Unraveling the Influence of Solvent on Side Reactions between Formamidinium Lead Triiodide and Methylammonium Cations.

Formamidinium lead triiodide (FAPbI3) perovskite thin films are commonly deposited through a solution process, often incorporating a specific amount of methylammonium halide to stabilize the α-phase or enhance their crystallinity. The precursor solution for such coatings significantly influences the fabrication of perovskite solar cells (PSCs), involving time-dependent aging and byproduct formation. The chemical principle underlying this behavior is believed to be related to the deprotonation of methylamine cations (MA+) and subsequent chemical reactions with FA+ to generate N-methylformamidinium. Nevertheless, the role of the solvent in the side reactions between these organic cations remains unclear. This work systematically investigates the reaction reactivity in three protic solvents and three aprotic solvents. We uncover the hidden role of dimethylamine from the hydrolysis products of N,N-dimethylformamide, promoting the reaction between FA+ and MA+. Additionally, we elucidate the impact of environmental factors, such as water and oxygen, in stabilizing precursor solutions. This work establishes a basic concept and scientific direction for rationalizing high-efficiency, reproducible, and long-term-stable PSCs.

Deciphering Reaction Products in Formamidine-Based Perovskites with Methylammonium Chloride Additive.

The fabrication of formamidinium lead iodide (FAPbI3) perovskite solar cells (PSCs) involves the addition of methylammonium chloride (MACl) to promote low-temperature α-phase formation and grain growth. However, as the added MACl deprotonates and volatilizes into methylamine (MA0) and HCl for removal, MA0 can chemically interact with formamidinium (FA+), forming methyl formamidinium (MFA+) as a byproduct. Despite its significance, the chemical interactions among FAPbI3 perovskites, MACl additives, and their byproducts remain poorly understood. Our findings reveal that the FA+ and MA0 reaction primarily yields a mixture of cis/trans-N-methyl formamidinium iodide (MFAI) isomers, with cis-MFAI prevailing as the dominant species. Moreover, MFAI subsequently reacts with PbI2 to yield fully formed cis-MFAPbI3 2H-phase perovskite. We elucidated the effects of MFAI on the crystal growth, phase stability, and band gap of formamidine-based perovskites through the growth of single crystals. This research offers valuable insights into the role of these byproducts in influencing the efficiency and long-term stability of future PSCs.

Integrated System Built for Small-Molecule Semiconductors via High-Throughput Approaches.

High-throughput synthesis of solution-processable structurally variable small-molecule semiconductors is both an opportunity and a challenge. A large number of diverse molecules provide a possibility for quick material discovery and machine learning based on experimental data. However, the diversity of the molecular structure leads to the complexity of molecular properties, such as solubility, polarity, and crystallinity, which poses great challenges to solution processing and purification. Here, we first report an integrated system for the high-throughput synthesis, purification, and characterization of molecules with a large variety. Based on the principle "Like dissolves like," we combine theoretical calculations and a robotic platform to accelerate the purification of those molecules. With this platform, a material library containing 125 molecules and their optical-electronic properties was built within a timeframe of weeks. More importantly, the high repeatability of recrystallization we design is a reliable approach to further upgrading and industrial production.

Knockdown of Long Noncoding RNA Abhd11os Attenuates Myocardial Ischemia/Reperfusion Injury by Inhibiting Apoptosis in Cardiomyocytes.

ABSTRACT: Long noncoding RNA is one potential target for the treatment of various disorders. Here, we explored the role of Abhd11os in ischemia/reperfusion-induced myocardial injury, and preliminarily explored the regulatory mechanisms. Relative Abhd11os expression level was examined by qRT-PCR. Western blot was done to measure the expression of apoptotic-related proteins. Cell counting kit-8 assay and flow cytometry were performed to detect cell viability and apoptosis, respectively. ELISA assay was used to ensure the levels of lactate dehydrogenase, creatine kinase, and cardiac troponin I in serum. Besides, the infarct sizes were confirmed by 2,3,5-triphenyltetrazolium chloride and Evans blue staining. Apoptotic rate of cardiomyocytes in myocardial tissues was evaluated by TUNEL assay. Here, increased Abhd11os expression was found in rat myocardial ischemia/reperfusion injury (MIRI) model and hypoxia/reoxygenation-treated cardiomyocytes. Subsequently, our data in vitro showed that upregulation of Abhd11os inhibited proliferation of cardiomyocytes, but promoted cell apoptosis. In animal experiments, myocardial infarct size in MIRI rats was reduced by Abhd11os knockdown. Moreover, downregulation of Abhd11os inhibited apoptosis of cardiomyocytes. Overall, our results revealed that knockdown of Abhd11os could notably attenuate hypoxia/reoxygenation-induced myocardial injury through suppressing apoptosis of cardiomyocytes. These data suggest that Abhd11os may be a potential target for MIRI therapy.

