Neural topic models with survival supervision: Jointly predicting time-to-event outcomes and learning how clinical features relate.

We present a neural network framework for learning a survival model to predict a time-to-event outcome while simultaneously learning a topic model that reveals feature relationships. In particular, we model each subject as a distribution over "topics", where a topic could, for instance, correspond to an age group, a disorder, or a disease. The presence of a topic in a subject means that specific clinical features are more likely to appear for the subject. Topics encode information about related features and are learned in a supervised manner to predict a time-to-event outcome. Our framework supports combining many different topic and survival models; training the resulting joint survival-topic model readily scales to large datasets using standard neural net optimizers with minibatch gradient descent. For example, a special case is to combine LDA with a Cox model, in which case a subject's distribution over topics serves as the input feature vector to the Cox model. We explain how to address practical implementation issues that arise when applying these neural survival-supervised topic models to clinical data, including how to visualize results to assist clinical interpretation. We study the effectiveness of our proposed framework on seven clinical datasets on predicting time until death as well as hospital ICU length of stay, where we find that neural survival-supervised topic models achieve competitive accuracy with existing approaches while yielding interpretable clinical topics that explain feature relationships. Our code is available at: https://github.com/georgehc/survival-topics.

High Thermal Conductivity and Radiative Cooling Designed Boron Nitride Nanosheets/Silk Fibroin Films for Personal Thermal Management.

The implementation of passive cooling strategies is crucial for transitioning from the current high-power- and energy-intensive thermal management practices to more environmentally friendly and carbon-neutral alternatives. Among the various approaches, developing thermal management materials with high thermal conductivity and emissivity for effective cooling of personal and wearable devices in both indoor and outdoor settings poses significant challenges. In this study, we successfully fabricated a cooling patch by combining biodegradable silk fibroin with boron nitride nanosheets. This patch exhibits consistent heat dissipation capabilities under different ambient conditions. Leveraging its excellent radiative cooling efficiency (Rsolar = 0.89 and εLWIR = 0.84) and high thermal conductivity (in-plane 27.58 W m-1 K-1 and out-plane 1.77 W m-1 K-1), the cooling patch achieves significant simulated skin temperature reductions of approximately 2.5 and 8.2 °C in outdoor and indoor conditions, respectively. Furthermore, the film demonstrates excellent biosafety and can be recycled and reused for at least three months. This innovative BNNS/SF film holds great potential for advancing the field of personal thermal management materials.

Anisotropic Black Phosphorene Structural Modulation for Thermal Storage and Solar-Thermal Conversion.

Exploiting novel strategies for simultaneously harvesting ubiquitous, renewable, and easily accessible solar energy based on the photothermal effect, and efficiently storing the acquired thermal energy plays a vital role in revolutionizing the current fossil fuel-dominating energy structure. Developing black phosphorene-based phase-change composites with optimized photothermal conversion efficiencyand high latent heat is the most promising way to achieve efficient solar energy harvesting and rapid thermal energy storage. However, exfoliating high-quality black phosphorene nanosheets  remains challenging, Furthermore, an efficient strategy that can construct the aligned black phosphorene frameworks to maximize thermal conductivity enhancement is still lacking. Herein, high-quality black phosphorene nanosheets are prepared by an optimized exfoliating strategy. Meanwhile, by regulating the temperature gradient during freeze-casting, the framework consisting of shipshape aligned black phosphorene at long-range is successfully fabricated, improving the thermal conductivity of the poly(ethylene glycol) matrix up to 1.81 W m-1  K-1 at 20 vol% black phosphorene loading. The framework also endows the composite with excellent phase-change material encapsulation capacity and  high latent heat of 103.91 J g-1 . It is envisioned that the work advances the paradigm of contrasting frameworks with nanosheets toward controllable structure thermal enhancement of the composites.

Molecular mechanisms and therapeutic potential of icariin in the treatment of Alzheimer's disease.

