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Architecting grain crystallographic orientation can modulate charge distribution and chemomechanical properties for enhancing the performance of polycrystalline battery materials. However, probing the interplay between charge distribution, grain crystallographic orientation, and performance remains a daunting challenge. Herein, we elucidate the spatially resolved charge distribution in lithium layered oxides with different grain crystallographic arrangements and establish a model to quantify their charge distributions. While the holistic “surface-to-bulk” charge distribution prevails in polycrystalline particles, the crystallographic orientation-guided redox reaction governs the charge distribution in the local charged nanodomains. Compared to the randomly oriented grains, the radially aligned grains exhibit a lower cell polarization and higher capacity retention upon battery cycling. The radially aligned grains create less tortuous lithium ion pathways, thus improving the charge homogeneity as statistically quantified from over 20 million nanodomains in polycrystalline particles. This study provides an improved understanding of the charge distribution and chemomechanical properties of polycrystalline battery materials. The authors here report on the influence of grain orientation on the charge distribution in polycrystalline materials for batteries. The quantitative characterization provides mechanistic insight into the way the grain orientation can be engineered to mitigate the charge heterogeneity.

Oxide semiconductors are key materials in many technologies from flat‐panel displays，solar cells to transparent electronics. However, many potential applications are hindered by the lack of high mobility p‐type oxide semiconductors due to the localized O‐2p derived valence band (VB) structure. In this work, the VB structure modulation is reported for perovskite Ba2BiMO6 (M = Bi, Nb, Ta) via the Bi 6s2 lone pair state to achieve p‐type oxide semiconductors with high hole mobility up to 21 cm2 V−1 s−1, and optical bandgaps widely varying from 1.5 to 3.2 eV. Pulsed laser deposition is used to grow high quality epitaxial thin films. Synergistic combination of hard x‐ray photoemission, x‐ray absorption spectroscopies, and density functional theory calculations are used to gain insight into the electronic structure of Ba2BiMO6. The high mobility is attributed to the highly dispersive VB edges contributed from the strong coupling of Bi 6s with O 2p at the top of VB that lead to low hole effective masses (0.4–0.7 me). Large variation in bandgaps results from the change in the energy positions of unoccupied Bi 6s orbital or Nb/Ta d orbitals that form the bottom of conduction band. P–N junction diode constructed with p‐type Ba2BiTaO6 and n‐type Nb doped SrTiO3 exhibits high rectifying ratio of 1.3 × 104 at ±3 V, showing great potential in fabricating high‐quality devices. This work provides deep insight into the electronic structure of Bi3+ based perovskites and guides the development of new p‐type oxide semiconductors. The development of high mobility p‐type oxide is crucial for many technologies including flat‐panel displays, solar cells, and transparent electronics. In this work, the development is reported of novel p‐type oxide semiconductors Ba2BiMO6 (M = Bi, Nb, Ta) with high hole mobility up to 21 cm2 V−1 s−1, and variable bandgaps from 1.5 to 3.2 eV by modulating their VB structure via the Bi 6s2 lone pair states.

Cathode electrolyte interphase (CEI) has a significant impact on the performance of rechargeable batteries and is gaining increasing attention. Understanding the fundamental and detailed CEI formation mechanism is of critical importance for battery chemistry. Herein, a diverse of characterization tools are utilized to comprehensively analyze the composition of the CEI layer as well as its formation mechanism by LiCoO2 (LCO) cathode. We reveal that CEI is mainly composed of the reduction products of electrolyte and it only parasitizes the degraded LCO surface which has transformed into a disordered spinel structure due to oxygen loss and lithium depletion. Based on the energy diagram and the chemical potential analysis, the CEI formation process has been well explained, and the proposed CEI formation mechanism is further experimentally validated. This work highlights that the CEI formation process is nearly identical to that of the anode‐electrolyte‐interphase, both of which are generated due to the electrolyte directly in contact with the low chemical potential electrode material. This work can deepen and refresh our understanding of CEI. Cycling induced surface degradation changes the composition and structure of LiCoO2 surface as well as the electron energy levels, making the surface degradation layer out of the stability window of electrolyte, which in turn causes electrolyte reduction and the formation of cathode electrolyte interphase during battery discharge.