Transcriptome landscapes of multiple tissues highlight the genes involved in the flavor metabolic pathway in Chinese chive (Allium tuberosum).

The unique flavor of Allium tuberosum is primarily associated with the hydrolysis of a series of organosulfur compounds, S-alk(en)yl cysteine sulphoxides (CSOs), upon tissue bruising or maceration. To obtain the tissue-specific transcriptomes, 18 RNA-Seq libraries representing leaf, root, stem, mature flower, inflorescence, and seed tissues of A. tuberosum were sequenced, finally yielding 133.7 Gb clean reads. The de novo assembled transcriptomes enabled the identification of 223,529 unigenes, which were functionally annotated and analyzed for the gene ontology and metabolic pathways. Furthermore, to reveal the flavor metabolic pathways, a total of 205 unigenes involved in the sulfur assimilation and CSO biosynthesis were identified, and their expression profiles were analyzed by RNA-Seq and qRT-PCR. Collectively, this study provides a valuable resource for in-depth molecular and functional researches especially on flavor formation, as well as for the development of molecular markers, and other genetic studies in A. tuberosum.

Genome-Wide Analysis of Auxin Response Factors in Lettuce (Lactuca sativa L.) Reveals the Positive Roles of LsARF8a in Thermally Induced Bolting.

Warm temperatures induce plant bolting accompanied by flower initiation, where endogenous auxin is dynamically associated with accelerated growth. Auxin signaling is primarily regulated by a family of plant-specific transcription factors, AUXIN RESPONSE FACTORS (ARFs), which either activate or repress the expression of downstream genes in response to developmental and environmental cues. However, the relationship between ARFs and bolting has not been completely understood in lettuce yet. Here, we identified 24 LsARFs (Lactuca sativa ARFs) in the lettuce genome. The phylogenetic tree indicated that LsARFs could be classified into three clusters, which was well supported by the analysis of exon-intron structure, consensus motifs, and domain compositions. RNA-Seq analysis revealed that more than half of the LsARFs were ubiquitously expressed in all tissues examined, whereas a small number of LsARFs responded to UV or cadmium stresses. qRT-PCR analysis indicated that the expression of most LsARFs could be activated by more than one phytohormone, underling their key roles as integrative hubs of different phytohormone signaling pathways. Importantly, the majority of LsARFs displayed altered expression profiles under warm temperatures, implying that their functions were tightly associated with thermally accelerated bolting in lettuce. Importantly, we demonstrated that silencing of LsARF8a, expression of which was significantly increased by elevated temperatures, resulted in delayed bolting under warm temperatures, suggesting that LsARF8a might conduce to the thermally induced bolting. Together, our results provide molecular insights into the LsARF gene family in lettuce, which will facilitate the genetic improvement of the lettuce in an era of global warming.

Intrinsic Phase Stability and Inherent Bandgap of Formamidinium Lead Triiodide Perovskite Single Crystals.

Understanding the intrinsic phase stability and inherent band gap of formamidinium lead triiodide (FAPbI3 ) perovskites is crucial to further improve the performance of perovskite solar cells (PSCs). Herein, we explored the α- to δ-phase transition and band gap of FAPbI3 single crystals grown by an inverse temperature solubility method. We found that the residual γ-butyrolactone solvents in the inner empty space of the FAPbI3 single crystal accelerate the phase transition at kinetics. By adopting 2-methoxyethanol as the solvent, over 2000 h of stable α-FAPbI3 crystals could be acquired. This proves that although FAPbI3 is regarded as unstable at thermodynamics, it could own excellent kinetic stability without any doping or additives because of the slow solid to solid phase transition instead of the fast phase transition assisted by the solvents. Furthermore, we revealed that the bulk FAPbI3 single crystal with a size above 100 µm can have an inherent band gap of 1.41 eV. Thus, our work provides key scientific guidance for high-performance FAPbI3 -based PSCs.

