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With excellent biocompatibility, a narrow bandgap, and long thermal carrier lifetime, tin‐based perovskite solar cells (TPSCs) are promising within the solar technology. The fullerene derivative indene‐C60 bisadduct (ICBA) is recognized as the most efficient electron‐transport material for TPSCs, thanks to its suitable band structure. Nevertheless, the limited electron transport capability and susceptibility to moisture penetration of ICBA have hindered the progress of TPSCs. Herein, the study proposes a new hydrophobic electron‐transport layer (ETL) comprising a surface‐anchored non‐fullerene n‐type semiconducting polymer layer, poly (naphthalene diimide‐alt‐dithiophenebezothiadiazole) (PNDI‐BT), in conjunction with ICBA. PNDI‐BT exhibits high electron mobilities, a fitting band structure, robust interaction with Sn‐based perovskites, and exceptional moisture resistance, effectively addressing the shortcomings of ICBA. Consequently, this innovative hydrophobic ETL of PNDI‐BT/ICBA enhances electron transport and protects Sn‐based perovskites from moisture. As a result, the inverted TPSCs with the new hydrophobic ETL achieve an impressive efficiency of 13.90%, surpassing TPSCs with the ICBA layer (12.75%). Moreover, even after 1000 h of storage in ambient atmosphere, the encapsulated TPSC maintains a remarkable 81% of its initial efficiency. This comprehensive study seamlessly integrates the synthesis of non‐fullerene n‐type semiconducting polymer and device fabrication, providing valuable insights into designing cutting‐edge ETL structure for inverted TPSCs. [ABSTRACT FROM AUTHOR]

Energy loss in perovskite grain boundaries (GBs) is a primary limitation toward high‐efficiency perovskite solar cells (PSCs). Two critical strategies to address this issue are high‐quality crystallization and passivation of GBs. However, the established methods are generally carried out discretely due to the complicated mechanisms of grain growth and defect formation. In this study, a combined method is proposed by introducing 3,4,5‐Trifluoroaniline iodide (TFAI) into the perovskite precursor. The TFAI triggers the union of nano‐sized colloids into microclusters and facilitates the complete phase transition of α‐FAPbI3 at room temperature. The controlled chemical reactivity and strong steric hindrance effect enable the fixed location of TFAI and suppress defects at GBs. This combination of well‐crystallized perovskite grains and effectively passivated GBs leads to an improvement in the open circuit voltage (Voc) of PSCs from 1.08 V to 1.17 V, which is one of the highest recorded Voc without interface modification. The TFAI‐incorporated device achieved a champion PCE of 24.81%. The device maintained a steady power output near its maximum power output point, showing almost no decay over 280 h testing without pre‐processing. [ABSTRACT FROM AUTHOR]

Diatoms play an important role in the biogeochemical cycling of aluminum (Al) in oceans. This occurs via the uptake of biological Al (Albio), which is incorporated into the structure of diatom‐derived biogenic silica (DBSi) and the formation of adsorbed Al (Alads) on the DBSi surface of post‐mortem diatoms. Al occurrence influences DBSi dissolution and thus diatom‐driven carbon sequestration. However, the mechanism of Al occurrence in DBSi remains unclear. In this study, Albio and Alads of DBSi from various diatom fossils in marine diatomaceous sediments were identified and quantified by combined focused ion beam thinning, elemental analysis, and the Al K‐edge X‐ray absorption near edge structure. Results showed the coexistence of Albio and Alads in all diatomaceous sediments and Al‐bearing DBSi thus constitutes a biological Al pool. Albio and Alads were mainly fourfold‐ and sixfold‐coordinated, respectively and Alads was much more abundant than Albio. Moreover, even at low concentrations (with an Al/Si atomic ratio of 0.0031), Albio can inhibit DBSi dissolution, effectively decreasing the extent of DBSi dissolution by ∼14%. Albio also significantly increased the mechanical strength of DBSi. The average Young's modulus (a measure of the stiffness of a material) of cribrum layers in Al‐incorporated DBSi was ∼1.4 times higher than that of Al‐free DBSi. Our results further demonstrate that diatoms play a dominant role in the biogeochemical cycling of Al in oceans, and the Al of DBSi participates in diatom‐driven Si and C coupled cycles in oceans, influencing the effectiveness of diatom‐driven carbon export by regulating the dissolution and mechanical strength of DBSi. Plain Language Summary: Diatoms contribute to oceanic carbon sequestration by exporting carbon from the ocean's surface to its depths. Aluminum (Al) is taken up by living diatoms to be incorporated into the structure of diatom‐derived biogenic silica (DBSi) (biogenic Al) and adsorbed by DBSi of post‐mortem diatoms (adsorbed Al). Al can inhibit the dissolution of DBSi and thus influence carbon sequestration. However, the mechanism of Al occurrence in DBSi remains unclear. Herein, we identified and quantified Al in DBSi from various diatom fossils using nano‐scaled microscopic analyses and investigated the influence of Al on DBSi properties. The results showed that biogenic Al and adsorbed Al have different coordination states in DBSi, and adsorbed Al was much more abundant than biogenic Al. The trace presence of biogenic Al effectively decreased the extent of DBSi dissolution by ∼14%. Moreover, biogenic Al influenced the properties of DBSi—the mechanical strength of Al‐incorporated DBSi was much higher than that of Al‐free DBSi. These results indicate that Al taken up by living diatoms noticeably influences the chemical and physical properties of diatom shells, which impacts the effectiveness of carbon export by diatoms. Key Points: Coupled Si–Al biogeochemistry was revealed by investigating the occurrence of Al in diatom‐derived biogenic silica (DBSi)Nano‐scaled microscopic analyses were performed to identify and quantify Al in DBSi, which constitutes a biological Al poolAl effectively inhibits DBSi dissolution and significantly increases the mechanical strength of DBSi [ABSTRACT FROM AUTHOR]

