Hairong Xue

Li–CO ₂ batteries are promising due to their high theoretical energy density and CO ₂ utilization, but practical applications are limited by sluggish Li ⁺ transport, severe polarization, and unstable liquid electrolytes. Herein, we develop a novel composite solid electrolyte (CSE) by integrating polar‐segment engineering with metal–organic framework (MOF) modification. The oxygen‐containing groups of poly(allyl acetoacetate) (PAAA) provide abundant coordination sites for rapid Li ⁺ transport, while amino‐functionalized UiO‐66‐NH ₂ immobilizes TFSI ⁻ anions and promotes lithium‐salt dissociation. Density functional theory (DFT) calculations and molecular dynamics (MD) simulations reveal strengthened Li ⁺ coordination, weakened Li ⁺ –TFSI ⁻ association, and more continuous Li ⁺ diffusion pathways. Benefiting from the optimized ion‐conduction network and improved Li/electrolyte interface, the CSE exhibits a high ionic conductivity (6.64 × 10 ⁻⁴ S cm ⁻¹ at 30 °C), an enhanced Li ⁺ transference number (0.46), and oxidative stability up to 4.96 V vs. Li ⁺ /Li. Consequently, the assembled solid‐state Li–CO ₂ battery delivers a high discharge capacity of 28908 mAh g ⁻¹ at 200 mA g ⁻¹ and exceptional cycling stability over 3600 h. Separately, the PAU‐based Li–air battery under ambient‐air conditions exhibits stable cycling for 500 h. This work provides an effective strategy for interfacial and ion‐transport engineering toward high‐performance solid‐state Li–CO ₂ batteries.

Strain engineering has emerged as an effective strategy to regulate the electronic structure of nonprecious transition-metal-based electrocatalysts for enhanced oxygen evolution reaction (OER) activity. Nevertheless, in most reported electrocatalyst systems, the use of other catalytically active transition metal ion dopants couples strain effects with dopant-derived d electronic configuration modifications and even active sites, thereby obscuring the intrinsic role of lattice strain. Herein, strain-dominant engineering of hematite (α-Fe2O3) for efficient OER was achieved via electronically inert Mg2+ doping. Combined experimental and theoretical analyses revealed that Mg2+ substitution induces lattice expansion and intrinsic tensile strain in the α-Fe2O3 lattice, which modulates the local Fe–O coordination environment and enhances Fe–O orbital interaction, thereby leading to more favorable adsorption energetics of OER intermediates. As a result, Mg2+-doped α-Fe2O3 nanoparticles with optimized Mg2+ content of 1.53% exhibited a substantially reduced overpotential, delivering a current density of 10 mA cm–2 at 0.406 V compared to 0.453 V for pristine α-Fe2O3, along with a significantly decreased Tafel slope from 161.5 to 99.6 mV dec–1. This work establishes electronically inert dopant-induced strain engineering as an effective strategy for enhancing the electrocatalytic performance of iron-based oxide nanocatalysts by regulating Fe–O orbital coupling and oxygen intermediate adsorption.

The resource-abundant tin dioxide-based materials exhibit high theoretical capacity for lithium-ion batteries, yet their practical applications are obstructed by low initial Coulombic efficiency (ICE) and poor cycling lifespan. These issues...

An in situ grown nanomaterial with an array structure, abundant active catalytic sites and broad-spectrum absorption was used as photo-cathode for photo-assisted Li–O ₂ battery.

The design and development of efficient catalysts for electrochemical nitrogen reduction reaction (ENRR) under ambient conditions are critical for the alternative ammonia (NH₃) synthesis from N₂ and H₂O, wherein iron‐based electrocatalysts exhibit outstanding NH₃ formation rate and Faradaic efficiency (FE). Here, the synthesis of porous and positively charged iron oxyhydroxide nanosheets by using layered ferrous hydroxide as a starting precursor, which undergoes topochemical oxidation, partial dehydrogenated reaction, and final delamination, is reported. As the electrocatalyst of ENRR, the obtained nanosheets with a monolayer thickness and 10‐nm mesopores display exceptional NH₃ yield rate (28.5 µg h⁻¹ mg_cat.⁻¹) and FE (13.2%) at a potential of −0.4 V versus RHE in a phosphate buffered saline (PBS) electrolyte. The values are much higher than those of the undelaminated bulk iron oxyhydroxide. The larger specific surface area and positive charge of the nanosheets are beneficial for providing more exposed reactive sites as well as retarding hydrogen evolution reaction. This study highlights the rational control on the electronic structure and morphology of porous iron oxyhydroxide nanosheets, expanding the scope of developing non‐precious iron‐based highly efficient ENRR electrocatalysts.

Solid-state Li_1+xAl_xGe_2−x(PO₄)₃ electrolytes with high ionic conductivity were prepared and successfully applied in lithium–oxygen batteries (LOBs). Combined with MOF-derived NiCo₂O₄ cathodes, the solid-state LOBs deliver a high discharge capacity and good rate performance. Moreover, enabled by such a bifunctional cathode, the as-assembled solid-state LOBs show enhanced reversibility and long-term cycling stability over 90 cycles.

Electrochemical reduction of N₂ represents a very attractive approach for sustainable NH₃ production at environmental temperature and pressure. The design of highly branched Pd-based nanoarchitectonics is very important for the electrocatalytic N₂ reduction reaction (NRR). Herein, we propose a very simple synthetic method for direct fabrication of unique bi-metallic PdRu nanorod assemblies (PdRu NRAs) with high yield in an aqueous solution. Owing to their branched shape together with bi-metallic compositions, the self-supported PdRu NRAs assembled with staggered nanorods show high catalytic activity and superior durability for the NRR. The presented direct synthetic strategy is very valuable for the design of active branched metallic catalysts for the NRR.

High surface area and fast mass transport rate are important to enhance the activity and stability of catalysts. In this work, tellurium nanowires and F127 triblock copolymer are used as self‐sacrificial and soft templates, respectively, to synthesize PtRuTe mesoporous nanotubes (MNTs). The designed PtRuTe MNTs show uniformly distributed mesopores and an internally hollow structure, which can effectively improve Pt utilization, the catalytic activity and durability, and CO tolerance for the methanol oxidation reaction. Very different from previous 1D metallic catalysts with solid interiors and smooth surfaces, PtRuTe MNTs are unique, with a mesoporous exterior and hollow interior. The facile route presented herein is very feasible for fabricating 1D mesoporous metallic catalysts.

Quaternary PtPdNiP mesoporous nanospheres (PtPdNiP MNs) with uniform morphology and size are synthesized for enhanced oxygen reduction electrocatalysis.