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Phase engineering is a critical strategy in electrocatalysis, as it allows for the modulation of electronic, geometric, and chemical properties to directly influence the catalytic performance. Despite its potential, phase engineering remains particularly challenging in thermodynamically stable perovskites, especially in a 2D structure constraint. Herein, we report phase engineering in 2D LaNiO3 perovskite using the strongly non‐equilibrium microwave shock method. This approach enables the synthesis of conventional hexagonal and unconventional trigonal and cubic phases in LaNiO3 by inducing selective phase transitions at designed temperatures, followed by rapid quenching to allow precise phase control while preserving the 2D porous structure. These phase transitions induce structural distortions in the [LaO]+ layers and the hybridization between Ni 3d and O 2p states, modifying local charge distribution and enhancing electron transport during the six‐electron urea oxidation process (UOR). The cubic LaNiO3 offers optimal electron transport and active site accessibility due to its high structural symmetry and open interlayer spacing, resulting in a low onset potential of 1.27 V and a Tafel slope of 33.1 mV dec−1 for UOR, outperforming most current catalysts. Our strategy features high designability in phase engineering, enabling various electrocatalysts to harness the power of unconventional phases. [ABSTRACT FROM AUTHOR]

The rapid pace of technology and increasing energy demands underscore the urgent need for eco-friendly materials with exceptional energy conversion and storage capabilities. Two-dimensional (2D) energy materials, characterized by unique physicochemical properties, hold great promise in renewable energy conversion, catalysis, and electronics. Nevertheless, conventional synthesis methods often falter in balancing high quality, high yield, and cost-effectiveness, presenting substantial obstacles to their large-scale application. Microwave-assisted synthesis, characterized by its rapid and efficient process, emerges as a promising approach to surmount these limitations. This review meticulously examines the pivotal role of microwave-assisted synthesis in the preparation of 2D materials, highlighting its profound impact on enhancing material quality and production efficiency. By scrutinizing the unique physical properties of microwaves and their applications in material synthesis, the review elucidates the innovative contributions of microwave technology to materials science. Furthermore, it delves into the intricate influence of microwave parameter control on the synthesis process and resultant material properties, offering insight into the potential of microwave technology for the precise modulation of material structure and functionality. This comprehensive analysis underscores microwave-assisted synthesis as a viable solution for overcoming current challenges, thereby advancing the development of high-performance 2D energy materials. [ABSTRACT FROM AUTHOR]

Amidst the pressing demand for carbon neutrality and clean energy policies, the electrocatalytic urea oxidation reaction (UOR) has gained attention as an efficient and environmentally friendly energy conversion pathway. High-valence/content two-dimensional (2D) nickel-based ABO3 perovskite oxides, particularly LaNiO3, are highlighted for their elevated intrinsic catalytic activity and rich electronic configuration advantages. To enhance the intrinsically limited conductivity of LaNiO3, a modified strategy involving B-site substitution can be used to construct a solid solution structure, significantly improving the electronic configuration. However, as Ni is the primary active site for the UOR, substituting the B-site will create a trade-off between enhancing electron migration and decreasing active site content. Specifically, conventional synthesis methods with a slow-entropy-change pose challenges in precise control over atomic ratios and 2D structure design, hindering elucidation of the impact mechanism of the electronic configuration on UOR performance. Herein, we utilized the microwave-pulse method for rapid synthesis of highly tunable 2D porous nickel-enriched LaMnxNi1−xO3 perovskite. Leveraging transient high-temperature and high-energy conditions, we achieved rapid one-step equilibrium between 2D porous structure design and precise control of solid solution atomic ratios. This strategy allows for the controlled synthesis of 2D nickel-enriched solid solutions with excellent conductivity and UOR activity, while effectively avoiding the generation of by-products, providing a detailed analysis of the UOR activity mechanism dependent on distinct electronic configurations. The synthesized LaMn0.2Ni0.8O3 structure exhibits optimal UOR performance. This strategy provides a new avenue for the design of more unique structured nickel-based solid solutions and the investigation of their structure–performance relationships in the electrocatalytic UOR. [ABSTRACT FROM AUTHOR]

Developing an efficient and stable oxygen evolution reaction (OER) catalyst is beneficial in various energy conversion and storage applications for achieving the "Carbon Neutrality" goal. Among the iron‐based perovskite oxides (AFeO3), LaFeO3 stands out as a preferred catalyst for electrocatalytic OER due to its exceptional selectivity in oxygen bonding at the A‐site. The introduction of A‐site substitution and controlled morphological engineering in perovskite structures has proven effective in enhancing the electrical conductivity and intrinsic catalytic activity. Nevertheless, the conventional A‐site substitution approach often involves prolonged high‐temperature calcination, leading to the agglomeration of nanostructures, particularly in two‐dimensional (2D) porous configurations. Herein, we introduce a novel method for synthesizing 2D porous LaFeO3 perovskite with A‐site Sr substitution using microwave shock. This microwave technique capitalizes on the benefits of transient heating and cooling, enabling simultaneous construction of 2D porous morphology and precise regulation of Sr substitution in one step. By conducting theoretical simulations of the electron configuration and analysis of crystal structure, we unveil the impact of Sr substitution on the OER activity of 2D porous LaFeO3. The synthesized La0.2Sr0.8FeO3 (LSFO‐8) catalyst exhibits an exceptional overpotential of 339 mV at 10 mA cm−2 and a small Tafel slope of 56.84 mV dec−1 in alkaline electrolyte. This investigation provides a fresh perspective for the design and engineering of electronic configuration in highly active 2D perovskite materials. [ABSTRACT FROM AUTHOR]