Exploration and validation of hub genes and pathways in the progression of hypoplastic left heart syndrome via weighted gene co-expression network analysis.

BACKGROUND: Despite significant progress in surgical treatment of hypoplastic left heart syndrome (HLHS), its mortality and morbidity are still high. Little is known about the molecular abnormalities of the syndrome. In this study, we aimed to probe into hub genes and key pathways in the progression of the syndrome. METHODS: Differentially expressed genes (DEGs) were identified in left ventricle (LV) or right ventricle (RV) tissues between HLHS and controls using the GSE77798 dataset. Then, weighted gene co-expression network analysis (WGCNA) was performed and key modules were constructed for HLHS. Based on the genes in the key modules, protein-protein interaction networks were conducted, and hub genes and key pathways were screened. Finally, the GSE23959 dataset was used to validate hub genes between HLHS and controls. RESULTS: We identified 88 and 41 DEGs in LV and RV tissues between HLHS and controls, respectively. DEGs in LV tissues of HLHS were distinctly involved in heart development, apoptotic signaling pathway and ECM receptor interaction. DEGs in RV tissues of HLHS were mainly enriched in BMP signaling pathway, regulation of cell development and regulation of blood pressure. A total of 16 co-expression network were constructed. Among them, black module (r = 0.79 and p value = 2e-04) and pink module (r = 0.84 and p value = 4e-05) had the most significant correlation with HLHS, indicating that the two modules could be the most relevant for HLHS progression. We identified five hub genes in the black module (including Fbn1, Itga8, Itga11, Itgb5 and Thbs2), and five hub genes (including Cblb, Ccl2, Edn1, Itgb3 and Map2k1) in the pink module for HLHS. Their abnormal expression was verified in the GSE23959 dataset. CONCLUSIONS: Our findings revealed hub genes and key pathways for HLHS through WGCNA, which could play key roles in the molecular mechanism of HLHS.

Deciphering immunodiffusion: In silico optimization for faster protein diagnostics.

Immunodiffusion tests offer a simple yet powerful method for detecting protein antigens, but their long assay times hinder clinical utility. We unveil the complex interplay of parameters governing this process using finite element simulations. By meticulously validating our model against real-world data, we elucidate how initial concentrations and diffusivities of antigen and antibody shape the intensity, size, and formation time of the precipitin ring. Our key innovation lies in employing phase diagram analysis to map the combined effects of these parameters on assay performance. This framework enables rapid in silico parameter estimation, paving the way for the design of novel immunodiffusion assays with drastically reduced assay times. The presented approach holds immense potential for optimizing protein diagnostics for fast and reliable diagnostics.

Emergence of precursor instabilities in geo-processes: Insights from dense active matter.

We present the hypothesis that investigation of precursor mechanisms to large scale instabilities, that have so far been overlooked in geo-processes, is possible. These precursor processes are evident in multicomponent materials, such as granular matter, when driven far from equilibrium on its microscale. The material is then classified as "dense active matter" with unexpected behaviour by non-local dissipation of internal energy releasing its dynamic incompatibility with the macroscopic gradients as self-excitation waves under external forcing. These instabilities are known in solid mechanics as flutter instabilities, nucleating at what is more widely known as an "exceptional point" in a variety of systems when two or more eigenvalues of the system coalesce. The common principle to connect processes at and across their characteristic scales is investigated using a minimalist formulation by coupling the scalar field variables of solid and fluid pressures in a compacting porous medium. We present a multiphysics generalisation of the phenomenon to the exciting findings of fluctuations with oscillatory exponential growth which nucleate at the exceptional point for inception of complex conjugate eigenmodes and propose a rigorous theory based on the extension of Onsager's theorem to non-local processes. Future work will need to compare model predictions to carefully designed laboratory experiments and expand the work to bridge the scale of the laboratory to the scale of field applications including design of new sensors tuned for detecting exceptional points preceding collapse of materials.

Favorable mid-term performance of fully biodegradable implantable device for ventricular septal defect closure.

