Single-atom catalysts (SACs) have emerged as a focal point in energy catalytic conversion due to their remarkable atomic efficiency and catalytic performance. The challenge lies in efficiently anchoring active sites on a specific substrate to prevent agglomeration, maximizing their effectiveness. Substrate characteristics play a pivotal role in shaping the catalytic performance of SACs, influencing the dispersion and stability of single atoms. In recent years, amorphous materials have gained attention as substrates due to their unique surface structure and abundance of unsaturated coordination sites, offering an ideal platform for capturing and anchoring single atoms effectively, thus enhancing catalytic activity. To clarify the interaction between single atoms and amorphous substrates, this review outlines amorphization methods, the mechanism of single-atom anchoring and the characterization methods of amorphous SACs. Subsequently, it summarizes the physical properties and electrocatalytic mechanisms of amorphous materials. Then, interactions between single atoms and amorphous substrates are categorized and summarized. Finally, the paper consolidates the research progress of amorphous SACs and outlines future development prospects. By exploring the synergistic relationship between single atoms and amorphous substrates, this review aims to deepen the understanding of their interaction mechanisms, thereby propelling advancements in SACs for energy catalytic conversion.

The electrochemical reduction of carbon dioxide (CO₂RR) offers a promising approach to address the dual challenges of energy scarcity and environmental degradation. This study presents a new, cost-effective, and scalable electrocatalyst: self-supporting carbon paper modified with porous conjugated polyimides. This innovative material facilitates efficient CO₂ conversion in aqueous media, eliminating the need for a pyrolysis step. The electrocatalyst’s design utilizes a non-metallic organic polymer with a high density of nitrogen atoms, serving as active sites for catalysis. Its unique mesoporous microsphere structure comprises randomly stacked nanosheets that are generated in situ and aligned along the carbon fibers of carbon paper substrate. This architecture enhances both CO₂ adsorption and ensures proper electron transportation, facilitated by the conjugated structure of the polymer. Additionally, the inherent hydrophobicity of conjugated polyimides contributes to its robust catalytic performance in selectively reducing CO₂, yielding CO as the primary gaseous product with up to 88.7% Faradaic efficiency and 82.0 mmol g^-1 h^-1 yield rate. Therefore, the proposed electrocatalyst provides a sustainable solution for electrochemical CO₂RR catalyzed by non-metal organic materials, combining high efficiency with the advantages of a simple preparation process and the absence of costly materials or steps. This research contributes to the advancement of CO₂RR technologies, potentially leading to more environmentally friendly and energy-efficient solutions.

Lithium-ion capacitors (LICs) represent an innovative hybridization in the energy storage field, effectively combining the best features of supercapacitors and lithium-ion batteries. However, the theoretical advantage of LICs is impeded by the low reaction efficiency of the negative electrode material and significant volume expansion. Two-dimensional (2D) materials, due to their unique morphology, abundant pores, rich active centers, and adjustable composition, have been widely studied and developed as negative electrodes for LICs. Therefore, it is imperative to provide a timely review of the latest advancements in the field. The review initiates with a detailed exploration of the infrastructure, key performance evaluation parameters, and the underlying energy storage mechanisms that define LICs. Subsequently, the focus shifts towards the cutting-edge research surrounding 2D materials, including graphene, MXene, transition-metal dichalcogenides, and transition-metal oxides. The review further elaborates on the typical applications of these 2D materials within LIC frameworks, highlighting their unique properties and contributions to enhanced energy storage solutions. In conclusion, the discussion addresses the significant challenges these materials encounter within LIC applications, such as scalability, cost, and integration issues, while also projecting future development prospects. It outlines both the current limitations and the potential breakthroughs that could pave the way for more advanced and efficient LIC technologies.

In recent years, multivalent metal-ion batteries (MMIBs) have garnered significant attention and research interest because of their abundant natural reserves, low cost, and high safety. However, in practical applications, owing to the high charge density of multivalent metal ions and the strong interaction between the intercalated metal ion and the cathode, the cathode exhibits low capacity and poor cycle stability. Therefore, it is crucial to explore suitable cathode materials for use in MMIBs. MXenes are novel two-dimensional materials that have developed rapidly in the field of energy storage. The current use of MXenes as cathodes in MMIBs has not yet been systematically summarized. This review summarizes the evolution and achievements of MXene-based cathodes in MMIBs, including MXenes and their derivatives, MXene/transition metal oxide composites, MXene/sulfur-based material composites, MXene/selenium-based material composites, and other MXene composites. Finally, the current challenges and future development of MXenes for advanced cathodes in MMIBs are discussed.

