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Efficient electron transport layer–free perovskite solar cells (ETL‐free PSCs) with cost‐effective and simplified design can greatly promote the large area flexible application of PSCs. However, the absence of ETL usually leads to the mismatched indium tin oxide (ITO)/perovskite interface energy levels, which limits charge transfer and collection, and results in severe energy loss and poor device performance. To address this, a polar nonconjugated small‐molecule modifier is introduced to lower the work function of ITO and optimize interface energy level alignment by virtue of an inherent dipole, as verified by photoemission spectroscopy and Kelvin probe force microscopy measurements. The resultant barrier‐free ITO/perovskite contact favors efficient charge transfer and suppresses nonradiative recombination, endowing the device with enhanced open circuit voltage, short circuit current density, and fill factor, simultaneously. Accordingly, power conversion efficiency increases greatly from 12.81% to a record breaking 20.55%, comparable to state‐of‐the‐art PSCs with a sophisticated ETL. Also, the stability is enhanced with decreased hysteresis effect due to interface defect passivation and inhibited interface charge accumulation. This work facilitates the further development of highly efficient, flexible, and recyclable ETL‐free PSCs with simplified design and low cost by interface electronic structure engineering through facile electrode modification. A polar nonconjugated small molecule ultrathin layer with an intrinsic dipole moment is introduced to modify the work function of indium tin oxide and to optimize the front interface energy level alignment, which contributes to suppressed energy loss and results in a 20.55% efficient electron transport layer–free perovskite solar cell with enhanced open‐circuit voltage short circuit current density and fill factor, simultaneously.

The Social Responsiveness Scale (SRS) is an established tool for screening autism. An increasing number of studies have utilized the SRS in the general population as an outcome measure to gain insight into the etiology of autism spectrum disorder (ASD). However, SRS scores have not been well characterized in large pediatric cohorts, particularly in relation to their demographic, genetic, neuroimaging, and comorbidity profiles, or how these patterns compare to those observed in clinically diagnosed ASD. This study included 9788 non-ASD children and 182 autistic children aged 9–11 years from the Adolescent Brain Cognitive Development Study. Generalized linear mixed-effect models were applied to evaluate the associations of short social responsiveness scale (SSRS) with a spectrum of demographic, genetic, neuroimaging, and behavioral characteristics. We estimated the heritability of SSRS using a subsample of twin and sibling data. Our finding revealed that children with higher SSRS exhibited a higher male-to-female ratio. SSRS had a high heritability of 0.52 (95% CI, 0.45–0.63), and higher SSRS scores were correlated with increased polygenic risk for ASD (P < 0.001). Neuroimaging analyses identified both overlapping and unique neurobiological underpinnings, with sex-specific variations in structural and functional connectivity similar to those observed in ASD. Higher SSRS scores were linked to lower fluid intelligence, more behavioral problems, more sleep problems, and more psychotic-like symptoms. These findings highlight both the overlap and distinction between patterns reflected in SSRS scores and those observed in clinical ASD, highlighting the need for caution when interpreting findings only utilizing SRS as the outcome for autistic-like trait.

Background Previous studies have linked adolescent motherhood to adverse neurodevelopmental outcomes in offspring, yet the sex-specific effect and underlying mechanisms remain unclear. Methods This study included 6952 children aged 9–11 from the Adolescent Brain Cognitive Development study. The exposed group consisted of children of mothers < 20 years at the time of birth, while the unexposed group was composed of children of mothers aged 20–35 at birth. We employed a generalized linear mixed model to investigate the associations of adolescent motherhood with cognitive, behavioral, and autistic-like traits in offspring. We applied an inverse-probability-weighted marginal structural model to examine the potential mediating factors including adverse perinatal outcomes, family conflict, and brain structure alterations. Results Our results revealed that children of adolescent mothers had significantly lower cognitive scores (β, − 2.11, 95% CI, − 2.90 to − 1.31), increased externalizing problems in male offspring (mean ratio, 1.28, 95% CI, 1.08 to 1.52), and elevated internalizing problems (mean ratio, 1.14, 95% CI, 0.99 to 1.33) and autistic-like traits (mean ratio, 1.22, 95% CI, 1.01 to 1.47) in female. A stressful family environment mediated ~ 70% of the association with internalizing problems in females, ~ 30% with autistic-like traits in females, and ~ 20% with externalizing problems in males. Despite observable brain morphometric changes related to adolescent motherhood, these did not act as mediating factors in our analysis, after adjusting for family environment. No elevated rate of adverse perinatal outcomes was observed in the offspring of adolescent mothers in this study. Conclusions Our results reveal distinct sex-specific neurodevelopmental outcomes impacts of being born to adolescent mothers, with a substantial mediating effect of family environment on behavioral outcomes. These findings highlight the importance of developing sex-tailored interventions and support the hypothesis that family environment significantly impacts the neurodevelopmental consequences of adolescent motherhood.