The low toxicity and a near‐ideal bandgap endow tin (Sn)‐based perovskite solar cells (TPSCs) a promising future in photovoltaic technologies. However, in general the Sn‐based perovskites suffer from poor resistance to oxidation and fast crystallization dynamics, resulting in low fill factors (FFs) and power conversion efficiencies (PCEs). Herein, a strategy to improve the performance of TPSCs by incorporating 2‐(2‐aminoethyl)–2‐thiopseudourea dihydrobromide (AET) into the Sn‐based perovskites is proposed. AET interacts strongly with the Sn‐based perovskites, and thus effectively inhibits the oxidation from Sn2+ to Sn4+ and slows down the crystallization process. As a result, the TPSCs with AET achieve a high FF of 80.26% and a high PCE of 13.55%. Notably, this FF value represents the highest reported in the field of TPSCs with narrow bandgaps. Furthermore, encapsulated TPSCs demonstrate good stability, maintaining 80% of their initial performance over the course of 700 h. [ABSTRACT FROM AUTHOR]

The fragile bottom side of perovskite films is demonstrated to be harmful to the efficiency and stability of perovskite solar cells (PSCs) because the carrier extraction and recombination can be significantly influenced by the easily formed strain, voids, and defects on the bottom side. Nevertheless, the bottom side of perovskite films is usually overlooked because it remains a challenge to directly characterize and modify the bottom side. Herein, a facile and effective strategy is reported to stabilize the bottom side via preburying cesium formate (CsFo) into the SnO2 electron transport layer (ETL). It is found that the synergistic effect of cesium cation (Cs+) and formate anion (HCOO−) causes strain relaxation, void elimination, and defects' reduction, which further facilitate the charge extraction. Consequently, the champion power conversion efficiency (PCE) of formamidinium (FA)‐based PSCs is increased from 23.34% to 24.50%. Meanwhile, the ultraviolet (UV), thermal, and operational stability are also enhanced. Finally, formamidinium–cesium (FACs)‐based PSCs are investigated to confirm the effectiveness of this preburied CsFo strategy, and the optimal device exhibits a champion PCE of 25.03% and a remarkably high fill factor (FF) of 85.65%. [ABSTRACT FROM AUTHOR]

Realization of remote wearable health monitoring (RWHM) technology for the flexible photodiodes is highly desirable in remote‐sensing healthcare systems used in space stations, oceans, and forecasting warning, which demands high external quantum efficiency (EQE) and detectivity in NIR region. Traditional inorganic photodetectors (PDs) are mechanically rigid and expensive while the widely reported solution‐processed mixed tin‐lead (MSP) perovskite photodetectors (PPDs) exhibit a trade‐off between EQE and detectivity in the NIR region. Herein, a novel functional passivating antioxidant (FPA) strategy has been introduced for the first time to simultaneously improve crystallization, restrain Sn2+ oxidization, and reduce defects in MSP perovskite films by multiple interactions between thiophene‐2‐carbohydrazide (TAH) molecules and cations/anions in MSP perovskite. The resultant solution‐processed rigid mixed Sn–Pb PPD simultaneously achieves high EQE (75.4% at 840 nm), detectivity (1.8 × 1012 Jones at 840 nm), ultrafast response time (trise/tfall = 94 ns/97 ns), and improved stability. This work also highlights the demonstration of the first flexible photodiode using MSP perovskite and FPA strategy with remarkably high EQE (75% at 840 nm), and operational stability. Most importantly, the RWHM is implemented for the first time in the PIN MSP perovskite photodiodes to remotely monitor the heart rate of humans at rest and after‐run conditions. [ABSTRACT FROM AUTHOR]