Miller indices, which originates from their well-ordered crystal structures.…”