ChemSusChem最新文献

The growing energy shortages and environmental damage make it urgent to activate chemical reactions under mild conditions, reducing energy consumption and improving efficiency. Mechanocatalysis, with its advantages of simplicity, scalability, and sustainability, has demonstrated exceptional performance in many key heterogeneous catalytic reactions and surpassed traditional catalytic methods. It possesses significant potential for future applications and development. In this review, recent advances in the field of mechanocatalysis for energy and environmental applications are systematically summarized. Meanwhile, insights into the design of effective mechanical catalysts and the mechanocatalytic reactions, especially those with gaseous reactants, are highlighted and discussed in detail. Lastly, challenges and future perspectives in the mechanocatalysis are described to guide its broader application in the field of catalysis.

The growing transition from fossil fuels to renewable energy sources such as wind and solar requires efficient stationary energy storage systems to ensure grid stability. Among emerging technologies, redox flow batteries (RFBs) offer a promising solution due to their unique decoupling of energy and power capacities, allowing flexible system design. Recent advances in organic RFBs (ORFBs) have highlighted redox-active organic molecules as sustainable alternatives to conventional vanadium-based systems, addressing issues of cost and corrosivity. In particular, nitroxide radicals such as tetramethylpiperidinyloxyl (TEMPO) derivatives have demonstrated high reversibility and fast kinetics in aqueous systems, though the stability of their oxidized N-oxoammonium form remains a challenge for long-term storage. Isoindoline-based nitroxides offer potential for enhanced stability but have been limited by complex and low-yield synthetic routes. Herein, we present a convenient metal-catalyzed [2 + 2 + 2] intermolecular cycloaddition strategy for the synthesis of isoindoline-based nitroxides and their aza analogs, including two new candidates, TC-TMIO and PPO. Electrochemical characterization reveals that PPO, a cationic 2,3-dihydropyrrolo[3,4-c]pyridinium nitroxide, exhibits an oxidation potential 220 mV higher than the benchmark 4-TMA-TEMPO and achieves solubility exceeding 3 M in 1 M NaCl aqueous solution. Preliminary stability assessments of the PPO and RFB testing using a methyl viologen/PPO system demonstrate its potential as a high-performance, sustainable posolyte for aqueous ORFBs.

Thermosetting polymers feature highly cross-linked networks that are fundamentally distinct from those of thermoplastics. Even with similar cross-linking point, their three-dimensional architecture imposes significant mass transfer barriers and necessitates harsh, energy-intensive degradation conditions. Overcoming these limitations to achieve efficient and low-energy recycling of epoxy thermosets remains a major challenge. To address this challenge, this article developed a cosolvent-enhanced diethylenetriamine (DETA) catalytic system that enables rapid and efficient degradation under mild conditions. This approach achieved complete decomposition within 30 min at 60°C, significantly reducing time and energy consumption compared to conventional methods. The cosolvents accelerate degradation by disrupting the resin morphology to enhance mass transport and activating the amine catalyst through hydrogen-bonding interactions. This article provides a practical and sustainable pathway for recycling of thermosetting polymers, highlighting the potential of solvent-catalyst synergy in promoting circular polymer economies.

Membrane electrode assembly (MEA) systems hold promise as a technology capable of achieving high stability and current density for electrochemical CO₂ reduction (ECR). The fabrication techniques, including the selection of MEA components, the defined technological route, and the activation process, determine both the normal operation of the system and the proper performance of catalysis. Besides, the mass transfer of ions and water within the membrane directly impacts the local microenvironment, ultimately leading to variations in product distribution. In this article, we elucidate the characteristics and functionalities of each component within the MEA electrolyzers. Additionally, the fabrication techniques and activation processes of MEA are emphasized for their practical production. Besides, the developments and challenges of MEA for ECR are concluded, along with proposed solutions. Finally, we concentrate on the ions transport and water management within MEA, which directly impacts the availability of MEA electrolyzers and the distribution of products for ECR.

Polyethylene terephthalate (PET), despite its extensive use, presents serious environmental concerns due to inefficient recycling and inevitable downcycling. In this work, a sustainable one-reactor upcycling strategy is developed to directly convert waste PET into functional metal–organic frameworks (MOFs). Using a biocompatible betaine catalyst and adopting a single-reactionvessel strategy, this integrated process substantially improves reaction efficiency and scalability. The strategy is further extended to other polyester plastics, such as polylactic acid (PLA), enabling the synthesis of six MOFs (Zn-BDC, Ca-BDC, Ni-BDC, Co-BDC, Zn-LA, and Ca-LA) with excellent crystallinity and tunable morphologies. When incorporated into polyvinylidene fluoride (PVDF) composite films, the PET-derived Zn-BDC exhibits superior passive radiative-cooling performance compared with conventional MOF-5 composites, achieving high solar reflectance (≈94.4%) and mid-infrared emissivity (≈95.5%), which lead to an average temperature reduction of 9.3°C below ambient conditions. Overall, this streamlined and scalable upcycling route provides an economically viable bridge between sustainable plastic-waste valorization and next-generation energy-saving materials.

