Neuromorphic computing represents an innovative technology that can perform intelligent and energy-efficient computation, whereas construction of neuromorphic systems requires biorealistic synaptic elements with rich dynamics that can be tuned based on a robust mechanism. Here, an ionic-gating-modulated synaptic transistor based on layered crystals of transitional metal dichalcogenides and phosphorus trichalcogenides is demonstrated, which produce a diversity of short-term and long-term plasticity including excitatory postsynaptic current, paired pulse facilitation, spiking-rate-dependent plasticity, dynamic filtering, etc., with remarkable linearity and ultralow energy consumption of ≈30 fJ per spike. Detailed transmission electron microscopy characterization and ab initio calculation reveal two-stage ionic gating effects, namely, surface adsorption and internal intercalation in the channel medium, causing different poststimulation diffusive dynamics and thus accounting for the observed short-term and long-term plasticity, respectively. The synaptic activity can therefore be effectively manipulated by tailoring the ionic gating and consequent diffusion dynamics with varied thickness and structure of the van der Waals material as well as the number, duration, rate, and polarity of gate stimulations, making the present synaptic transistors intriguing candidates for low-power neuromorphic systems.

We performed a genome-wide association study of esophageal squamous cell carcinoma (ESCC) by genotyping 1,077 individuals with ESCC and 1,733 control subjects of Chinese Han descent. We selected 18 promising SNPs for replication in an additional 7,673 cases of ESCC and 11,013 control subjects of Chinese Han descent and 303 cases of ESCC and 537 control subjects of Chinese Uygur-Kazakh descent. We identified two previously unknown susceptibility loci for ESCC: PLCE1 at 10q23 (P(Han combined for ESCC) = 7.46 x 10(-56), odds ratio (OR) = 1.43; P(Uygur-Kazakh for ESCC) = 5.70 x 10(-4), OR = 1.53) and C20orf54 at 20p13 (P(Han combined for ESCC) = 1.21 x 10(-11), OR = 0.86; P(Uygur-Kazakh for ESCC) = 7.88 x 10(-3), OR = 0.66). We also confirmed association in 2,766 cases of gastric cardia adenocarcinoma cases and the same 11,013 control subjects (PLCE1, P(Han for GCA) = 1.74 x 10(-39), OR = 1.55 and C20orf54, P(Han for GCA) = 3.02 x 10(-3), OR = 0.91). PLCE1 and C20orf54 have important biological implications for both ESCC and GCA. PLCE1 might regulate cell growth, differentiation, apoptosis and angiogenesis. C20orf54 is responsible for transporting riboflavin, and deficiency of riboflavin has been documented as a risk factor for ESCC and GCA.

International audienceThe success of lithium-ion batteries in small-scale applications translates to large-scale applications, with an important impact in the future of the environment by improving energy efficiency and reduction of pollution. In this review, we present the progress that allows lithium-insertion compounds with the spinel structure to become the active cathode element of a new generation of Li-ion batteries, namely the 5 V cathodes, which promise to improve the technologies of energy storage and electric transportation, thereby addressing the replacement of the gasoline engine and the increasing demand for green energy power sources. The compounds considered here include the spinel LiNi0.5Mn1.5O4 and its related Cr-doped structure. Emphasis is placed on the control of physical properties that is needed to guarantee the reliability and the optimum electrochemical performance of these materials as the active cathode element of Li-ion batteries. We also report the structural evolution of the spinel phase in both charge (Li extraction) and discharge (Li insertion) reactions

Recently, intensive efforts are dedicated to convert and store the solar energy in a single device. Herein, dye-synthesized solar cell technology is combined with lithium-ion materials to investigate light-assisted battery charging. In particular we report the direct photo-oxidation of lithium iron phosphate nanocrystals in the presence of a dye as a hybrid photo-cathode in a two-electrode system, with lithium metal as anode and lithium hexafluorophosphate in carbonate-based electrolyte; a configuration corresponding to lithium ion battery charging. Dye-sensitization generates electron–hole pairs with the holes aiding the delithiation of lithium iron phosphate at the cathode and electrons utilized in the formation of a solid electrolyte interface at the anode via oxygen reduction. Lithium iron phosphate acts effectively as a reversible redox agent for the regeneration of the dye. Our findings provide possibilities in advancing the design principles for photo-rechargeable lithium ion batteries.

In liithium–sulfur battery the lithium metal surface was analyzed by in situ Raman spectroscopy.

Enabled by recent advances in symmetry and electronic structure, researchers have observed signatures of unconventional threefold degeneracies in tungsten carbide, challenging a longstanding paradigm in nodal semimetals.

Few-layer ternary FePS3 nanosheets, prepared via chemical vapor transport synthesis and ball-milling exfoliation, exhibit excellent electrocatalytic performance for the oxygen evolution reaction in an alkaline medium. Combined with first principles calculations, our X-ray spectroscopy and HRTEM results clearly reveal that the introduction of in-plane defects in FePS3 layers after exfoliation and formation of a FePS3-FeOOH heterostructure during the OER process largely contribute to the catalytic activity enhancement.

Energy storage with high energy density and low cost has been the subject of a decades-long pursuit. Sodium-ion batteries are well expected because they utilize abundant resources. However, the lack of competent cathodes with both large capacities and long cycle lives prevents the commercialization of sodium-ion batteries. Conventional cathodes with hexagonal-P2-type structures suffer from structural degradations when the sodium content falls below 33%, or when the integral anions participate in gas evolution reactions. Here, we show a “pillar-beam” structure for sodium-ion battery cathodes where a few inert potassium ions uphold the layer-structured framework, while the working sodium ions could diffuse freely. The thus-created unorthodox orthogonal-P2 K0.4[Ni0.2Mn0.8]O2 cathode delivers a capacity of 194 mAh/g at 0.1 C, a rate capacity of 84% at 1 C, and an 86% capacity retention after 500 cycles at 1 C. The addition of the potassium ions boosts simultaneously the energy density and the cycle life.