Surface engineering has been shown critical for the success of perovskite solar cells by passivating the surface enriched defects and mobile species. The discovery of surface modulators with superior interaction strength to perovskite is of paramount importance since they can retain reliable passivation under various environments. Here, we report a chelation strategy for surface engineering of CsPbI₂Br perovskite, in which dithiocarbamate molecules can be coordinate to surface Pb sites via strong bidentate chelating bonding. Such chelated CsPbI₂Br perovskite can realize excellent passivation of surface under-coordinated defects, reaching a champion power conversion efficiency of 17.03% and an open-circuit voltage of 1.37 V of CsPbI₂Br solar cells. More importantly, our chelation strategy enabled excellent device stability by maintaining 98% of their initial efficiency for over 1400 h in ambient condition. Our findings provide scientific insights on the surface engineering of perovskite that can facilitate the further development and application of perovskite optoelectronics.

Molybdenum disulfide (MoS₂) is a promising layer-structured material for use in many applications due to its tunable structural and electronic properties in terms of its structural phases. Its performance including efficiency and durability is often dependent on its mechanical properties. To understand the effects of the structural phase on its mechanical properties, a comparative study on the mechanical properties of bulk 2H, 3R, 1T, and 1T′ MoS₂ was conducted using the first-principles density functional theory. Since considerable applications of MoS₂ are developed through strain engineering, the impact of the external pressure on its mechanical properties was also considered. Our results suggest a strong relationship between the mechanical properties of MoS₂ and the structural symmetry of its crystal. Accordingly, the impacts of the external pressure on the mechanical properties of MoS₂ also greatly vary with respect to the structural phases. Among all of the considered phases, the 2H and 3R MoS₂ have a larger bulk modulus, Young’s modulus, shear modulus, and microhardness due to their higher stability. Conversely, 1T and 1T′ MoS₂ are less strong. As such, 1T and 1T′ MoS₂ can be a better candidate for strain engineering.

Urea is not only a primary fertilizer in modern agriculture but also a crucial raw material for the chemical industry. In the past hundred years, the prevailing industrial synthesis of urea heavily relies on the Bosch–Meiser process to couple NH₃ and CO₂ under harsh conditions, resulting in high carbon emissions and energy consumption. The conversion of carbon‐ and nitrogen‐containing species into urea through electrochemical reactions under ambient conditions represents a sustainable strategy. Despite the increasing reports on urea electrosynthesis, a comprehensive review that delves into a profound, atomic‐level comprehension of the fundamental reaction mechanisms is currently absent. In this Perspective, recent advancements in electrochemical urea synthesis from CO₂/CO and various nitrogenous species (i.e., N₂, NO_x⁻, and NO) under ambient conditions are presented, with special emphasis on theoretical understanding of the C─N coupling reaction mechanisms. Several key strategies to facilitate the C─N coupling are then pinpointed, which not only enhance their applicability in practical experiments but also highlight the significant progress achieved in this field. At the end, the major obstacles and potential opportunities in advancing urea electrosynthesis accelerated by theoretical simulations and in situ techniques are discussed. This review is hoped to act as a roadmap to ignite fresh insights and inspiration for the development of electrocatalytic urea synthesis.