Huan Pang

Ligand design regulates structure/porosity, conjugation/transport, redox activity, interfacial chemistry, and metal-node/disorder coupling, establishing a molecular basis for rational MOF energy-storage design.

Electrocatalytic nitrate reduction (NO3RR) offers a “two birds with one stone” strategy by simultaneously removing pollutants and producing value-added ammonia (NH3). However, its multiple electron- and proton-transfer steps require catalysts with both high activity and selectivity. Copper (Cu) is widely regarded as one of the most promising NO3RR electrocatalysts due to its low cost and relatively high activity, yet its ammonia yield rate is usually constrained by sluggish nitrite conversion kinetics. Herein, a series of Cu-based catalysts with distinct oxidation states and crystallinity were derived from Cu-based metal−organic framework nanosheets (Cu-MOF NSs) by adjusting the pyrolysis conditions, and their NO3RR performance in alkaline media was evaluated. The low-crystallinity copper oxide catalyst (CuO-1) achieved the highest NH3 yield rate of 11.5 mg cm−2 h−1 at −0.8 V vs reversible hydrogen electrode (RHE), significantly outperforming the metallic Cu catalyst (Cu@NC), the highly crystalline CuO catalyst (CuO-2), and most previously reported catalysts. Mechanistic investigations suggest that CuO-1 undergoes partial reduction during the reaction to generate Cu0/Cu+ species, which may serve as key active species promoting ammonia production by enhancing active hydrogen generation. Finally, NH4Cl was recovered through acid absorption and rotary evaporation, demonstrating a practical route for converting NO3− pollutants into valuable NH3 products.

Rechargeable Na‐Cl ₂ batteries have emerged as a promising alternative and supplement for lithium‐ion batteries due to their ultra‐high energy density. Nevertheless, developing satisfactory cathode materials to facilitate the complex solid, liquid, and gas three‐phase conversion process during charge‐discharge cycling remains a significant challenge. Herein, we propose a three‐dimensional ordered macroporous Prussian blue analog (3DOM PBA) fabricated via a stepwise vacuum impregnation template strategy, which can serve as an ideal cathode material for rechargeable Na‐Cl ₂ batteries. The hierarchically ordered porous structure arranging from micropores to macropores can provide appropriated channels for ions transfer, Cl ₂ storage, and NaCl crystal deposition. Moreover, customizable metal site doping not only optimize the electronic and ionic conductivity but also provide efficient adsorption and in‐situ catalytic conversion sites for Cl ₂ /Cl ⁻ , thereby effectively increasing the reversible reaction kinetics and long‐term cycling stability. As a result, the assembled Na‐Cl ₂ battery delivers a reversible capacity of 2000 mAh g ^{− 1} and stable cycling life of 2500 cycles at 15 000 mA g ^{− 1} , which can still maintain reversible charge‐discharge behavior even at 30 000 mA g ^{− 1} , much superior to the reported results. This study provides new insights for developing high‐performance electrode materials for rechargeable Na‐Cl ₂ batteries.

Infected wounds are characterized by a depth‑dependent hypoxic gradient: bacterial biofilms consume oxygen at the surface, while deeper tissue suffers from severe hypoxia that impairs healing. To address this, we designed a piezoelectric microneedle (MN) patch to leverage this oxygen gradient to achieve zone‑specific therapy by embedding cobalt‑doped bismuth ferrite nanoparticles (CBFO NPs) into a silk fibroin methacrylate (SFMA) hydrogel. Co3+ substitution for Fe3+ creates a morphotropic phase boundary, narrows the band gap, and increases free electron density, collectively enhancing piezoelectric performance and charge separation under ultrasound (US) irradiation. Subjected to ultrasound sonication, the microneedle substrate generates abundant reactive oxygen species (ROS) in the normoxic surface layer, effectively eradicating bacteria and disrupting biofilms, while the CBFO NPs in the microneedle tips decompose endogenous H2O2 to produce oxygen and alleviate deep-seated hypoxia without the need for external oxygen. Furthermore, the US‑induced piezoelectric effect provides localized electrical stimulation that promotes fibroblast migration and proliferation. In an infected full‑thickness mouse model, the US‑activated SFMA/CBFO MN patch accelerated wound closure, reduced bacterial load, and enhanced collagen deposition and angiogenesis. This spatially heterogeneous antibacterial‑oxygenation strategy exploits the natural oxygen gradient, offering a promising platform for difficult‑to‑heal wounds.

This review summarizes the synthesis and application of microspherical graphene-based heterostructures. The fundamental catalytic and charge storage mechanisms are studied, and the effects of heterostructure on relative performance are addressed.

Pore engineering plays a decisive role in governing the water desalination and contaminant treatment performance of metal–organic framework (MOF)-derived carbons. Herein, hierarchical porous carbons with tunable architectures are prepared through the pyrolysis of ZIF-9 followed by controllable hydrochloric acid etching. The acid treatment reopens blocked pore channels, effectively increases the surface area, and generates abundant accessible active sites, thereby accelerating ionic diffusion and enhancing interfacial adsorption. As a result, the etched carbons exhibit markedly enhanced capacitive deionization (CDI) performance relative to their pristine counterparts, delivering higher salt adsorption capacity, faster ionic migration rate, and superior cyclic stability. Experimental results confirm that 24 h of HCl etching is optimal, which enhances interfacial adsorption while preserving the structural integrity of the carbon skeleton. More importantly, the optimized electrode achieves simultaneous removal of inorganic salts, tetracycline, and heavy metal ions, overcoming the single-function limitation of conventional CDI systems. Theoretical calculations confirm that the synergy between pore-assisted physical diffusion and active-site-dominated chemical adsorption endows the material with excellent multifunctional purification performance. This work elucidates the structure–activity relationship of etching conditions, pore evolution, and water-treatment performance and provides a facile and scalable strategy for the rational design of multifunctional carbon electrodes for complex wastewater remediation.

Electrochemical reduction of ammonia represents a highly promising approach for transforming harmful environmental pollutants into more valuable products. In this study, we successfully achieved precise control over the environment surrounding single‐atom Ni sites by modifying functional groups on ligands. To validate this strategy, we constructed two similar hollow Ni‐MOFs. The metal–organic frameworks (MOFs) containing the p‐type tetraazanaphthotetraphene ligand (Ni‐TT) demonstrated exceptional performance compared to n‐type triphenylene (Ni‐TP). Its overall reduction rate reached 196.9 µmol·h ⁻¹ ·cm ² , with a Faraday efficiency as high as 90.9% at −0.4 V versus RHE. The exceptional performance of Ni‐TT stems from the p‐type tetranaphthalenetetracene ligand, which is nitrogen‐rich and electron‐deficient. The electronic properties of the ligand significantly influence the coordination environment around the single‐atom Ni site, enabling precise control over proton‐transfer behavior during the reaction. Theoretical calculations also indicate that hydrogen adsorption on p‐type Ni‐TT surfaces accelerates hydrogen transfer at Ni active sites compared to n‐type Ni‐TP. This significantly enhances the rate‐determining step (RDS) in the NO hydrogenation process. The constructed Ni‐TT‐based Zn‐NO battery achieved a power density of 2.1 mW cm ⁻² . These results provide insight into how conjugated ligand structures modulate the electronic structure and hydrogenation behavior, which may guide future studies on MOF‐based electrocatalysts for nitric oxide reduction reaction (NORR).