Since the discovery of MXenes, the family has expanded rapidly in the past decade. With their fascinating properties, including high electrical conductivity, solution processability, tunable surface functionality, and excellent mechanical properties, MXenes have garnered significant enthusiasm from the academic community and industrial relevance. The most extensively studied of the many applications for MXene-based devices is electrochemical energy storage (EES). Importantly, MXene inks allow quick yet efficient production of personal EES devices through additive manufacturing. However, there are relatively few comprehensive summaries of reports on the processing of MXene inks for EES devices. This paper provides a comprehensive review of MXene synthesis, additive manufacturing strategies and the latest advancements in the printing of MXene-based high-performance EES devices including micro-supercapacitors and batteries. Besides, the current challenges for high precision and high-performance printing technology are also discussed. This review is expected to provide valuable insights for solution processing of MXene inks and may shed light on the large-scale application of MXenes toward the next generation of wearable electronics.

Two-dimensional MXenes are being recognized as favorable supercapacitor electrode materials due to their metallic conductivity, excellent hydrophilicity, high density, and rich surface chemistry. However, layer-restacking within MXene electrodes substantially hinders the efficient utilization of the active surface and ion accessibility. Herein, a unique carbon dots (CDs) intercalated MXene film (CDs-MF) is designed by introducing gelatin within the MXene interlayers followed by carbonization. The CD intercalation can enlarge the interlayer spacing of MXene film and induce microscopic disorder, exposing the active surface and facilitating ion diffusion within the electrode. The optimal CDs-MF electrode shows exceptional capacitive performance, achieving high gravimetric/volumetric capacitances (396.4 F g^-1 at 1 A g^-1 and 1,153.2 F cm^-3 at 1 A cm^-3), superior rate capability (123.2 F g^-1 at 1,000 A g^-1), and excellent cycling stability with no capacitance decay over 100,000 cycles. Moreover, the assembled quasi-solid-state symmetric supercapacitor exhibited a maximum energy density of 21.2 Wh L^-1 and a power density of 12 kW L^-1. The device could operate efficiently under various configurations (series or parallel) and different bending angles, reflecting its promising application in flexible energy storage devices.

During mechanical energy harvesting, complicated mechanical loads are expected to be converted into electrical energy types, including compression, extension, torque, and the coupling of them. Mechanical energy harvesting evaluation is necessary, and it is normally applied by precise mechanical sensing, such as strain gauges and piezoelectric materials. The additional and changing equivalent stiffness of the sensing approach decreases the mechanical sensing precision, and then the energy harvesting evaluation is affected. This study introduces a method for torsional sensing with torsional quasi-zero stiffness (TQZS) structures by flexoelectricity. By designing the bending beam geometry, a structure with an extended TQZS range is developed, enabling enhanced mechanical and electrical performance. Within the TQZS loading range, the generated flexoelectric charges exhibit a robust linear relationship with structural deformation, providing precise monitoring capabilities for torsion-related mechanical quantities. By leveraging flexoelectric effect, the proposed structure also converts mechanical load into electrical signal, making it suitable for high-resolution sensing, helping energy harvesting applications.

To enhance the utilization of lithium-ion battery anodes, it is crucial to improve both the lithium storage stability and kinetics of transition metal sulfides. This optimization is critical for the development of battery technologies that are more efficient, durable, and environmentally sustainable. In this study, a facile electrospinning technique followed by a thermal treatment was used to fabricate a bimetallic sulfide/porous carbon fiber composite (FeS-ZnS/PCFs). Its stability was largely improved due to the buffered ability derived from its porous structure. The presence of FeS-ZnS grain boundaries fosters the generation of extra redox active sites, ultimately boosting the kinetics of lithium storage. The optimized composite material exhibits excellent stability and efficient lithium storage performance. Density functional theory calculations and kinetics analysis further clarify superior lithium storage capabilities of this material.

In the pursuit of sustainable and clean energy sources, the development of efficient electrocatalysts for hydrogen evolution reaction has gained significant attention. In this work, we synthesized single-atom Fe-doped 1T MoS₂ (sFe-1T/MoS₂) nanosheets using a one-step hydrothermal method, harnessing the synergistic effects of iron-intercalation to enhance hydrogen production through an abundance of active sites. Notably, 10 at.% sFe-1T/MoS₂ exhibited excellent hydrogen evolution reaction performance with a low onset potential of 190 mV and a Tafel slope of 55 mV/dec in acidic solution. High performance was also achieved in alkaline solutions. Additionally, these catalysts demonstrated excellent efficiency in seawater splitting. This work not only offers a cost-effective and scalable method for producing high-quality electrocatalysts but also sets a precedent for the application of this technology across various catalytic systems, marking a significant advancement in clean energy research.