BACKGROUND: Icariin (ICA) is the main active component of Epimedium, a traditional Chinese medicine (TCM), known to enhance cognitive function in Alzheimer's disease (AD). This study aims to investigate and summarize the mechanisms through which ICA treats AD. METHODS: The PubMed and CNKI databases were utilized to review the advancements in ICA's role in AD prevention and treatment by analyzing literature published between January 2005 and April 2023. To further illustrate ICA's impact on AD development, tables, and images are included to summarize the relationships between various mechanisms. RESULTS: The study reveals that ICA ameliorates cognitive deficits in AD model mice by modulating Aß via multiple pathways, including BACE-1, NO/cGMP, Wnt/Ca2+, and PI3K/Akt signaling. ICA exhibits neuroprotective properties by inhibiting neuronal apoptosis through the suppression of ER stress in AD mice, potentially linked to NF-κB, MAPK, ERK, and PERK/Eif2α signaling pathways. Moreover, ICA may safeguard neurons by attenuating mitochondrial oxidative stress injury. ICA can also enhance learning, memory, and cognition by improving synaptic structure via regulation of the PSD-95 protein. Furthermore, ICA can mitigate neuroinflammation by inactivating microglial activity through the upregulation of PPARγ, TAK1/IKK/NF-κB, and JNK/p38 MAPK signaling pathways. CONCLUSION: This study indicates that ICA possesses multiple beneficial effects in AD treatment. Through the integration of pharmacological and molecular biological research, ICA may emerge as a promising candidate to expedite the advancement of TCM in the clinical management of AD.

Tailoring particle size of PbI2 towards efficient perovskite solar cells under ambient air conditions.

PbI2 films as templates are essential to the quality of perovskite (PVK) film in a two-step sequential deposition process. Herein, we demonstrate that PbI2 microcrystal powder (P-PbI2) of micrometer size is beneficial for preparing higher-quality PbI2 films in contrast to millimeter-sized PbI2 crystals (C-PbI2) under low relative humidity (RH) conditions. Surprisingly, C-PbI2 allowed the growth of denser films than P-PbI2 under heavy RH conditions. Ultimately, P-PbI2 gave PVK solar cells (PSCs) a best power conversion efficiency (PCE) of 23.30% under a low RH of 30 ± 5%, and C-PbI2 derived an impressive PCE of 21.09% when fabricated under conditions with RH = 50 ± 5%. This work provides ideas for the selection of lead iodide for the fabrication of PSCs under air conditions.

Anterior superior iliac spine distraction for severe and recalcitrant diabetic foot ulcers.

PURPOSE: The study aimed to introduce anterior superior iliac spine distraction to treat severe and recalcitrant diabetic foot ulcers. For comparison, we also included another group of diabetic foot ulcers treated with proximal tibial cortex transverse distraction. METHODS: From February 1998 to February 2020, 87 patients (87 feet) with severe and recalcitrant diabetic foot ulcers were treated. The mean age of patients at surgery was 64 years (range, 47 to 87 years). The severity of the narrowed artery was assessed using the ankle-brachial index test. For comparison, another group of 91 patients (91 diabetic foot ulcers) treated with proximal tibial cortex transverse distraction was included. RESULTS: The mean preoperative ankle-brachial indexes of the two groups were 0.41±0.07 and 0.39±0.05 (OR 0.65 [95% CI -0.77 to 1.58]; P=0.62), respectively. The mean preoperative limb pain was 3.42±2.84 cm and 3.52±3.11 cm (OR 1.54 [95% CI -077 to 1.35]; P=0.083), respectively. At the 2-year follow-up visit, ulcers healed in 72 (83%) and 74 (81%) patients, respectively (P=0.188). The mean postoperative limb pain was 0.52±0.23 cm and 0.49±0.41 cm (OR 2.32 [95% CI -0.27 to 1.66]; P=0.078), respectively. Pin-site infection occurred in 2 patients and 8 patients (P=0.09), respectively. Ulcer recurrence occurred in 13 (15%) patients and 15 (16%) patients (P=0.205), respectively. CONCLUSIONS: Anterior superior iliac spine transverse distraction may be an effective alternative treatment for severe and recalcitrant diabetic foot ulcers. It may be associated with fewer distraction-site complications than proximal tibial cortex transverse distraction. LEVEL OF EVIDENCE: Therapeutic study, Level IIa.

An Intelligent Waste-Sorting and Recycling Device Based on Improved EfficientNet.