Objectives: To assess the mid-term safety and efficacy of transthoracic perimembranous ventricular septal defect (Pm-VSD) closure using a new biodegradable device. Implantation entailed right subaxillary minithoracotomy under transesophageal echocardiography guidance. Methods: Between October 2019 and January 2020, 13 patients (males, 5; mean age, 3.6 ± 2.5 years) with Pm-VSDs underwent transthoracic device closures at Zhengzhou University Central China Fuwai Hospital as described previously. Delivery pathways were established by manipulating a hollow probe from right atrium through tricuspid valve to right ventricle and then through VSDs to left ventricle, whereupon installation took place. Results: All occluder implantations were successfully executed. Mean defect size was 4.1 ± 1.0 mm, and mean device waist size was 5.2 ± 1.1 mm. One patient (7.7%) with 1.5-mm residual shunt showed complete closure at discharge. There was 1 instance of postoperative incomplete right bundle branch block, which converted to complete right bundle branch block at month 1. During patient follow-up (mean, 24.6 ± 0.8 months), no device dislocations, new residual shunts, new valvular regurgitation, or detectable atrioventricular block ensued. Conclusions: Closure of Pm-VSDs using a novel, fully biodegradable occluder in the manner described has proven safe and effective at mid-term follow-up. Long-term safety and efficacy of this device must be further corroborated in a large patient cohort going forward.

Physiological, transcriptomic, and metabolic analyses reveal that mild salinity improves the growth, nutrition, and flavor properties of hydroponic Chinese chive (Allium tuberosum Rottler ex Spr).

Environmental stressors such as salinity have pronounced impacts on the growth, productivity, nutrition, and flavor of horticultural crops, though yield loss sometimes is inevitable. In this study, the salinity influences were evaluated using hydroponic Chinese chive (Allium tuberosum) treated with different concentrations of sodium chloride. The results demonstrated that lower salinity could stimulate plant growth and yield. Accordingly, the contents of soluble sugar, ascorbic acid, and soluble protein in leaf tissues increased, following the decrease of the nitrate content, under mild salinity (6.25 or 12.5 mM NaCl). However, a higher level of salinity (25 or 50 mM NaCl) resulted in growth inhibition, yield reduction, and leaf quality deterioration of hydroponic chive plants. Intriguingly, the chive flavor was boosted by the salinity, as evidenced by pungency analysis of salinity-treated leaf tissues. UPLC-MS/MS analysis reveals that mild salinity promoted the accumulation of glutamic acid, serine, glycine, and proline in leaf tissues, and thereby enhanced the umami and sweet flavors of Chinese chive upon salinity stress. Considering the balance between yield and flavor, mild salinity could conduce to hydroponic Chinese chive cultivation. Transcriptome analysis revealed that enhanced pungency could be ascribed to a salt stress-inducible gene, AtuFMO1, associated with the biosynthesis of S-alk(en)yl cysteine sulphoxides (CSOs). Furthermore, correlation analysis suggested that two transcription factors, AtubHLH and AtuB3, were potential regulators of AtuFMO1 expressions under salinity. Thus, these results revealed the molecular mechanism underlying mild salinity-induced CSO biosynthesis, as well as a practical possibility for producing high-quality Chinese chive hydroponically.

Efficient and Stable Antimony Selenoiodide Solar Cells.

Although antimony selenoiodide (SbSeI) exhibits a suitable bandgap as well as interesting physicochemical properties, it has not been applied to solar cells. Here the fabrication of SbSeI solar cells is reported for the first time using multiple spin-coating cycles of SbI3 solutions on Sb2Se3 thin layer, which is formed by thermal decomposition after depositing a single-source precursor solution. The performance exhibits a short-circuit current density of 14.8 mA cm-2, an open-circuit voltage of 473.0 mV, and a fill factor of 58.7%, yielding a power conversion efficiency (PCE) of 4.1% under standard air mass 1.5 global (AM 1.5 G, 100 mW cm-2). The cells retain ≈90.0% of the initial PCE even after illuminating under AM 1.5G (100 mW cm-2) for 2321 min. Here, a new approach is provided for combining selenide and iodide as anions, to fabricate highly efficient, highly stable, green, and low-cost solar cells.

Efficacy of rapid on-site cytological evaluation (ROSE) by a pulmonologist in determining specimen adequacy and diagnostic accuracy in interventional diagnosis of lung lesions.

