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The use of gas diffusion electrode (GDE) based flow cell can realize industrial-scale CO2 reduction reactions (CO2RRs). Controlling local CO2 and CO intermediate diffusion plays a key role in CO2RR toward multi-carbon (C2+) products. In this work, local CO2 and CO intermediate diffusion through the catalyst layer (CL) was investigated for improving CO2RR toward C2+ products. The gas permeability tests and finite element simulation results indicated CL can balance the CO2 gas diffusion and residence time of the CO intermediate, leading to a sufficient CO concentration with a suitable CO2/H2O supply for high C2+ products. As a result, an excellent selectivity of C2+ products ~ 79% at a high current density of 400 mA·cm−2 could be obtained on the optimal 500 nm Cu CL (Cu500). This work provides a new insight into the optimization of CO2/H2O supply and local CO concentration by controlling CL for C2+ products in CO2RR flow cell. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction reaction (CO2RR) to multi‐carbon products (C2+) in acidic electrolyte is one of the most advanced routes for tackling our current climate and energy crisis. However, the competing hydrogen evolution reaction (HER) and the poor selectivity towards the valuable C2+ products are the major obstacles for the upscaling of these technologies. High local potassium ions (K+) concentration at the cathode's surface can inhibit proton‐diffusion and accelerate the desirable carbon‐carbon (C−C) coupling process. However, the solubility limit of potassium salts in bulk solution constrains the maximum achievable K+ concentration at the reaction sites and thus the overall acidic CO2RR performance of most electrocatalysts. In this work, we demonstrate that Cu nanoneedles induce ultrahigh local K+ concentrations (4.22 M) – thus breaking the K+ solubility limit (3.5 M) – which enables a highly efficient CO2RR in 3 M KCl at pH=1. As a result, a Faradaic efficiency of 90.69±2.15 % for C2+ (FEC2+) can be achieved at 1400 mA.cm−2, simultaneous with a single pass carbon efficiency (SPCE) of 25.49±0.82 % at a CO2 flow rate of 7 sccm. [ABSTRACT FROM AUTHOR]

With increasing CO2 emission and energy scarcity, electrocatalytic CO2 reduction reaction (CO2RR) offers an attractive solution for CO2 resource utilization using sustainable electrical energy. Ag‐based catalysts with high‐curvature nanoneedle structure exhibit the potential to achieve high CO2RR activity, but suffer from insufficient stability due to the vulnerability of the high‐curvature structure during CO2RR. Herein, the uniform porous Zn conformal coating on high‐curvature dendritic Ag nanoneedles (AgNNs@Zn) by vacuum thermal evaporation is prepared. As the surface sacrificial shell, the dissolution and reconstruction of Zn protect the inner Ag core, thus enhancing the CO2RR stability of AgNNs@Zn. The concentration of Ag+ in the electrolyte after 2 h CO2RR electrolysis markedly reduces from 2.4 ug L−1 in AgNNs to 1.4 ug L−1 in AgNNs@Zn. Moreover, the DFT calculation reveals that the constructed Ag–Zn interfaces can stabilize the *COOH intermediates, which promote the selectivity of CO2 reduction into CO. As a result, the optimized AgNNs@Zn catalyst exhibits the FECO of ≈91% at −0.86 V versus RHE in H‐cell, and FECO of 90% at 100 mA cm−2 above 12 h in flow cell. This work provides a feasible strategy to synthesize bimetallic catalysts with core–shell structure for better CO2RR performance. [ABSTRACT FROM AUTHOR]

Designing and synthesizing efficient molecular catalysts may unlock the great challenge of controlling the CO2 reduction reaction (CO2RR) with molecular precision. Nickel phthalocyanine (NiPc) appears as a promising candidate for this task due to its adjustable Ni active‐site. However, the pristine NiPc suffers from poor activity and stability for CO2RR owing to the poor CO2 adsorption and activation at the bare Ni site. Here, a ligand‐tuned strategy is developed to enhance the catalytic performance and unveil the ligand effect of NiPc on CO2RR. Theoretical calculations and experimental results indicate that NiPc with electron‐donating substituents (hydroxyl or amino) can induce electronic localization at the Ni site which greatly enhances the CO2 adsorption and activation. Employing the optimal catalyst—an amino‐substituted NiPc—to convert CO2 into CO in a flow cell can achieve an ultrahigh activity and selectivity of 99.8% at current densities up to −400 mA cm−2. This work offers a novel strategy to regulate the electronic structure of active sites by ligand design and discloses the ligand‐directed catalysis of the tailored NiPc for highly efficient CO2RR. [ABSTRACT FROM AUTHOR]

In recent years, many studies have focused on autophagy, an evolutionarily conserved mechanism that relies on lysosomes to achieve cellular metabolic requirements and organelle turnover, and revealed its important role in animal models of traumatic injury. Autophagy is a double‐edged sword. Appropriate levels of autophagy can promote the removal of abnormal proteins or damaged organelles, while hyperactivated autophagy can induce autophagic apoptosis. However, recent studies suggest that autophagic flux seems to be blocked after traumatic brain injury (TBI), which contributes to the apoptosis of brain cells. In this study, valproic acid (VPA), which was clinically used for epilepsy treatment, was used to treat TBI. The Morris water maze test, hematoxylin & eosin staining and Nissl staining were first conducted to confirm that VPA treatment had a therapeutic effect on mice after TBI. Western blotting, enzyme‐linked immunosorbent assay and immunofluorescence staining were then performed to reveal that VPA treatment reversed TBI‐induced blockade of autophagic flux, which was accompanied by a reduced inflammatory response. In addition, the variations in activation and phenotypic polarization of microglia were observed after VPA treatment. Nevertheless, the use of the autophagy inhibitor 3‐methyladenine partially abolished VPA‐induced neuroprotection and the regulation of microglial function after TBI, resulting in the deterioration of the central nervous system microenvironment and neurological function. Collectively, VPA treatment reversed the TBI‐induced blockade of autophagic flux in the mouse brain cortex, subsequently inhibiting brain cell apoptosis and affecting microglial function to achieve the promotion of functional recovery in mice after TBI. Cover Image for this issue: doi: 10.1111/jnc.14755. [ABSTRACT FROM AUTHOR]

Designing and synthesizing efficient molecular catalysts may unlock the great challenge of controlling the CO2 reduction reaction (CO2RR) with molecular precision. Nickel phthalocyanine (NiPc) appears as a promising candidate for this task due to its adjustable Ni active‐site. However, the pristine NiPc suffers from poor activity and stability for CO2RR owing to the poor CO2 adsorption and activation at the bare Ni site. Here, a ligand‐tuned strategy is developed to enhance the catalytic performance and unveil the ligand effect of NiPc on CO2RR. Theoretical calculations and experimental results indicate that NiPc with electron‐donating substituents (hydroxyl or amino) can induce electronic localization at the Ni site which greatly enhances the CO2 adsorption and activation. Employing the optimal catalyst—an amino‐substituted NiPc—to convert CO2 into CO in a flow cell can achieve an ultrahigh activity and selectivity of 99.8% at current densities up to −400 mA cm−2. This work offers a novel strategy to regulate the electronic structure of active sites by ligand design and discloses the ligand‐directed catalysis of the tailored NiPc for highly efficient CO2RR. [ABSTRACT FROM AUTHOR]