The main source of urban waste is the daily life activities of residents, and the waste sorting of residents' waste is important for promoting economic recycling, reducing labor costs, and protecting the environment. However, most residents are unable to make accurate judgments about the categories of household waste, which severely limits the efficiency of waste sorting. We have designed an intelligent waste bin that enables automatic waste sorting and recycling, avoiding the extensive knowledge required for waste sorting. To ensure that the waste-classification model is high accuracy and works in real time, GECM-EfficientNet is proposed based on EfficientNet by streamlining the mobile inverted bottleneck convolution (MBConv) module, introducing the efficient channel attention (ECA) module and coordinate attention (CA) module, and transfer learning. The accuracy of GECM-EfficientNet reaches 94.54% and 94.23% on the self-built household waste dataset and TrashNet dataset, with parameters of only 1.23 M. The time of one recognition on the intelligent waste bin is only 146 ms, which satisfies the real-time classification requirement. Our method improves the computational efficiency of the waste-classification model and simplifies the hardware requirements, which contributes to the residents' waste classification based on intelligent devices.

Thiuram Monosulfide with Ultrahigh Redox Activity Triggered by Electrochemical Oxidation.

Organosulfides are promising cathodes for lithium batteries but often suffer from sluggish kinetics and low cycle stability. Herein, we report an electron-deficient organosulfide (ED-OS), which is formed via electrochemical oxidation of thiuram monosulfide, a low-cost sustainable material. The ED structure of (dimethylcarbamothioyl)thio can stretch the electron cloud of the adjacent C═S bond forming an S radical and lead to the cleavage of the S-C bond on the other side forming another S radical. The two (dimethylcarbamothioyl)thio radicals can form S-S bonds individually with low energy barriers, which thus are easy to break and could accommodate lithium ions with ultrafast reaction kinetics. It exhibits an ultralong cyclability of over 8000 cycles with a low capacity-fade rate of 0.0038% per cycle at a high rate of 10C in a lithium cell. In addition, we demonstrate that the same electrochemical oxidation can be applied to other thiuram compounds. This work provides new opportunities in developing ultrahigh-redox-activity organic electrode materials which can be started as needed.

Efficacy of atosiban combined with ritodrine in the treatment of threatened preterm labor and related risk factors of different pregnancy outcomes.

OBJECTIVE: To investigate the efficacy of atosiban combined with ritodrine in threatened preterm labor (TPL) treatment and analysis of related risk factors of different pregnancy outcomes. METHODS: A retrospective study was conducted on the clinical data of 127 patients with TPL who were hospitalized in the Children's Hospital of Shanxi and Women's Health Center of Shanxi from January 2020 to November 2021. There from, 58 patients treated with ritodrine were seen as the control group (CG), and 69 treated with atosiban and ritodrine were regarded as the joint group (JG). The inhibition rate after treatment was compared, and the changes of tissue inhibitor of metalloproteinase-1 (TIMP-1), nitric oxide (NO), interleukin-6 (IL-6), and prostaglandin E2 (PGE2) in the amniotic fluid before and after treatment were assessed. The pregnancy outcomes of patients were recorded, and the risk factors of adverse pregnancy outcomes were analyzed. The full-term delivery rate, cesarean section rate and neonatal Apgar score >7 were compared, and their adverse reactions were evaluated. RESULTS: Compared with the JG, the improvement of uterine contraction in the CG was obviously lower, and so was the inhibition rate (P<0.05). The rates of full-term delivery and neonatal Apgar score >7 in the CG were lower than those in the JG, while that of cesarean section was higher (P<0.01). After treatment, the TIMP-1 level in the amniotic fluid in the CG was markedly lower (P<0.001), while the NO, IL-6 and PGE2 levels were higher (P<0.001) as compared with the joint group. The total incidence of adverse reactions in the JG was lower than that in the CG (P<0.05). Logistics regression analysis revealed that age<26 and use of Atosiban combined with Ritodrine are protective factors for pregnancy outcomes, while BMI≥20 before pregnancy is a risk factor for adverse pregnancy. CONCLUSION: Atosiban combined with ritodrine can improve the condition of TPL patients, enhance the treatment efficacy, and reduce the occurrence of adverse pregnancy outcomes.

Biomarker Assessment of Homologous Recombination Deficiency in Epithelial Ovarian Cancer: Association With Progression-Free Survival After Surgery.