OBJECTIVE: To evaluate the efficacy of rapid on-site cytological evaluation (ROSE) in determining specimen adequacy and diagnostic accuracy in the interventional diagnosis of lung lesions. METHODS: This retrospective study included 127 consecutive cases of lung lesions, which were sampled by bronchoscopy or transthoracic fine needle aspiration, and diagnosed on ROSE followed by histopathology. ROSE was performed by a trained pulmonologist and the diagnosis of ROSE was compared with the final diagnosis. RESULTS: The sensitivity of ROSE in determining adequacy of specimens was 97.5% and specificity in determining inadequacy was 85.7%. The diagnostic efficacy of ROSE for assessing malignancy (sensitivity of 94.5% and specificity of 100%) and non-malignancy (sensitivity of 97.8% and specificity of 100%) was excellent. The sensitivity of ROSE for diagnosing small cell carcinoma (100%) was highest, followed by adenocarcinoma (89.2%) and squamous cell carcinoma (75.0%). Performance of ROSE by a trained pulmonologist also determined tuberculosis with a high diagnostic sensitivity (83.3%) and specificity (100%). CONCLUSIONS: A trained pulmonologist can reliably carry out ROSE to ensure the adequacy of the sample, distinguish between malignancy and non-malignancy, and make a preliminary diagnosis in a large number of cases.

Determination of reliable reference genes for gene expression studies in Chinese chive (Allium tuberosum) based on the transcriptome profiling.

Chinese chive (Allium tuberosum) is widely cultivated around the world for its unique flavor, nutrient, and medicinal values, yet its molecular mechanism on flavor formation and other metabolic pathways remains intangible. The elucidation of these complex processes begins with investigating the expression of the genes of interest, however the appropriate reference genes (RGs) for normalizing the gene expression are still unavailable in A. tuberosum. To fill this lacuna, transcriptome-wide screening was undertaken to identify the most stable genes according to the analysis of their FPKM values. The expression stability of the RGs was further evaluated using geNorm, NormFinder, BestKeeper, and RefFinder algorithms. The comprehensive analysis showed that GLY1 and SKP1, instead of two traditionally used RGs (eIF1α and ACT2), were the most stable genes across diverse A. tuberosum tissues, indicating the necessity to carefully validate the stability of RGs prior to their use for normalizations. As indicated by geNorm, the normalizations with at least two RGs could give more accurate results. qRT-PCR experiments were conducted with randomly selected genes, demonstrating that normalization with a combination of GLY1 and SKP1 resulted in reliable normalization results. Our finding represents the first attempt toward establishing a standardized qRT-PCR analysis in this economically important vegetable.

Strain Tuning via Larger Cation and Anion Codoping for Efficient and Stable Antimony-Based Solar Cells.

Strain induced by lattice distortion is one of the key factors that affect the photovoltaic performance via increasing defect densities. The unsatisfied power conversion efficiencies (PCEs) of solar cells based on antimony chalcogenides (Sb-Chs) are owing to their photoexcited carriers being self-trapped by the distortion of Sb2S3 lattice. However, strain behavior in Sb-Chs-based solar cells has not been investigated. Here, strain tuning in Sb-Chs is demonstrated by simultaneously replacing Sb and S with larger Bi and I ions, respectively. Bi/I codoped Sb2S3 cells are fabricated using poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7-(2,1,3-enzothiadiazole)] as the hole-transporting layer. Codoping reduced the bandgap and rendered a bigger tension strain (1.76 × 10-4) to a relatively smaller compression strain (-1.29 × 10-4). The 2.5 mol% BiI3 doped Sb2S3 cell presented lower trap state energy level than the Sb2S3 cell; moreover, this doping amount effectively passivated the trap states. This codoping shows a similar trend even in the low bandgap Sb2(SxSe1-x)3 cell, resulting in 7.05% PCE under the standard illumination conditions (100 mW cm-2), which is one of the top efficiencies in solution processing Sb2(SxSe1-x)3 solar cells. Furthermore, the doped cells present higher humidity, thermal and photo stability. This study provides a new strategy for stable Pb-free solar cells.

Role of metformin in treatment of patients with chronic obstructive pulmonary disease: a systematic review.

Chronic obstructive pulmonary disease (COPD) is commonly associated with type 2 diabetes mellitus (T2DM). Metformin is a first-line treatment for most patients with T2DM, and may have antiaging, antioxidant, and anti-tumour effects. A few published studies report the use of metformin for the treatment of COPD in patients with or without T2DM, but the results are inconsistent. This study aimed to confirm the effectiveness and safety of metformin as a treatment option in patients with COPD. We performed a systematic search of PubMed, EMBASE, and the Cochrane database from their starting date to December 2017. Randomised controlled trials (RCTs), controlled clinical trials, and retrospective researches reporting the use of metformin for treating patients with COPD were identified. We included a total of six articles (involving 3,467 participants) and found that metformin may benefit patients with COPD and T2DM by improving health status and symptoms, hospitalisations, and mortality. There was no effect on patients with COPD without T2DM. Metformin causes minimal increases in plasma lactate concentrations without lactic acidosis and has little impact on blood glucose and minor adverse events. Metformin is safe and effective for treating COPD in patients with concomitant T2DM.