Folate (vitamin B9) is the coenzyme involved in one-carbon transfer biochemical reactions essential for cell survival and proliferation, with its inadequacy causing developmental defects or severe diseases. Notably, mammalian cells lack the ability to de novo synthesize folate but instead rely on its intake from extracellular sources via specific transporters or receptors, among which SLC19A1 is the ubiquitously expressed one in tissues. However, the mechanism of substrate recognition by SLC19A1 remains unclear. Here we report the cryo-EM structures of human SLC19A1 and its complex with 5-methyltetrahydrofolate at 3.5–3.6 Å resolution and elucidate the critical residues for substrate recognition. In particular, we reveal that two variant residues among SLC19 subfamily members designate the specificity for folate. Moreover, we identify intracellular thiamine pyrophosphate as the favorite coupled substrate for folate transport by SLC19A1. Together, this work establishes the molecular basis of substrate recognition by this central folate transporter.

p-Si/n-β-Ga 2 O 3 :Nb heterojunctions were fabricated by RF magnetron sputtering of β-Ga 2 O 3 :Nb layers on the p-Si substrates. The effects of annealing and Nb doping on the properties of heterojunctions were studied. The crystallinity of the β-Ga 2 O 3 :Nb film was enhanced by annealing, which also improved the electrical properties of the heterojunctions. The Nb doping greatly affected the I – V characteristics of annealed heterojunctions. The ideality factor was calculated by performing plots from the forward bias I–V characteristics. The charge transport properties of the heterojunction were discussed. The activation energy of β-Ga 2 O 3 :Nb films were estimated based on the temperature dependence of resistance.

Architecting grain crystallographic orientation can modulate charge distribution and chemomechanical properties for enhancing the performance of polycrystalline battery materials. However, probing the interplay between charge distribution, grain crystallographic orientation, and performance remains a daunting challenge. Herein, we elucidate the spatially resolved charge distribution in lithium layered oxides with different grain crystallographic arrangements and establish a model to quantify their charge distributions. While the holistic \"surface-to-bulk\" charge distribution prevails in polycrystalline particles, the crystallographic orientation-guided redox reaction governs the charge distribution in the local charged nanodomains. Compared to the randomly oriented grains, the radially aligned grains exhibit a lower cell polarization and higher capacity retention upon battery cycling. The radially aligned grains create less tortuous lithium ion pathways, thus improving the charge homogeneity as statistically quantified from over 20 million nanodomains in polycrystalline particles. This study provides an improved understanding of the charge distribution and chemomechanical properties of polycrystalline battery materials

Oxide semiconductors are key materials in many technologies from flat‐panel displays，solar cells to transparent electronics. However, many potential applications are hindered by the lack of high mobility p‐type oxide semiconductors due to the localized O‐2p derived valence band (VB) structure. In this work, the VB structure modulation is reported for perovskite Ba 2 Bi M O 6 ( M = Bi, Nb, Ta) via the Bi 6s 2 lone pair state to achieve p‐type oxide semiconductors with high hole mobility up to 21 cm 2 V −1 s −1 , and optical bandgaps widely varying from 1.5 to 3.2 eV. Pulsed laser deposition is used to grow high quality epitaxial thin films. Synergistic combination of hard x‐ray photoemission, x‐ray absorption spectroscopies, and density functional theory calculations are used to gain insight into the electronic structure of Ba 2 Bi M O 6 . The high mobility is attributed to the highly dispersive VB edges contributed from the strong coupling of Bi 6s with O 2p at the top of VB that lead to low hole effective masses (0.4–0.7 m e ). Large variation in bandgaps results from the change in the energy positions of unoccupied Bi 6s orbital or Nb/Ta d orbitals that form the bottom of conduction band. P–N junction diode constructed with p‐type Ba 2 BiTaO 6 and n‐type Nb doped SrTiO 3 exhibits high rectifying ratio of 1.3 × 10 4 at ±3 V, showing great potential in fabricating high‐quality devices. This work provides deep insight into the electronic structure of Bi 3+ based perovskites and guides the development of new p‐type oxide semiconductors.

