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Due to the hydrophilicity and black-phase instability of FA perovskites, ambient humidity is an unavoidable issue in the processing of perovskite solar cells (PSCs). MACl is among the most popular additives for improving perovskite films, but our experiments confirm that the direct addition of MACl into the precursor solution deteriorates the stability of the final α-FAPbI3 films in humid air, which is attributed to the unwanted pinholes induced by MACl volatilization. To solve this problem, a novel confined-space annealing strategy (CSA) is intentionally developed to control the amount of MACl at a low level. Through retarding the volatilization of MACl and blocking moisture ingress, dense and δ-phase-free FAPbI3 films with excellent crystallinity and stability are achieved at 100 °C under high humidity (RH: 60 ± 10%). We further compare the same amounts of MAI and FACl additives with MACl, discovering that only when MA and Cl work together can pure α-FAPbI3 films be obtained; therefore, a mechanism of MA-assisted nucleation and Cl-induced diffusion recrystallization is inferred. As a result, the PSCs employing optimal films yield a champion power conversion efficiency (PCE) of 17.27% and retain over 90% of the initial PCE after exposure to high humidity for 480 h. Our results offer deep insights into the thermodynamic and kinetic behaviors of MA and Cl in film growth and are beneficial for air-processed FA-based PSCs for commercial application. [ABSTRACT FROM AUTHOR]

This research aims to explore early concrete bridges in China, especially those from 1950s to 1970s, as a form of modern heritage. It asserts that there are inherent contradictions in how these bridges were perceived over half a century later. Although this may affect their listing as cultural heritage, it also makes them a representative case for a decentered approach to modern heritage not only at an international level, but also within a particular national context. In a country still building concrete bridges of ever‐increasing scales, early concrete bridges in China, despite their age, are seldom considered as cultural heritage. However, while historically and technologically these bridges were close to the everyday lived experiences, they are often more difficult to research than older, pre‐1949 buildings and structures. This is not only because of the lack of readily available archives, but also that these bridges, especially the iconic "double‐curved" bridges, which were politicized during the Great Proletarian Cultural Revolution (1966–1976), represented an important period in modern Chinese history that is still politically sensitive and contested, possessing cultural values that mean vastly different things for different people. This is illustrated by the case study of three bridges in Nanjing: the Yangtze River Bridge of Nanjing, arguably the most famous Chinese bridge in the twentieth century; the Little Egret Bridge (Bailu Bridge), an early double‐curved bridge, which is said to be a prototype of the former; and the Xiaolingwei Experimental Bridge, an important landmark in the development of the double‐curved bridge but entirely forgotten after the beginning of the Cultural Revolution in 1966. Accounts from before, during, and after the Cultural Revolution provide very different narratives about the process of their design and construction. Their different geographical locations and different associations with this turbulent and contested period of modern Chinese history also affects their conservation status today. All these factors combined make these bridges an exemplar of dissonant modern heritage that, although situated in a Chinese context, has important lessons globally for our understanding of the impact and legacies of modernity. [ABSTRACT FROM AUTHOR]

Non-flammable and oxidatively stable sulfones are promising electrolyte solvents for thermally stable high-voltage Li batteries. In addition, sulfolane-based high-concentration electrolytes (HCEs) show high Li+ ion transference numbers. However, LiPF6 has not yet been investigated as the main salt in sulfone-based HCEs for Li batteries. In this study, we investigated the phase behaviors, solvate structures, and transport properties of binary and ternary mixtures of LiPF6 and the following sulfone solvents: sulfolane (SL), dimethyl sulfone (DMS), ethyl methyl sulfone (EMS), and 3-methyl sulfolane (MSL). The stable crystalline solvates Li(SL)4PF6 and Li(DMS)2.5PF6 with high melting points were formed in the LiPF6/SL and LiPF6/DMS mixtures, respectively. In contrast, LiPF6/EMS, LiPF6/MSL, and LiPF6/SL/another sulfone mixtures remained liquids over a wide temperature range. Raman spectroscopy revealed that SL and another sulfone are competitively coordinated to Li+ ions to dissociate LiPF6 in the ternary mixtures. Although the ionic conductivity decreased with increasing LiPF6 concentration due to an increase in viscosity, Li+ ions diffused faster than PF6−via exchanging ligands in the HCE [LiPF6]/[SL]/[DMS] = 1/2/2, resulting in a higher Li ion transference number than that in conventional Li battery electrolytes. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSC) based on organic semiconductor materials that convert solar energy into electric energy have been constantly developing at present, and also an effective way to solve the energy crisis and reduce carbon emissions. In the past several decades, efforts have been made to improve the power conversion efficiency (PCE) of OSCs. During this period, a variety of structural and material forms of OSCs have evolved. Commercializing OSCs, extending their service life and exploring their future development are promising but challenging. In this review, we first briefly introduce the development of OSCs and then summarize and analyze the working principle, performance parameters, and structural features of OSCs. Finally, we highlight some breakthrough related to OSCs in detail. [ABSTRACT FROM AUTHOR]

The development of industry has triggered an increasingly severe demand for new functional materials. In recent years, researches on high‐entropy oxides (HEOs) are more comprehensive and in‐depth, and their fascinating properties are gradually known to the public. The unique elemental synergistic effect and lattice distortion endow the high‐entropy family with various untapped potential, and wide application fields and outstanding performance of HEOs make them candidates for future materials. In this review, the concept, structure, and synthesis of HEOs are firstly highlighted. Secondly, a variety of excellent properties and applications in the fields of mechanics, electrics, thermotics, optics and magnetics are summarized. This work provides a comprehensive overview about HEOs, facilitating the development of modern functionalities of the high‐entropy family. [ABSTRACT FROM AUTHOR]