Defect engineering in transition‐metal (Fe, Co, and Ni)‐based electrocatalysts for water splitting

Abstract

Electrocatalytic water splitting seems to be an efficient strategy to deal with increasingly serious environmental problems and energy crises but still suffers from the lack of stable and efficient electrocatalysts. Designing practical electrocatalysts by introducing defect engineering, such as hybrid structure, surface vacancies, functional modification, and structural distortions, is proven to be a dependable solution for fabricating electrocatalysts with high catalytic activities, robust stability, and good practicability. This review is an overview of some relevant reports about the effects of defect engineering on the electrocatalytic water splitting performance of electrocatalysts. In detail, the types of defects, the preparation and characterization methods, and catalytic performances of electrocatalysts are presented, emphasizing the effects of the introduced defects on the electronic structures of electrocatalysts and the optimization of the intermediates' adsorption energy throughout the review. Finally, the existing challenges and personal perspectives of possible strategies for enhancing the catalytic performances of electrocatalysts are proposed. An in‐depth understanding of the effects of defect engineering on the catalytic performance of electrocatalysts will light the way to design high‐efficiency electrocatalysts for water splitting and other possible applications.

Trimetallic FeNiMo Nanofibers as High-Efficiency Electrocatalyst for Robust Oxygen Evolution

“…Nowadays, there is an urgent need for environmentally friendly energy to meet the rapidly growing energy demand and alleviate environmental pollution. − Dihydrogen (H 2 ) is known for its pollution-free, zero-carbon emission, high efficiency, and large energy density; therefore, it is a prime candidate for the renewable energy transition. − Water electrolysis for generating H 2 is drawing widespread interest due to its efficient and economical H 2 generation with no pollution. − Notably, the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are the two processes in the overall water splitting, while the sluggish anodic OER process is the bottleneck. − Thus, developing novel electrocatalysts that improve the efficiency of the OER process is imperative. Unfortunately, the utilization of conventional noble-metal based OER catalysts, including Ir- and Ru-based materials, is limited due to their scarcity, expense and instability. − Transition metal-based compounds, such as metals/alloys, − layered double hydroxides, − oxides, − sulfides, − phosphates, − nitrides, − and selenides, − which possess abundant reserves, economy, and high activity, have garnered significant attention in recent years.…”