Converting captured carbon dioxide (CO₂) into valuable chemicals and fuels through electrocatalysis and realizing the anthropogenic closed-carbon cycle can provide new solutions to environmental and energy problems. Nanoporous organic frameworks, including metal-organic frameworks (MOFs) and porous organic polymers (POPs), as a class of potential electrocatalysts, have made great progress in CO₂ reduction reaction due to their high porosity, large specific surface area, and structural/functionalization diversity. In this review, the recent developments in pristine MOFs/POPs, MOFs/POPs composite, and MOFs-/POPs-derived catalysts are discussed from aspects of catalyst design, synthesis strategy, test techniques, performance validation, active sites, and basic mechanism. We further summarize the challenges and prospects of MOFs/POPs-based materials in practical applications for CO₂ reduction reactions and point out the potential paths of future research. This review can provide a comprehensive reference for the advanced design and systematic cognition of efficient nanoporous organic framework catalysts for electrocatalytic CO₂ reduction.

Graphite has long served as one of the most commonly used anode materials in lithium-ion batteries, where its electrochemical-mechanical coupling performance is critical for maintaining structural stability and extending cycle life. This study investigates the evolution of the electrochemical-mechanical coupling characteristics of graphite electrodes during electrochemical cycling. Experiments were performed using in situ curvature testing, combined with in situ X-ray Diffraction analysis. A physical model was created to analyze the variations in curvature, Young's modulus, strain, and partial molar volume of the graphite composite electrodes. The results indicate that the modulus of elasticity augments with the concentration of lithium ions during lithiation. Additionally, the partial molar volume undergoes periodic changes with the state of charge. In-situ X-ray Diffraction experiments revealed the lithiation phase transformation process in graphite. The interlayer spacing was calculated by tracking the evolution of the (001) and (002) diffraction peaks, which verified the accuracy of the partial molar volume during the electrochemical cycle. This further elucidates the phase transformation mechanisms of lithium intercalation and the volumetric changes of the active material within the graphite anode.

Improving the volumetric energy density of carbon electrode materials for supercapacitors is of significance to reducing the size of energy storage devices, and eliminating the ineffective pores in porous carbon electrode materials is the key to achieving dense storage of ions. Herein, we reconstruct the pore structure of commonly activated carbon via a facile high-energy mechanochemical process, by which modified activated carbon exhibits a much-increased packing density with an ultra-low specific surface area of 33 m² g^-1 without sacrificing the gravimetric specific capacitances, thereby enabling high volumetric capacitances up to 602 F cm^-3. Gas adsorption characterization and small angle X-ray scattering tests collectively reveal the regulatory mechanism of mechanochemical process on pore structure reconstruction that high-energy mechanochemical treatment significantly eliminates the excess meso-/macro-pore volume to configure a compressed carbon skeleton structure and simultaneously increases proportions of micropore volume in the total pore volume, ultimately resulting in a cross-linked dense pore network structure. Benefitting from the optimized pore network and oxygen atoms introduced by mechanochemistry, the assembled aqueous symmetric supercapacitor in KOH electrolyte delivers a maximum volumetric energy density of 11.32 Wh L^-1 when the volumetric power density is 223 W L^-1. This work systematically reveals the effects of mechanical force on the pore reconstruction of carbon materials, and provides a simple method for enhancing the volumetric performances of carbon-based porous electrode materials.

Direct ethanol fuel cells are considered indispensable and prospective energy storage devices due to their high volumetric energy density. Platinum (Pt) and Pt-based alloys are regarded as the most effective catalysts for both oxygen reduction reaction (ORR) and ethanol oxidation reaction. To further enhance the catalytic performance of the catalyst, it is necessary to improve the mass activity and utilization efficiency of Pt. In this work, we report a strategy for fabricating ordered mesostructured platinum-palladium alloy nanotubes (MPPNs) with high hierarchical porosity (68%) and abundant exposed active edge sites. MPPNs exhibit excellent catalytic activity and stability for ORR, with a mass activity approximately 7.4 times higher than that of the commercial Pt/C catalyst. After 20 k cycles of accelerated durability test for ORR, MPPNs demonstrate impressive retention of their original mass activity, maintaining a value of 93.9%. Furthermore, they display superior catalytic activity and stability for ethanol oxidation reactions, with a mass activity about 2.4 times higher than that of commercial Pt/C. After the 2,000 scan cycles, the mass activity remains at 84.5% of initial performance. Both experimental and theoretical studies reveal that the synergistic effect of neighboring (111) and (100) facets on the edge sites plays a critical role in enhancing the electrocatalytic selectivity, activity and stability.

The energy harvesting crisis has caused great necessity for new energy technologies, among which triboelectric nanogenerators (TENGs) garnered global attention. Based on our previous research on a novel 2D material graphitic carbon nitride (g-C₃N₄), this work explores the influence of g-C₃N₄ hybrid dopants with Polydimethylsiloxane (PDMS) on the performance enhancement of TENGs. More specifically, systematic experiments with different ratios of hybrid dopants were conducted, including Ag nanowires with g-C₃N₄, carbon nanotubes with g-C₃N₄, and MXene with g-C₃N₄. The systematic and optimization studies showed that carbon nanotube/g-C₃N₄ at the optimal ratio of 1:1 in PDMS composite presented an open circuit voltage (Voc) at 122 V, a short circuit current (Isc) at 5.8 μA, and a charge transfer (Qsc) at 105 nC_, while Ag/g-C₃N₄ at the ratio of 3:1 with 1 wt % in PDMS composite presented the best performance with Voc of 92 V, Isc of 4.6 μA, Qsc of 49 nC, and power density of 1.45 W/m². The fabricated hybrid dopant/PDMS TENG was utilized for versatile applications in biomechanical energy harvesting and self‐powered human-motion detecting. In addition, we designed a dish and an insole with multiple TENGs for pressure sensing and multichannel data acquisition applications.