Solid electrolytes (SEs) have attracted considerable attention in applications such as energy storage systems and electrical devices due to their intrinsic safety and high energy density. Among them, layered oxide-based SEs exhibit high stability, reasonable ionic conductivity, and lower sintering temperatures compared with other oxide-based SEs. Nevertheless, the demand for higher ionic conductivity and lower synthesis temperatures still persists. To address these challenges, this work explores a substitution strategy for Na₂Zn₂TeO₆ (NZTO), which shows the highest ionic conductivity among layered oxide SEs. Iron (Fe³⁺), one of the most earth-abundant elements, is employed to partially substitute Zn²⁺ in NZTO to enhance both stability and performance. This approach successfully improves ionic conductivity and lowers sintering temperature. Specifically, the ionic conductivity increases significantly from 0.469 mS/cm in pristine NZTO to 0.850 mS/cm at 25°C with 0.1 Fe substitution, and a pure P2 NZTO phase is obtained at 750°C, compared with 900°C for pristine NZTO. Furthermore, a 12.9% capacity enhancement and improved stability are achieved when fabricating a solid-state cell with 0.1 Fe³⁺-substituted NZTO compared with pristine NZTO, confirming its potential for applicability in all-solid-state batteries.

Electrochemical water splitting driven by renewable energy provides a sustainable route for generating high-purity hydrogen, yet its efficiency is hampered by the sluggish and economically unfavorable oxygen evolution reaction (OER) at the anode. Replacing OER with the urea oxidation reaction (UOR) has emerged as an attractive strategy to reduce energy input and simultaneously achieve wastewater remediation. Nevertheless, the six-electron transfer process of UOR still suffers from kinetic limitations, highlighting the urgent need for robust and cost-effective electrocatalysts. Recent progress has demonstrated that nanostructure-engineered catalysts enable precise regulation of surface electronic structures, optimization of intermediate adsorption energies, and enhancement of catalytic activity. In this review, we systematically summarize the recent advancements of nanostructural catalysts for UOR-assisted hydrogen evolution, highlighting how rational nanostructuring and compositional engineering contribute to improved intrinsic performance and energy efficiency. The underlying reaction mechanisms are critically discussed based on both experimental and theoretical perspectives. In addition, the practical application of the Zn-urea battery system is introduced, encompassing its electrochemical performance and potential for integrated energy storage and hydrogen production. Finally, we present the current challenges and propose future research directions aimed at bridging the gap between laboratory-scale studies and practical implementation.

Supercapacitors have garnered considerable attention as next-generation energy storage systems due to their high-power density, rapid charge–discharge kinetics, and long operational lifespan. In this study, we report the design and development of a nitrogen-doped activated borane (ActB), a porous borane cluster-based network, synthesized through the controlled cothermolysis of arachno-B₉H₁₃(NEt₃) and [Et₃NH][nido-B₁₁H₁₄] in toluene. The resulting polymeric materials integrate electron-rich nitrogen sites with the unique 3D boron cluster architecture, offering a synergistic platform for enhanced electrochemical performance. Electrochemical evaluation in a three-electrode system revealed a high specific capacitance of 607 F g⁻¹ at 0.5 A g⁻¹, with remarkable cycling stability, retaining 95% of the initial capacitance after 15,000 charge–discharge cycles. When configured into an asymmetric supercapacitor device using activated carbon as the negative electrode, the system achieved a specific capacitance of 354 F g⁻¹, along with an energy density of 25.6 Wh kg⁻¹ and a power density of 486.2 W kg⁻¹ at a current density of 0.5 A g⁻¹. The device also demonstrated long-term reliability, retaining 88% of its initial capacitance after 15,000 cycles. The outstanding performance is attributed to the integration of redox-active nitrogen functionalities and the inherent stability and tunability of the borane-based framework. This work establishes nitrogen-doped borane cluster polymers as a promising new class of electrode materials for high-performance supercapacitors and broader electrochemical energy storage applications.

Rechargeable zinc–air battery (ZAB) commercialization is hampered by low efficiency at the air cathodes, where sluggish kinetics and different reaction mechanisms for the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) at charging and discharging state, limit overall performance. Herein, we demonstrate a carbon nanotubes-supported ruthenium–manganese dioxide (Ru–MnO₂/CNTs) as a high-performance bifunctional ZABs catalyst fabricated via in situ growth and cation exchange approach. The catalyst features a hierarchical architecture where the CNTs scaffold serves as the structural backbone, while Ru–MnO₂ solid solution nanosheets with intrinsic bifunctional activity grow conformally on its surface. This CNTs-supported design synergistically enables a low ruthenium loading of 9.1 wt% while promising electrochemical performance. Critically, the catalyst achieves an ORR half-wave potential of 0.84 V, a OER overpotential of 210 mV at 10 mA cm⁻², and a narrow OER/ORR potential gap of merely 0.6 V. When integrated into ZABs, this catalyst exhibits excellent performance, with the peak power density of 156 mW cm⁻², a high specific capacity of 802 mA h g⁻¹, and stable cycling performance exceeding 200 h. Consequently, this work demonstrates a viable strategy for synthesizing cost-effective and highly active bifunctional oxygen electrocatalysts with optimized noble metal utilization.

With the surging global demand for renewable energy, stimuli-responsive hydrogels have emerged asa research hotspot in this field, owing to their unique stimuli-responsive properties, high water content, and remarkable design flexibility. First, this work systematically introduces the molecular and structural design strategies of stimuli-responsive hydrogels, encompassing diverse stimulus-responsive mechanisms. Subsequently, it comprehensively reviews the application progress of stimuli-responsive hydrogels in emerging energy technologies, including sustainable solar utilization, energy storage and conversion, and intelligent energy management. Additionally, the review analyzes current challenges and explores the future development directions of stimuli-responsive hydrogels in conjunction with sustainable development needs. This review not only comprehensively presents the application potential of stimuli-responsive hydrogels in the new energy field but also provides key references for the subsequent development of high-performance hydrogels and the advancement of renewable energy technologies.