Tin‐lead (Sn‐Pb) mixed perovskite with a narrow bandgap is an ideal candidate for single‐junction solar cells approaching the Shockley‐Queisser limit. However, due to the easy oxidation of Sn2+, the efficiency and stability of Sn‐Pb mixed perovskite solar cells (PSCs) still lag far behind that of Pb‐based solar cells. Herein, highly efficient and stable FA0.5MA0.5Pb0.5Sn0.5I0.47Br0.03 compositional PSCs are achieved by introducing an appropriate amount of multifunctional Tin (II) oxalate (SnC2O4). SnC2O4 with compensative Sn2+ and reductive oxalate group C2O42− effectively passivates the cation and anion defects simultaneously, thereby leading to more n‐type perovskite films. Benefitting from the energy level alignment and the suppression of bulk nonradiative recombination, the Sn‐Pb mixed perovskite solar cell treated with SnC2O4 achieves a power conversion efficiency of 21.43%. More importantly, chemically reductive C2O42− effectively suppresses the notorious oxidation of Sn2+, leading to significant enhancement in stability. Particularly, it dramatically improves light stability. Herein, highly efficient mixed Sn‐Pb PSCs are achieved by introducing multifunctional Tin (II) oxalate (SnC2O4). SnC2O4 with compensative Sn2+ and passivate defect, reduce Sn4+ and eliminate SnF2 and PbI2 residues. The device treats with SnC2O4 achieve a PCE of 21.43%. More importantly, chemically reductive C2O42‐ effectively suppresses the oxidation of Sn2+, leading to significant enhancement on stability.

The poor film stability of Sn-Pb mixed perovskite film and the mismatched interface energy levels pose significant challenges in enhancing the efficiency of tin–lead (Sn-Pb) mixed perovskite solar cells. In this study, polyvinylpyrrolidone (PVP) is introduced into the PVK perovskite precursor solution, effectively enhancing the overall stability of the film. This improvement is achieved through the formation of robust coordination bonds between the carbonyl (C=O) in the pyrrole ring and the undercoordinated SnII and PbII, thereby facilitating the passivation of defects. Furthermore, the introduction of PVP inhibits the oxidation of tin (Sn), thereby enhancing the n-type characteristics of the perovskite film. This adjustment in the energy level of the PVK perovskite film proves instrumental in reducing interface energy loss, subsequently improving interface charge transfer and mitigating device recombination. Consequently, perovskite solar cells incorporating PVP achieve an outstanding champion power conversion efficiency (PCE) of 21.31%.

The bandgap of inorganic halide perovskites plays a crucial role in the efficiency of solar cells. Although density functional theory can be used to calculate the bandgap of materials, the method is time-consuming and requires deep knowledge of theoretical calculations, theoretical calculations are frequently constrained by complex electronic correlations and lattice dynamics, resulting in discrepancies between calculated and experimental results. To address this issue, this study employs machine learning to predict the bandgap of inorganic halide perovskites. The XGBoost classifier classifies ABX 3 -type inorganic halide perovskites into narrow and wide bandgap materials. The study collected a dataset consisting of 447 perovskites and generated material descriptors using the Matminer Python package. The model predicts narrow-bandgap materials with 95% accuracy. Finally, the Shapley analysis revealed that the key factor affecting the bandgap of perovskites is the electronegativity range. As the range of electronegativity increases, so does the possibility of a perovskite with a narrow bandgap. These findings highlight the powerful ability of machine learning to quickly and accurately predict the bandgap of perovskites.

Parental psychopathology is a known risk factor for child autistic-like traits. However, symptom-level associations and underlying mechanisms are poorly understood. We utilized network analyses and cross-lagged panel models to investigate the specific parental psychopathology related to child autistic-like traits among 8,571 adolescents (mean age, 9.5 years at baseline), using baseline and 2-year follow-up data from the Adolescent Brain Cognitive Development study. Parental psychopathology was measured by the Adult Self Report, and child autistic-like traits were measured by three methods: the Kiddie Schedule for Affective Disorders and Schizophrenia for DSM-5 autism spectrum disorder (ASD) subscale, the Child Behavior Checklist ASD subscale, and the Social Responsiveness Scale. We also examined the mediating roles of family conflict and children's functional brain connectivity at baseline. Parental attention-deficit/hyperactivity problems were central symptoms and had a direct and the strongest link with child autistic-like traits in network models using baseline data. In longitudinal analyses, parental attention-deficit/hyperactivity problems at baseline were the only significant symptoms associated with child autistic-like traits at 2-year follow-up (  = 0.014, 95% confidence interval [0.010, 0.018], FDR  = 0.005), even accounting for children's comorbid behavioral problems. The observed association was significantly mediated by family conflict (proportion mediated = 11.5%, for indirect effect <0.001) and functional connectivity between the default mode and dorsal attention networks (proportion mediated = 0.7%, for indirect effect = 0.047). Parental attention-deficit/hyperactivity problems were associated with elevated autistic-like traits in offspring during adolescence.