The production of storable hydrogen fuel through water splitting, powered by renewable energy sources such as solar photovoltaics, wind turbines, and hydropower systems, represents a promising path toward achieving sustainable energy solutions. Transition-metal phosphides (TMPs) have excellent physicochemical properties, making them the most promising electrocatalysts for hydrogen evolution reaction (HER). Traditionally, achieving good crystallinity in these TMPs typically requires prolonged (≥ 2 h) high-temperature pyrolysis, which is time-consuming and generally yields samples with large particle sizes, adversely affecting the catalytic activities. Herein, for the first time, we present a groundbreaking discovery in the synthesis of grain-boundary-rich RuP₂ nanoparticles within a very short time frame of nine seconds, using a fast Joule heating strategy (RuP₂ JH). Subsequent electrochemical tests reveal that the as-synthesized RuP₂ JH not only exhibits platinum-like HER activity, achieving overpotentials of 22 mV, 22 mV and 270 mV to reach a current density of 10 mA cm^-2 in 0.5 M H₂SO₄, 1.0 M KOH, and 0.1 M phosphate buffered solutions, respectively, but also exhibits exceptional long-term stability. Moreover, it exhibits a Faradaic efficiency exceeding 96%. This work significantly contributes to the expanding repertoire of TMPs synthesized via Joule heating by showcasing exceptional performance toward HER and other energy-related catalytic applications.

Iontronic power sources have attracted widespread attention in the field of energy harvesting and storage. However, conventional devices only generate an output voltage of ~1.0 V. Herein, we have developed units with an ultra-high voltage of ~2.0 V per unit based on osmotic effects and fine-tuning interfacial redox reactions. These systems are designed to harness the efficient ion dynamics of K⁺ within graphene oxide nanofluidic channels and tailor Faradaic processes at the interfaces. Printable, scalable, and optimized through fractal design, these miniaturized units are capable of directly powering commercial electronics, presenting a transformative paradigm for salinity gradient-based power generation. This approach offers a safe, ultra-thin, and portable solution for next-generation energy systems.

Atomically dispersed metal catalysts coordinated with nitrogen coordination and anchored to carbon substrates (M-N-C) have become highly effective alternatives to platinum-group catalysts for oxygen electrocatalysis. However, the catalytic efficacy of M-N-C systems remains constrained by the suboptimal performance associated with the symmetric charge distribution around the active metal centers. The synergistic co-design of asymmetric metal single-atom catalytic centers with heteroatom doping significantly enhances the bifunctional oxygen electrocatalytic activity and durability, advancing the capabilities of next-generation flexible zinc-air batteries. Herein, we developed a pyrolysis-secondary coordination strategy to generate a bifunctional oxygen electrocatalyst, characterized by single Co atoms integrated within an asymmetrical Co-N₅S₁ moiety, along with nanocluster complexes embedded in N,P,S-codoped carbon frameworks, labeled Co_SA+NC/NPSC. In the Co_SA+NC/NPSC catalyst, the Co-N₅S₁ active sites exhibit an optimized electronic configuration, achieved through the synergistic coordination of heteroatom doping and nanocluster integration. Theoretically, this configuration significantly lowers the energy barriers and adjusts the d-band center, ensuring a more balanced binding strength between active sites and the oxygen-containing intermediates and contributing to the promoted bifunctional oxygen reduction reaction/oxygen evolution reaction efficiency. The experimentally analytical results reveal that the Co_SA+NC/NPSC demonstrates an impressive oxygen evolution reaction activity (E_j=10 = 1.58 V) and a narrow bifunctional potential gap (ΔE = 0.75 V), remarkably superior to the counterparts with symmetric Co-S coordination or phosphorus-free doping. When assembled as an air electrode, the Co_SA+NC/NPSC-based flexible zinc-air battery exhibits ultralong charge-discharge life (> 105 h) and impressive initial round-trip efficiency of 72.42% even at 0 °C.

Sulfide-based solid electrolytes have emerged as pivotal components for the advancement of next-generation all-solid-state batteries, owing to the battery safety and higher energy density. This paper reviews the recent material innovations in sulfide-based solid electrolytes, focusing on enhancing their ionic conductivities based on an understanding of their crystal structures. Through a comprehensive analysis of current research trends and future perspectives, this review aims to provide a roadmap for the development of more robust and efficient sulfide-based solid electrolytes, which contribute to the realization of safer and higher-performance all-solid-state batteries.

Photothermal catalysis has emerged as a promising strategy for converting carbon dioxide (CO₂) into value-added chemicals and fuels, offering a dual-energy approach that combines light and thermal energy to drive reactions under mild conditions. Photothermal effects are usually demonstrated by using plasmonic nanoparticles, which generate hot carriers and localized heating through light absorption. These effects facilitate chemical reactions by lowering activation barriers and increasing reaction rates. The synergy between hot carrier-induced redox reactions and thermocatalytic processes driven by localized heating allows for the activation of challenging reactions with reduced energy inputs. The balance between these pathways can be optimized through rational design of photothermal catalysts. In this review, we highlight recent advancements in catalyst materials, especially emphasizing the importance of photothermal effects to achieve higher efficiencies in CO₂ conversion reactions such as CO₂ hydrogenation and dry reforming of methane, both of which are vital for reducing greenhouse gases and producing clean fuels. Finally, the current challenges, outlook, and new strategies for catalyst optimization will be discussed to realize the full potential of photothermal catalysis in creating a sustainable and low-carbon energy future.