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Achieving high‐performance perovskite solar cells hinges on the precise management of interfacial properties. However, the current research predominantly concentrates on addressing individual interfaces, often overlooking the potential synergies between the upper and lower interfaces crucial for efficient carrier transfer. Herein, an effective interfacial strategy is introduced, which combines 2‐aminoterephthalic acid (2‐AA) pre‐processing with post‐processing techniques to prepare superior mixed tin‐lead perovskite films suitable for both single‐junction and all‐perovskite tandem solar cells. Incorporating 2‐AA at both the upper and lower interfaces of the perovskite films serves to regulate interfacial defects, alleviate interface residual stress, and improve film crystallinity. In addition, the 2‐AA molecule acts as an interface protective layer, anchoring tin and lead atoms, facilitating band energy alignment, and improving film and device stability. As a result, mixed tin‐lead perovskite solar cells achieved an improved open‐circuit voltage of 0.87 V and PCE of 21.57%. Furthermore, the integration of these optimized tin‐lead perovskite subcells into four‐terminal all‐perovskite tandem solar cells yielded an impressive efficiency of 27.46%. This work thus offers an effective strategy for comprehensive interfacial engineering and stress relief, paving the way for the production of high‐performance perovskite solar cells (PSCs). [ABSTRACT FROM AUTHOR]

This study explored the potential of ultrafine kaolin as a geopolymer raw material, focusing on the reactivity of calcined kaolin products and its influencing factors. Through a series of analytical techniques, including thickening experiments, particle size analysis, SEM, XRD, and FT-IR, the effects of calcination temperature, time, and Si-Al ratio were evaluated. The results indicated that calcination temperature significantly impacts reactivity, with optimal conditions found between 600 °C and 800 °C, yielding metakaolin with thickening times of 12 to 43 min. Temperatures above 900 °C led to the formation of low-reactivity phases like mullite. The Si-Al ratio also influenced thickening time, with durations varying from 97 min at 0.85 to 43 min at 0.9 and increasing to 157 min at 0.95. Calcination time had the smallest effect, with thickening times ranging from 10 to 25 min over 4 to 8 h. Additionally, calcination altered particle size, initially expanding due to thermal expansion and later shrinking due to lattice distortion above 700 °C. By adjusting these parameters, the reactivity of calcined kaolin could be tailored to suit specific needs. This research provides a theoretical foundation for metakaolin's application in construction materials and offers novel insights into geopolymer preparation. [ABSTRACT FROM AUTHOR]

Tin‐lead (Sn‐Pb) mixed perovskite solar cells (PSCs), which serve as bottom subcells in all‐perovskite tandem solar cells, are pivotal for developing highly efficient solar cells. However, the vulnerability of stannous (Sn2+) to spontaneous oxidation to harmful tetravalent tin (Sn4+) presents significant challenges. Here, a “mouse glue trap” strategy is proposed to mitigate this issue by introducing a multifunctional additive, oxamidic acid potassium salt (OAPS). This approach effectively traps undesired Sn4+ impurities through strong interactions between the oxaminic acid groups of OAPS and Sn4+ impurities. Additionally, OAPS, with its unique functional groups, can inhibit Sn2+ oxidation, passivate defects, alleviate stress, and improve crystalline quality in Sn‐Pb mixed perovskite films. As a result, the enhanced Sn‐Pb mixed narrow‐bandgap PSCs incorporating OAPS achieve a power conversion efficiency of 22.04% and exhibit improved storage stability, with 91% retention after 3072 h of storage in an N2‐filled glovebox. Moreover, all‐perovskite tandem cells using OAPS‐incorporated Sn‐Pb narrow‐bandgap PSCs as subcells demonstrate efficiencies of 27.17% and 28.31% for two‐terminal and four‐terminal tandems, respectively, presenting a straightforward approach to optimizing performance in Sn‐Pb mixed PSCs and their tandems. [ABSTRACT FROM AUTHOR]

Relative to suppressed conductometric anion exchange chromatography, conductometric ion exclusion chromatography (IEC) is much less popular. Poor limit of detection and manual preparation of eluent are primarily responsible for this. We describe an electrodialytic phosphoric eluent generator for the online production of phosphoric acid eluent at a concentration exceeding 35 mM. It is a sandwiched configuration consisting of three channels isolated by stacked anion exchange membranes and a bipolar membrane plus stacked anion exchange membrane. Such a unique configuration ensures the production of gas‐free eluent, obviating the need for a gas removal device. The resulting eluent concentration is controlled by varying the current. Coupled with an ultraviolet absorbance detector, a 0.04–16.67 mg/L limit of detection for model organic acids was achieved by IEC equipped with an electrodialytic phosphoric eluent generator. [ABSTRACT FROM AUTHOR]