Identifying BRCA mutations and homologous recombination deficiency (HRD) is the key to choosing patients for poly (ADP-ribose) polymerase inhibitor (PARPi) therapy. At present, a large amount of research focuses on the application of HRD detection in ovarian cancer. However, few studies have discussed the relationship between HRD detection and postoperative survival in patients with epithelial ovarian cancer (EOC). This study included 38 consecutive patients with EOC who underwent cytoreduction surgery. Owing to tissue availability, only 29 patients underwent molecular profiling and survival analysis. Overall, 21 (72.4%) tumors had HRD scores of ≥42. Mutations in BRCA were observed in 5/29 (17.2%) patients. In this cohort, an HRD score of ≥42 was more common in serous ovarian tumors. We found no statistically significant association between homologous recombination repair (HRR) genes and HRD scores except for tumor protein P53 (TP53) mutation. We also found a strong positive association between HRD scores and chromosomal instability (CIN). In the survival analysis, an HRD score of >23 was correlated with better postoperative progression-free survival (pPFS). With increased depth of research, an appropriate HRD score threshold may serve as a prognostic tool and should be assessed in future studies to predict the clinical value of PARPi.

Enhanced thermal transportation across an electrostatic self-assembly of black phosphorene and boron nitride nanosheets in flexible composite films.

For effective heat dissipation in portable electronics, there is a great demand for lightweight and flexible films with superior thermal transport properties. Despite extensive efforts, enhancing the intrinsic low thermal conductivity of polymers while simultaneously maintaining their flexibility is difficult to achieve due to the dilemma of quarrying appropriate filler loading. Herein, a cellulose nanofiber-based film with high in-plane thermal conductivity up to 72.53 W m-1 K-1 was obtained by harnessing the advantage of functionalized boron nitride nanosheets (f-BNNS) and black phosphorene (BP) via the vacuum filtration process. Besides, our unique design based on the electrostatic coupling of black phosphorene and functionalized boron nitride nanosheets significantly reduced the interfacial thermal resistance of the composite films. This work offers new insights into establishing a facile, yet efficient approach to preparing high thermal conductive heat spreaders.

The expressions of matrix metalloproteinase-9, estrogen receptor, and progesterone receptor in thin endometrial tissue and their significance.

OBJECTIVE: This study aims to investigate the expressions of matrix metalloproteinase-9 (MMP-9), estrogen receptor (ER), and progesterone receptor (PR) in thin endometrium. METHODS: Patients who received treatment in our hospital between January 2018 and September 2020 were enrolled. Endometrial thickness was measured using transvaginal ultrasound; in patients with a midluteal phase endometrial thickness of <7 mm, a sample of endometrial tissue was obtained using a hysteroscope, and the MMP-9, ER, and PR expressions were detected using immunohistochemistry. In addition, the number of endometrial glands was calculated in a complete field of view under a low-power (100×) microscope, and the serum estrogen and progesterone levels were determined. Following hormone therapy, the midluteal phase endometrial thickness was measured again using transvaginal ultrasound, and the patients were divided into two groups: the thin endometrium group and the normal endometrium group (n = 50, each). Patients in the thin endometrium group had an endometrial thickness of <7 mm, while patients in the normal endometrium group had an endometrial thickness of 7-10 mm. RESULTS: The number of endometrial glands as well as the ER and MMP-9 expressions were lower in the thin endometrium group than in the normal endometrium group; the differences were statistically significant (p < .05). The receiver operator characteristic curve revealed that ER and MMP-9 had a high prediction accuracy in patients with refractory thin endometrium, while the number of endometrial glands was moderately predictive. CONCLUSION: Compared with other patients with thin endometrium, patients with refractory thin endometrium had a reduced the number of endometrial glands and significantly lower ER and MMP-9 expressions.

Major episodes of horizontal gene transfer drove the evolution of land plants.

How horizontal gene transfer (HGT) has contributed to the evolution of animals and plants remains a major puzzle. Despite recent progress, defining the overall scale and pattern of HGT events in land plants has been largely elusive. In this study, we performed systematic analyses for acquired genes in different plant groups and throughout land plant evolution. We found that relatively recent HGT events occurred in charophytes and all major land plant groups, but their frequency declined rapidly in seed plants. Two major episodes of HGT events occurred in land plant evolution, corresponding to the early evolution of streptophytes and the origin of land plants, respectively. Importantly, a vast majority of the genes acquired in the two episodes have been retained in descendant groups, affecting numerous activities and processes of land plants. We analyzed some of the acquired genes involved in stress responses, ion and metabolite transport, growth and development, and specialized metabolism, and further assessed the cumulative effects of HGT in land plants.

Validation of the hepatocellular carcinoma early detection screening algorithm Doylestown and aMAP in a cohort of Chinese with cirrhosis.