Folate (vitamin B9) is the coenzyme involved in one-carbon transfer biochemical reactions essential for cell survival and proliferation, with its inadequacy causing developmental defects or severe diseases. Notably, mammalian cells lack the ability to de novo synthesize folate but instead rely on its intake from extracellular sources via specific transporters or receptors, among which SLC19A1 is the ubiquitously expressed one in tissues. However, the mechanism of substrate recognition by SLC19A1 has been unclear. Here we report the cryo-EM structures of human SLC19A1 and its complex with 5-methyltetrahydrofolate at 3.5-3.6 Å resolution and elucidate the critical residues for substrate recognition. In particular, we reveal that two variant residues among SLC19 subfamily members would designate the specificity for folate. Moreover, we identify intracellular thiamine pyrophosphate as the favorite coupled substrate for folate transport by SLC19A1. Together, this work has established the molecular basis of substrate recognition by this central folate transporter.

Dongxin Lin, Philip Taylor, Li-Dong Wang and colleagues have now pooled three genome-wide association analyses of esophageal squamous cell carcinoma, finding two new risk loci at genome-wide significance and an HLA class II locus of significance in high-risk populations. They reanalyze the strength of evidence for previously published risk loci. We conducted a joint (pooled) analysis of three genome-wide association studies (GWAS) 1 , 2 , 3 of esophageal squamous cell carcinoma (ESCC) in individuals of Chinese ancestry (5,337 ESCC cases and 5,787 controls) with 9,654 ESCC cases and 10,058 controls for follow-up. In a logistic regression model adjusted for age, sex, study and two eigenvectors, two new loci achieved genome-wide significance, marked by rs7447927 at 5q31.2 (per-allele odds ratio (OR) = 0.85, 95% confidence interval (CI) = 0.82–0.88; P = 7.72 × 10 −20 ) and rs1642764 at 17p13.1 (per-allele OR = 0.88, 95% CI = 0.85–0.91; P = 3.10 × 10 −13 ). rs7447927 is a synonymous SNP in TMEM173 , and rs1642764 is an intronic SNP in ATP1B2 , near TP53 . Furthermore, a locus in the HLA class II region at 6p21.32 (rs35597309) achieved genome-wide significance in the two populations at highest risk for ESSC (OR = 1.33, 95% CI = 1.22–1.46; P = 1.99 × 10 −10 ). Our joint analysis identifies new ESCC susceptibility loci overall as well as a new locus unique to the population in the Taihang Mountain region at high risk of ESCC.

Wetting and drying cycles (WDCs) have a significant impact on the shear behavior of discontinuities with different joint wall materials (DDJMs). This influence is crucial for the reasonable evaluation of the long-term stability of soft and hard interbedded rock slopes under water level fluctuations. As the surface topographies of natural discontinuities collected from the field vary, conducting comparative experiments on natural discontinuity specimens with identical surface topographies is challenging. To solve this problem, a 3D surface topography reconstruction technique was employed to obtain DDJM specimens with three types of surface topographies collected from a typical sliding-prone stratum in the Three Gorges Reservoir area, China. A series of experiments, including computed tomography scanning, 3D laser scanning, and direct shear tests, were conducted to investigate the influence of WDCs on the micro- and macroproperties of joint walls, surface topographies, and shear behavior of DDJMs. The experimental results showed that repeated WDC treatments caused the degradation of the microstructures and macroscopic physical properties of the studied joint walls, and the more severely weakened joint wall played a predominant role in reducing the shear strength of DDJMs. The influence of WDCs on the surface topographies of DDJMs was negligible in this study; changes in the shear behavior of DDJMs were closely associated with the weakening of joint walls induced by WDCs; and the impact degree of joint wall weakening on the deterioration of the shear behavior of DDJMs was interactively influenced by and positively correlated with both the joint roughness coefficient and normal stress. These results will contribute to a better understanding of the evolution of the stability of soft and hard interbedded rock slopes induced by water level fluctuations in the Three Gorges Reservoir area and other reservoir regions.