COVID-19 lockdowns increased the risk of mental health problems, especially for children with autism spectrum disorder (ASD). However, despite its importance, little is known about the protective factors for ASD children during the lockdowns. Based on the Shanghai Autism Early Developmental Cohort, 188 ASD children with two visits before and after the strict Omicron lockdown were included; 85 children were lockdown-free, while 52 and 51 children were under the longer and the shorter durations of strict lockdown, respectively. We tested the association of the lockdown group with the clinical improvement and also the modulation effects of parent/family-related factors on this association by linear regression/mixed-effect models. Within the social brain structures, we examined the voxel-wise interaction between the grey matter volume and the identified modulation effects. Compared with the lockdown-free group, the ASD children experienced the longer duration of strict lockdown had less clinical improvement ( = 0.49, 95% confidence interval (CI) [0.19-0.79], = 0.001) and this difference was greatest for social cognition (2.62 [0.94-4.30], = 0.002). We found that this association was modulated by parental agreeableness in a protective way (-0.11 [-0.17 to -0.05], = 0.002). This protective effect was enhanced in the ASD children with larger grey matter volumes in the brain's mentalizing network, including the temporal pole, the medial superior frontal gyrus, and the superior temporal gyrus. This longitudinal neuroimaging cohort study identified that the parental agreeableness interacting with the ASD children's social brain development reduced the negative impact on clinical symptoms during the strict lockdown.

Lewis-base polymers have been widely utilized as additives to act as a template for the perovskite nucleation/crystal growth and passivate the under-coordinated Pb 2+ sites. However, it is uncovered in this work that the polymer on the perovskite grain boundaries would significantly hinder the charge transport due to its low conductivity, which brings about free carrier recombination and photocurrent losses. To circumvent this issue while fully exploiting the benefits of polymers in passivating the trap states in perovskite, we incorporate highly conductive multiwall carbon nanotubes (CNTs) with Lewis-base polymers as co-additives in the perovskite film. Functionalizing the CNTs with -COOH group enables a selective hole-extraction and charge transport from perovskite to the hole transporting materials (HTM). By studying the charge transporting and recombination dynamics, we revealed the individual role of the polymer and CNTs in passivating the trap states and facilitating the charge transport, respectively. As a result, the perovskite solar cells (PSCs) with polymer-CNTs composites exhibit an impressive PCE of 21.7% for a small-area device (0.16 cm 2 ) and 20.7% for a large-area device (1.0 cm 2 ). Moreover, due to the superior mechanical flexibility of both polymer and CNTs, the polymer-CNTs composites incorporation in the perovskite film encourages the fabrication of flexible PSCs (f-PSCs) with an impressive PCE of 18.3%, and a strong mechanical durability by retaining 80% of the initial PCE after 1,000 times bending. In addition, we proved that the selection criteria of the polymers can be extended to other long-chain Lewis-base polymers, which opens new possibilities in design and synthesis of inexpensive material for this tactic towards the fabrication of high performance large-area PSCs and f-PSCs.

Tin‐lead (Sn‐Pb) mixed perovskite with a narrow bandgap is an ideal candidate for single‐junction solar cells approaching the Shockley‐Queisser limit. However, due to the easy oxidation of Sn 2+ , the efficiency and stability of Sn‐Pb mixed perovskite solar cells (PSCs) still lag far behind that of Pb‐based solar cells. Herein, highly efficient and stable FA 0.5 MA 0.5 Pb 0.5 Sn 0.5 I 0.47 Br 0.03 compositional PSCs are achieved by introducing an appropriate amount of multifunctional Tin (II) oxalate (SnC 2 O 4 ). SnC 2 O 4  with compensative Sn 2+ and reductive oxalate group C 2 O 4 2− effectively passivates the cation and anion defects simultaneously, thereby leading to more n‐type perovskite films. Benefitting from the energy level alignment and the suppression of bulk nonradiative recombination, the Sn‐Pb mixed perovskite solar cell treated with SnC 2 O 4 achieves a power conversion efficiency of 21.43%. More importantly, chemically reductive C 2 O 4 2− effectively suppresses the notorious oxidation of Sn 2+ , leading to significant enhancement in stability. Particularly, it dramatically improves light stability.