BACKGROUND: Previous studies have developed some blood-based biomarker algorithms such as the Doylestown algorithm and aMAP score to improve the detection of Hepatocellular carcinoma (HCC). However, no one has studied the application of the Doylestown algorithm in the Chinese. Meanwhile, which of these two screening models is more suitable for people with liver cirrhosis remains to be investigated. METHODS: In this study, HCC surveillance was performed by radiographic imaging and testing for tumor markers every 6 months from August 21, 2018, to January 12, 2021. We conducted a retrospective study of 742 liver cirrhosis patients, and among them, 20 developed HCC during follow-up. Samples from these patients at three follow-up time points were tested to evaluate alpha-fetoprotein (AFP), the Doylestown algorithm, and aMAP score. RESULTS: Overall, 521 liver cirrhosis patients underwent semiannual longitudinal follow-up three times. Five patients were diagnosed with HCC within 0-6 months of the third follow-up. We found that for these liver cirrhosis patients, the Doylestown algorithm had the highest accuracy for HCC detection, with areas under the receiver operating characteristic curve (AUCs) of 0.763, 0.801, and 0.867 for follow-ups 1-3, respectively. Compared with AFP at 20 ng/ml, the Doylestown algorithm increased biomarker performance by 7.4%, 21%, and 13% for follow-ups 1-3, respectively. CONCLUSIONS: Our findings show that the Doylestown algorithm performance appeared to be optimal for HCC early screening in the Chinese cirrhotic population when compared with the aMAP score and AFP at 20 ng/ml.

Resistance and fitness costs in diamondback moths after selection using broflanilide, a novel meta-diamide insecticide.

The diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Plutellidae) is an insect pest found around the world that feeds on cruciferous crops. The DBM has become resistant to most insecticides in current use in the field. Broflanilide is a novel meta-diamide insecticide that binds to a new site on the γ-aminobutyric acid receptor and very efficiently protects against most pests in the order Lepidoptera, including DBM. In this study, the resistance of a laboratory-bred susceptible strain of DBM to broflanilide and the fitness costs posed by broflanilide to the DBM were evaluated. The DBM had no obvious resistance to broflanilide after 10 generations of selection. The realized heritability h2 was 0.033, suggesting a low risk of resistance developing in this strain. The F10 generation had no cross-resistance to the insecticides abamectin and endosulfan (which target the γ-aminobutyric acid receptor) and chlorantraniliprole (which targets a non-γ-aminobutyric acid receptor). The specific activities of important detoxification enzymes (cytochrome P450 monooxygenase, esterase, and glutathione S-transferase) were not obviously altered. However, the larval stage was prolonged and the adult stage was shortened significantly in F11 generation than the F0 generation. The total preoviposition period TPOP significantly prolonged 1.90 d in F11 generation. The fitness value Rf (0.93) was lower for the F11 generation than the F0 generation. The results indicated that long-term exposure to broflanilide exerts clear fitness costs in the DBM. This information will be useful in identifying reasonable broflanilide application guidelines for managing broflanilide resistance in the DBM.

Constructing a three-dimensional nano-crystalline diamond network within polymer composites for enhanced thermal conductivity.

In order to meet the requirement of thermal performance with the rapid development of high-performance electronic devices, constructing a three-dimensional thermal transport skeleton is an effective method for enhancing the thermal conductivity of polymer composites. In this work, a three-dimensional porous diamond framework was prepared by depositing nano-crystalline diamond on alumina foam which was impregnated with epoxy to obtain a nano-crystalline diamond@alumina foam/epoxy composite. The epoxy composite with nano-crystalline diamond@alumina foam demonstrated a thermal conductivity of 2.21 W m-1 K-1, which was increased by 1063% in comparison with pure epoxy. The thermal conductivity of the epoxy composite measured under various conditions and heat transport applications demonstrates that it possesses excellent thermal transportation and stability properties. This work provides a new idea to significantly enhance the thermal transportation properties of epoxy composites in the application of advanced packaging materials.

Enhanced Thermal Conductivity of Polymer Composite by Adding Fishbone-like Silicon Carbide.

The rapid development of chip technology has all put forward higher requirements for highly thermally conductive materials. In this work, a new type of material of Fishbone-like silicon carbide (SiC) material was used as the filler in a polyvinylidene fluoride (PVDF) matrix. The silicon carbide/polyvinylidene fluoride (SiC/PVDF) composites were successfully prepared with different loading by a simple mixing method. The thermal conductivity of SiC/PVDF composite reached 0.92 W m-1 K-1, which is 470% higher than that of pure polymer. The results show that using the filler with a new structure to construct thermal conductivity networks is an effective way to improve the thermal conductivity of PVDF. This work provides a new idea for the further application in the field of electronic packaging.

