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Perovskite solar cells (PSCs) have had a lasting impression on the scientific community because of their fast progress as high efficient and low-cost technology. [1] Starting from Kojima et al., in 2009, maximum power conversion efficiencies (PCEs) exceeding 25% have already been certified, resulting from crystallinity optimization, [2,3] morphology control, [4] interface engineering, [5,6] and defects passivation. [3,7,8] Several methods have been reported to prepare high-quality perovskite films, including thermal evaporation, twostep sequential deposition, vapor-assisted solution processing, and one-step spincoating method. [9] Although the simple, antisolvent-free, low-toxic, and time-consuming two-step method has been widely used in most of the high-efficiency PSCs with certified PCE exceeding 24%, [10][11][12] the quickly transformed perovskite often exhibit poor surface coverage with pinholes and high surface roughness, [13] which is related to the rapid reaction between the PbI 2 and the organic component (FAI, MABr, MACl, etc.). [14] More importantly, the polycrystalline perovskite usually contains a large number of structural disorders [15] and surface defects, [16] inducing severe degradation of photovoltaic performance. Defect inhibition in perovskite absorbers for enabling further photovoltaic and stability enhancement is still sluggish. Additive engineering by small molecule, inorganic salt, Lewisbased additives has been developed to control the crystallinity and surface defects in PSCs. [3,[17][18][19] Nevertheless, most of the additives are non-ABX 3 perovskite component units, so it is inevitable to introduce impurities. In particular, ionic liquids (ILs), which usually contain organic cations and pseudohalogen anions, are regarded as the ideal passivation materials for

Interfacial nonradiative recombination loss is a huge barrier to advance the photovoltaic performance. Here, one effective interfacial defect and carrier dynamics management strategy by synergistic modulation of functional groups and spatial conformation of ammonium salt molecules is proposed. The surface treatment with 3‐ammonium propionic acid iodide (3‐APAI) does not form 2D perovskite passivation layer while the propylammonium ions and 5‐aminopentanoic acid hydroiodide post‐treatment lead to the formation of 2D perovskite passivation layers. Due to appropriate alkyl chain length, theoretical and experimental results manifest that COOH and NH3+ groups in 3‐APAI molecules can form coordination bonding with undercoordinated Pb2+ and ionic bonding and hydrogen bonding with octahedron PbI64−, respectively, which makes both groups be simultaneously firmly anchored on the surface of perovskite films. This will strengthen defect passivation effect and improve interfacial carrier transport and transfer. The synergistic effect of functional groups and spatial conformation confers 3‐APAI better defect passivation effect than 2D perovskite layers. The 3‐APAI‐modified device based on vacuum flash technology achieves an alluring peak efficiency of 24.72% (certified 23.68%), which is among highly efficient devices fabricated without antisolvents. Furthermore, the encapsulated 3‐APAI‐modified device degrades by less than 4% after 1400 h of continuous one sun illumination.

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The defects (e.g., I2, anion, and cation vacancies) in the perovskite films are detrimental to the power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). Herein, a multifunctional additive molecule 4‐fluorophenylhydrazine hydrochloride (denoted as 4F‐PHCl) is reported, which can improve perovskite crystallization, passivate film defects, and enhance film moisture stability, finally leading to the simultaneous increase in PCE and stability. It is revealed that the hydrazine functional group can effectively reduce the I2 defects back to I‐. In addition, the hydrazinium contained cations and chloride anions can passivate the cationic defects (like anion vacancies) and anionic defects (like cation vacancies), respectively. The hydrophobic fluorinated benzene ring should be mainly responsible for the enhanced moisture stability of films and devices. As a result, the 4F‐PHCl‐modified device achieves a promising efficiency of 21.80% along with a high open‐circuit voltage of 1172 mV and exhibits excellent long‐term ambient stability. A guide for developing multifunctional additive molecules for the simultaneous enhancement of efficiency and stability is provided.

