With rising CO2 emissions caused by the massive consumption of fossil fuels, it is highly desirable to develop strategies that adopt renewable energy to convert CO2 into value‐added chemical ...feedstocks. Over the past decades, photocatalytic reduction of CO2 using light energy has attracted considerable attention. However, the advanced photocatalysis techniques cannot exert their action where light is unavailable. Here, a method for CO2 reduction on basis of vibration‐driven piezoelectricity to yield a piezo‐electrocatalysis effect which requires mechanical vibration rather than light, is proposed. Under mild vibration and sacrificial agent‐free conditions, the piezoelectric BaTiO3 catalyst provides a suitable piezo‐potential to overcome the redox potential of CO2 and convert it into CO with a maximum yield of 63.3 µmol g−1, achieving a reactivity comparable to those of photocatalysts. The piezo‐electrocatalytic CO2 reduction reaction adds a new avenue in addition to the existing photocatalytic techniques by expanding the scope of energy utilization to promote carbon neutrality.
Exploring strategies to expand the sources of natural energy utilization is imperative to cope with ever‐increasing CO2 emissions. A photon‐free piezo‐electrocatalysis system based on the coupling of piezoelectricity and electrochemistry enables the harvesting of dispersed and extensive mechanical energy and converts CO2 into value‐added chemical fuels. The piezo‐electrocatalytic CO2 reduction reaction adds a new avenue to promote carbon neutrality.
Sex differences have been clinically documented in numerous neurodegenerative diseases and yet the reasons for these differences are not well understood. Recent studies have found that microglia, the ...innate immune cells of the central nervous system, are a key cell type involved in neurodegenerative diseases. This cell type displays sex differences in their expression profiles and function. Could these sex differences in microglia explain the sex differences seen in neurodegenerative diseases? How can we further probe these differences to better understand disease mechanisms? In this Opinion, we highlight the recent evidence that microglia have sex differences, factors that contribute to these differences, and how these differences could shed new light on the pathophysiology of neurological diseases.
Recent studies have converged on the importance of neuroinflammatory processes in nonautoimmune neurodegenerative diseases, with a special focus on microglia. Many studies have demonstrated the heterogeneity of this cell type with a diverse number of functions in the brain.One emerging finding is the vast sex differences in the transcriptional and functional properties of microglia. These differences could be mediated by both sex hormone signaling and genes on the sex chromosomes.The prevalence, incidence, and disease progression of many neurological diseases vary by sex. Microglial sex differences could become maladaptive during disease states and underlie some of the sex differences in neurodegenerative diseases.
Single-cell RNA sequencing is an increasingly used method to measure gene expression at the single cell level and build cell-type atlases of tissues. Hundreds of single-cell sequencing datasets have ...already been published. However, studies are frequently deposited as raw data, a format difficult to access for biological researchers due to the need for data processing using complex computational pipelines. We have implemented an online database, PanglaoDB, accessible through a user-friendly interface that can be used to explore published mouse and human single cell RNA sequencing studies. PanglaoDB contains pre-processed and pre-computed analyses from more than 1054 single-cell experiments covering most major single cell platforms and protocols, based on more than 4 million cells from a wide range of tissues and organs. The online interface allows users to query and explore cell types, genetic pathways and regulatory networks. In addition, we have established a community-curated cell-type marker compendium, containing more than 6000 gene-cell-type associations, as a resource for automatic annotation of cell types.
The increasingly stringent requirement in large‐scale energy storage necessitates the development of high‐performance sodium‐ion batteries (SIBs) that can operate under low‐temperature (LT) ...environment. Although SIBs can achieve good cycling stability and rate performance at room temperature, the sluggish electrochemical reaction kinetics at low temperature remains a great challenge for SIBs. Here, a superior LT SIB composed of 3D porous Na3V2(PO4)3/C (NVP/C‐F) and NaTi2(PO4)3/C foams (NTP/C‐F) is developed. First‐principles calculations reveal that the intrinsic Na+ diffusivity in NASICON‐type NVP and NTP is extremely high (maximum 3.84 × 10−5 for NVP and 2.94 × 10−9 cm2 s−1 for NTP) at –20 °C. In addition, the designed 3D interconnected porous foam structures demonstrate excellent electrolyte absorption ability and Na+ transport performance at low temperature. As a result, under −20 °C, the NVP/CF and NTP/CF electrodes (half‐cell configuration) can attain reversible capacities close to their theoretical values, and are able to be charged and discharged rapidly (20 C) for 1000 cycles. Based on these features, the designed NTP/CF||NVP/CF full cell also displays superb LT kinetics and cycling stability, making a great stride forward in the development of LT SIBs.
A high‐performance low‐temperature sodium ion full battery composed of 3D porous Na3V2(PO4)3/C and NaTi2(PO4)3/C foams is developed. Owing to the fast Na+ diffusivity of these two NASICON‐type electrodes and excellent electrolyte absorption ability of the foam structure, this full battery demonstrates superb kinetics and cycling stability (e.g., 20 C over 1000 cycles) at −20 °C.