Antibiotics, as emerging organic pollutants, have seriously affected the biodiversity of water and threatened mankind’s health. Currently, low charge separation efficiency and insufficient light utilization limit the application of traditional photocatalysts in antibiotic degradation. In this work, the organic photovoltaic material PM6: Y6 was incorporated into an organic photocatalyst with bulk-heterojunction, and a third component, 3,9-bis{2-methylene-[3-(1,1-dicyanomethylene)-cyclopentane-1,3-dione-(c)thiophen]}-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2’,3’-d’]-s-indaceno[1,2-b:5,6-b’]dithiophene (ITCPTC), was added to adjust the absorption spectrum of photocatalyst for efficient photodegradation of ciprofloxacin (CIP). Benefiting from excellent light utilization and effective carrier separation and transfer, the catalyst exhibited excellent photocatalytic performance, achieving a 90%/99% degradation rate of CIP within 30/60 min under simulated sunlight irradiation (~79 mW/cm²). Besides, the catalyst still exhibited good photocatalytic performance after multiple cycles of use. By Electron Spin Resonance analysis, the active species for photocatalytic degradation of CIP were mainly holes (h⁺) and superoxide radicals (·O₂^-). Designing photocatalysts with a wider light absorption range and better charge separation is a feasible idea to achieve better photocatalytic performance. It is anticipated that this work could enhance the understanding of modification strategies for ternary organic semiconductors and expand the application of photocatalysis in environmental pollution control and remediation.

Tritium, a radioactive isotope of hydrogen, is exceptionally rare and valuable. The safe storage, controlled release and efficient capture of tritium are subject to focused research in the International Thermonuclear Experimental Reactor. However, the application of an efficient tritium-getter material remains a critical challenge. Zr₂Fe alloys exhibit a strong ability to absorb low-concentration hydrogen isotopes, but their practicability suffers from disproportionation reaction. Yet, the essential de-/hydrogenation performances and disproportionation mechanism of Zr₂Fe are inconclusive. Here, we designed a comprehensive series of measurements that demonstrate the ultra-low hydrogenation equilibrium pressure (2.68 × 10^-8 Pa at 25 °C) and unique hydrogen-interacted phase transitions in Zr₂Fe-H systems. Further kinetic and thermodynamic analyses reveal the causative reasons for disproportionation and determine the triggering temperature of the disproportionation reaction to be 375 °C in static hydrogen environments. Utilizing inversion of the Van't Hoff equation, higher-temperature hydrogen absorption models of Zr₂Fe are developed, supporting a solution to the inaccuracy and inseparability of the general de-/hydrogenation and disproportionation, thereby verifying the unique disproportionation route (Zr₂Fe/Zr₂FeH_x + H₂ → ZrFe₂ + ZrH₂). Combined with the density functional theory (DFT) calculations, the de-/hydrogenation and disproportionation mechanisms and their interrelation can be explained in depth. This work supports the exploration and modification of the Zr₂Fe-H and other metal hydride storage systems in future studies.

Dendrite growth during the continuous charge/discharge process is a serious problem that leads to internal short circuits in aqueous zinc-ion batteries. Herein, a multifunctional zinc silicate polymer lithium polysilicate (LSO) was proposed to address the issues. LSO can prevent direct contact between electrolytes and zinc anodes, thereby suppressing severe dendrite growth. Its mechanically stable structure can restrain the stress release to further stabilize the electrode. In addition, LSO is chemically bonded to zinc anodes to ensure superior overall stability compared to other surface coatings. Moreover, LSO anodes exhibit outstanding electrolyte wettability and corrosion resistance, with strong adhesion properties. In-situ optical microscopy observation demonstrates its stability during charge/discharge process. Symmetrical cells using the Zn-LSO anode exhibited long cycling life of 833, 455, 344, and 260 h with low overpotentials of 66, 80, 118, and 141 mV at current densities of 0.5, 1, 3 and 5 mA cm^-2, respectively. Full cells coupled with a MnO₂ cathode showed a high-capacity reversibility of up to 234 mAh g^-1 and outstanding rate performance at different current densities. This study demonstrates that LSO coating is a promising method for enhancing the electrochemical performance of zinc-ion batteries.