The optical properties and stability of metal halide perovskites can be improved by reducing their dimensionality. Because defects at the perovskite film grain body and boundaries cause significant energetic losses by nonradiative recombination, perovskite films with manageable crystal size and macroscopic grains are essential to improve the photovoltaic properties. Through theoretical calculation models and experiments, we show that the carboxyl group of 4-ammonium butyric acid-based cation (4-ABA+) can interact with the three-dimensional (3D) perovskite to produce in situ a secondary grain growth by post-treatment. It passivates the trap defects and broadens the light absorption. 4-ABA+ could induce a 2D capping layer on top of 3D mixed cation-based perovskite to construct a 2D/3D heterojunction. The 4-ABA+-modified perovskite film consists of large-sized grains with extremely low trap state densities and possesses a longer charge carrier lifetime and good stability, resulting in efficient perovskite solar cells with a champion efficiency of 23.16% and a V OC of 1.20 V. We show that the 4-ABA+-treated devices outperform the 3-ammonium propionic acid (3-APA+)- and 5-ammonium valeric acid (5-AVA+)-treated ones. Moreover, the devices exhibit high stability under high humidity and continuous light soaking conditions. This work gives a hint that our approach based on 4-ABA+ treatment is key to achieving better electrical properties, a controlled crystal growth, and highly stable perovskite solar cells.

Low dimensional interface passivation has been proved to be an efficient method to lessen the nonradiative recombination loss in perovskite solar cells. To overcome the limitation of Phenethylammonium (PEA+) for carrier transport and water molecule intrusion, we developed a modification strategy by functioning the typical PEA+ with the 4-methoxy to optimize the interface defects and carrier transport performance, thus maximizing the synchronous improvement of device efficiency and stability. Our results indicate that the 2 mg ml−1 4-methoxy-phenethylammonium (MeO-PEA+) modified device could achieve a best power conversion efficiency of 19.64% with improved shelf-life stability in ambient conditions. The new passivation molecule of MeO-PEA+ could possess the capability of defect passivation, carrier transfer, and moisture blocking, demonstrating that rationally designed organic components for interface passivation could help to achieve efficient and stable PSCs.

Objective Systemic inflammatory factors are independent risk factors in the formation and progression of various solid tumors. However, whether systemic inflammatory factors are associated with effect and prognosis of esophageal squamous cell carcinoma patients treated with immunotherapy remains unknown. The aim of this study is to assess the value of systemic inflammatory factors in the efficacy of camrelizumab for patients with advanced, metastatic esophageal squamous cell carcinoma. Methods We conducted a retrospective analysis of 90 patients with advanced, metastatic esophageal squamous cell carcinoma who received treatment with camrelizumab in Xinghua People’s Hospital between August 2019 and October 2021. The optimal cut-off values of platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR) and systemic immune-inflammation index (SII) for predicting efficacy and prognosis were identified based on the receiver operating characteristic (ROC) curve. Progression free survival (PFS) and overall survival (OS) were evaluated using the Kaplan–Meier method, and differences in PFS or OS between groups were compared by the Log rank test. Univariate and multivariate Cox proportional hazards regression models were performed to analyze prognostic values of each variable. Results The optimal cutoff values of PLR, NLR and SII predicted survival outcomes were 157.7, 3.84 and 750.8, respectively. Higher PLR, NLR and SII were associated with shorter PFS (HR for PLR = 2.899, P = 0.001; HR for NLR = 3.629, P < 0.001; HR for SII = 10.251, P < 0.001) and OS (HR for PLR = 4.583, P < 0.001; HR for NLR = 3.921, P < 0.001; HR for SII = 38.606, P < 0.001). Multivariate Cox regression analysis revealed that high PLR, NLR and SII were independent risk factors of PFS and OS in the advanced, metastatic esophageal squamous cell carcinoma patients receiving camrelizumab. Conclusion PLR, NLR and SII are potentially effective prognostic predictors in advanced, metastatic esophageal squamous cell carcinoma patients treated with camrelizumab.