Solar-driven overall water splitting is highly desirable for hydrogen generation with sustainable energy sources, which need efficient, earth-abundant, robust, and bifunctional electrocatalysts for ...both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, we propose a heterogeneous bimetallic phosphide/sulfide nanocomposite electrocatalyst of NiFeSP on nickel foam (NiFeSP/NF), which shows superior electrocatalytic activity of low overpotentials of 91 mV at −10 mA cm–2 for HER and of 240 mV at 50 mA cm–2 for OER in 1 M KOH solution. In addition, the NiFeSP/NF presents excellent overall water splitting performance with a cell voltage as low as 1.58 V at a current density of 10 mA cm–2. Combining with a photovoltaic device of a Si solar cell or integrating into photoelectrochemical (PEC) systems, the bifunctional NiFeSP/NF electrocatalyst implements unassisted solar-driven water splitting with a solar-to-hydrogen conversion efficiency of ∼9.2% and significantly enhanced PEC performance, respectively.
Stimuli-responsive unimolecular chirality switching is a highly intriguing topic because the molecular structure as well as its function can be adjusted simultaneously by a switching process. Herein, ...a novel acid/base-tunable unimolecular chirality switching system based on a pillar5azacrown pseudo1catenane is reported. The bicyclic pillar5azacrown pseudo1catenane PN4 is synthesized through fusing an azacrown ring onto one repeating unit of a pillar5arene. Protonation and deprotonation can reversibly regulate the conformational transformations of PN4 between self-inclusion and self-exclusion structures, which results in the chiroptical inversions of the pseudo1catenane. NMR spectra, circular dichroism spectra, and single-crystal structures demonstrate these processes. This pseudo1catenane is a novel pillararene-based unimolecular chirality switching system driven by acid/base responsiveness and reveals a new perspective on the supramolecular chirality chemistry of macrocycles.
Piezo‐electrocatalysis as an emerging mechano‐to‐chemistry energy conversion technique opens multiple innovative opportunities and draws great interest over the past decade. However, the two ...potential mechanisms in piezo‐electrocatalysis, i.e., screening charge effect and energy band theory, generally coexist in the most piezoelectrics, making the essential mechanism remain controversial. Here, for the first time, the two mechanisms in piezo‐electrocatalytic CO2 reduction reaction (PECRR) is distinguished through a narrow‐bandgap piezo‐electrocatalyst strategy using MoS2 nanoflakes as demo. With conduction band of −0.12 eV, the MoS2 nanoflakes are unsatisfied for CO2‐to‐CO redox potential of −0.53 eV, yet they achieve an ultrahigh CO yield of ≈543.1 µmol g−1 h−1 in PECRR. Potential band position shifts under vibration are still unsatisfied with CO2‐to‐CO potential verified by theoretical investigation and piezo‐photocatalytic experiment, further indicating that the mechanism of piezo‐electrocatalysis is independent of band position. Besides, MoS2 nanoflakes exhibit unexpected intense “breathing” effect under vibration and enable the naked‐eye‐visible inhalation of CO2 gas, independently achieving the complete carbon cycle chain from CO2 capture to conversion. The CO2 inhalation and conversion processes in PECRR are revealed by a self‐designed in situ reaction cell. This work brings new insights into the essential mechanism and surface reaction evolution of piezo‐electrocatalysis.
Piezo‐electrocatalysis as an emerging mechano‐to‐chemistry energy conversion technique opens multiple innovative opportunities, drawing great interest but also suffering from the controversial mechanisms. A narrow‐bandgap piezo‐electrocatalyst strategy is proposed by choosing CO2 reduction as a probe reaction to distinguish the two potential mechanisms, i.e., screening charge effect and energy band theory, and reveal that piezo‐electrocatalysis is independent of band positions.
Utilizing photocatalysis to split water is a highly prospective technique for H2 evolution. However, carrier recombination in photocatalysts results in poor photocatalytic H2 evolution performance. ...The introduction of metallic substances as cocatalysts has found extensive application in enhancing photocatalytic performance. However, the existence of Schottky barriers remains a hindrance to the separation of photogenerated carriers. In this work, the electronic structure of g-C3N4 was modulated and optimized by P doping, changing the contact mode from the Schottky contact to the Ohmic contact, greatly promoting photogenerated charge separation and transfer. Under xenon lamp illumination, the H2 production rate of the prepared Ohmic contact photocatalyst is nearly 5 times that of the original Schottky contact one. This work gives new insights into the rational design of an efficient water-splitting photocatalyst.
The design and development of efficient photocatalyst is the key to raising the efficiency of H2 production via photocatalytic water-splitting. Herein, NiS2/H2O2–CdS (NC) composite photocatalysts ...were prepared by modifying CdS with H2O2 and using NiS2 as the cocatalyst. The experimental results showed that NC had excellent H2 evolution activity (42.21 mmol g−1 h−1), 136.2 times that of pure CdS, 3.8 times that of Pt/CdS (11.24 mmol g−1 h−1). Based on the detailed experimental characterization and DFT calculations, the excellent photocatalytic activity was discovered. Firstly, H2O2 changes the morphology of CdS from cone shape to mesoporous particles and greatly increases its specific surface area and also improves the diffusion of H2. Secondly, the cocatalyst NiS2 extends the range of light absorption, more importantly, it makes both the migration of electrons and reduction of H+/H3O+ much easier because it is metallic and of low absorption/desorption Gibbs energy for hydrogen.
•NiS2/H2O2–CdS catalyst has excellent hydrogen evolution performance and high stability.•H2O2 changes the morphology of CdS and greatly increases its specific surface area.•The hydrogen evolution mechanism of NiS2/H2O2–CdS is proposed.
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