Organic Monomolecular Layers Enable Energy-Level Matching for Efficient Hole Transporting Layer Free Inverted Perovskite Solar Cells.

High-efficiency hole transport layer free perovskite solar cells (HTL-free PSCs) with economical and simplified device structure can greatly facilitate the commercialization of PSCs. However, eliminating the key HTL in PSCs results usually in a severe efficiency loss and poor carrier transfer due to the energy-level mismatching at the indium tin oxide (ITO)/perovskite interface. In this study, we solve this issue by introducing an organic monomolecular layer (ML) to raise the effective work function of ITO with the assistance of an interface dipole created by Sn-N bonds. The energy-level alignment at the ITO/perovskite interface is optimized with a barrier-free contact, which favors efficient charge transfer and suppressed nonradiative carrier recombination. The HTL-free PSCs based on the ML-modified ITO yield an efficiency of 19.4%, much higher than those of HTL-free PSCs on bare ITO (10.26%), comparable to state-of-the-art PSCs with a HTL. This study provides an in-depth understanding of the mechanism of interfacial energy-level alignment and facilitates the design of advanced interfacial materials for simplified and efficient PSC devices.

Side-Chain Polymers as Dopant-Free Hole-Transporting Materials for Perovskite Solar Cells-The Impact of Substituents' Positions in Carbazole on Device Performance.

Side-chain polymers have the potential to be excellent dopant-free hole-transporting materials (HTMs) for perovskite solar cells (PSCs) because of their unique characteristics, such as tunable energy levels, high charge mobility, good solubility, and excellent film-forming ability. However, there has been less research focusing on side-chain polymers for PSCs. Here, two side-chain polystyrenes with triphenylamine substituents on carbazole moieties were designed and characterized. The properties of the side-chain polymers were tuned finely, including the photophysical and electrochemical properties and charge mobilities, by changing the positions of triphenylamine substituents on carbazole. Owing to the higher mobility and charge extraction ability, the polymer P2 with the triphenylamine substituent on the 3,6-positions of the carbazole unit showed higher performance with power conversion efficiency (PCE) of 18.45%, which was much higher than the PCE (16.78%) of P1 with 2,7-positions substituted. These results clearly demonstrated that side-chain polymers can act as promising HTMs for PSC applications and the performance of side-chain polymers could be optimized by carefully tuning the structure of the monomer, which provides a new strategy to design new kinds of side-chain polymers and obtain high-performance dopant-free HTMs.

Evaluation of A-Site Ba2+-Deficient Ba1-x Co0.4Fe0.4Zr0.1Y0.1O3-δ Oxides as Electrocatalysts for Efficient Hydrogen Evolution Reaction.

Exploring earth-abundant and cost-effective catalysts with high activity and stability for a hydrogen evolution reaction (HER) is of great importance to practical applications of alkaline water electrolysis. Here, we report on A-site Ba2+-deficiency doping as an effective strategy to enhance the electrochemical activity of BaCo0.4Fe0.4Zr0.1Y0.1O3-δ for HER, which is related to the formation of oxygen vacancies around active Co/Fe ions. By comparison with the benchmarking Ba0.5Sr0.5Co0.8Fe0.2O3-δ , one of the most spotlighted perovskite oxides, the Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3-δ oxide has lower overpotential and smaller Tafel slope. Furthermore, the Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3-δ catalyst is ultrastable in an alkaline solution. The enhanced HER performance originated from the increased active atoms adjacent to oxygen vacancies on the surface of the Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3-δ catalyst induced by Ba2+-deficiency doping. The low-coordinated active atoms and adjacent oxygen ions may play the role of heterojunctions that synergistically facilitate the Volmer process and thus render stimulated HER catalytic activity. The preliminary results suggest that Ba2+-deficiency doping is a feasible method to tailor the physical and electrochemical properties of perovskite, and that Ba0.95Co0.4Fe0.4Zr0.1Y0.1O3-δ is a potential catalyst for HER.