Analysis and Intervention of Factors Affecting Abnormal Postpartum Glucose Tolerance and Gestational Recurrence in Gestational Diabetes.

ObjectiveTo investigate the influencing factors of abnormal postpartum glucose tolerance and pregnancy recurrence in gestational diabetes mellitus (GDM) and to develop reasonable interventions to prevent postpartum glucose tolerance and recurrence of pregnancy. Methods. Retrospective analysis of clinical data of 238 GDM patients during pregnancy, including age, body mass index (BMI) before and after pregnancy, regular exercise during pregnancy, insulin use, family history of diabetes, fasting blood glucose (FPG) during pregnancy, oral glucose tolerance test (OGTT) 2 h time value, blood lipid index, and whether pregnant again. At the same time, the women were followed up by telephone or home visits to understand and guide the patient's diet and exercise. The clinical characteristics of the two groups of patients were compared. According to the OGTT test, the recovery of glucose tolerance in pregnant women 6-8 weeks postpartum was divided into the normal postpartum glucose tolerance group and the abnormal group. Logistic multivariate analysis was used to find the influencing factors of postpartum glucose tolerance and recurrence of pregnancy. Results. Between 238 patients of followed-up, 150 pregnant women had abnormal postpartum glucose tolerance, accounting for 63.03%. There were 115 repregnants, of whom 37 (32.17%) had a recurrence of postpartum glucose tolerance. Pre and postpregnancy BMI, insulin use during pregnancy, family history of diabetes, FPG during pregnancy, OGTT 2 h values, and triglyceride (TG) were independent risk factors for abnormal postpartum diabetes and recurrence of pregnancy in GDM patients. Conclusions. Patients with GDM are at high risk of postpartum abnormal glucose tolerance and pregnancy recurrence, which may be influenced by the pregnant woman's prepregnancy and postpartum BMI, insulin use during pregnancy, family history of diabetes, FPG, OGGT 2 h values during pregnancy, and TG levels. Therefore, health education for pregnant women should be strengthened in the clinic, with guidance on proper diet for weight control, increased exercise, and regular blood glucose screening and monitoring for those at risk.

Regulation of GSTu1-mediated insecticide resistance in Plutella xylostella by miRNA and lncRNA.

The evolution of resistance to insecticides is well known to be closely associated with the overexpression of detoxifying enzymes. Although the role of glutathione S-transferase (GST) genes in insecticide resistance has been widely reported, the underlying regulatory mechanisms are poorly understood. Here, one GST gene (GSTu1) and its antisense transcript (lnc-GSTu1-AS) were identified and cloned, and both of them were upregulated in several chlorantraniliprole-resistant Plutella xylostella populations. GSTu1 was confirmed to be involved in chlorantraniliprole resistance by direct degradation of this insecticide. Furthermore, we demonstrated that lnc-GSTu1-AS interacted with GSTu1 by forming an RNA duplex, which masked the binding site of miR-8525-5p at the GSTu1-3'UTR. In summary, we revealed that lnc-GSTu1-AS maintained the mRNA stability of GSTu1 by preventing its degradation that could have been induced by miR-8525-5p and thus increased the resistance of P. xylostella to chlorantraniliprole. Our findings reveal a new noncoding RNA-mediated pathway that regulates the expression of detoxifying enzymes in insecticide-resistant insects and offer opportunities for the further understanding of the mechanisms of insecticide and drug resistance.

A Green Lead Recycling Strategy from Used Lead Acid Batteries for Efficient Inverted Perovskite Solar Cells.

Lead is widely used as a crucial elemental for lead acid batteries (LABs) and emerging halide perovskite solar cells (PSCs). However, the use of soluble lead will raise environmental concerns. For the purpose of Pb recycling, herein, we report a reactant-recycling strategy to extract Pb from used LABs and synthesize high-purity PbI2. The recycled PbI2 shows smaller grain size, higher crystallinity, and higher thermal stability compared to the commercial sources. Perovskite films deposited with the high-quality PbI2 show larger grain size and fewer defects than the commercial ones. Consequently, the synthesized PbI2 enables a power conversation efficiency of 20.45% for the inverted MAPbI3 (MA= methylammonium) PSCs with excellent air stability. This work offers a novel strategy for lead recovery from LABs and a green path for the realization of high-performance PSCs with high defect tolerance.