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Abstract Emerging energy storage devices are vital approaches towards peak carbon dioxide emissions. Zinc-ion energy storage devices (ZESDs), including zinc ion capacitors and zinc ion batteries, are being intensely pursued due to their abundant resources, economic effectiveness, high safety, and environmental friendliness. Carbon materials play their important role in the development of ZESDs, from cathode, electrolyte, to metallic Zn anode. Though thrilling development has been achieved in ZESDs, they still face the challenges of unsatisfactory capacity and kinetics for cathode, and irreversibility and low utilization rate of Zn anode. Hence, the roles of carbon materials in ZESDs are systematically discussed, starting with investigating carbons with different dimensions as cathodes and the corresponding strategies to improve their performance. Also, carbons as coatings or skeletons for other types of cathode materials are introduced. Besides, the functions of carbons in electrolyte development are explored. Further, the influence of carbon materials on Zn anode is elucidated with the corresponding operational mechanisms. Finally, an outlook for carbon materials in ZESDs is provided. We envision the presented minireview can pay way on exploring novel carbon research towards next-generation energy storage technologies.

Sodium-ion battery (SIB) is an ideal candidate for large-scale energy storage due to high abundant sodium sources, relatively high energy density, and potentially low costs. Hard carbons, as one of the most promising anodes, could deliver high plateau capacities at low potentials, which boosts the energy densities of SIBs. Their slope capacities have been demonstrated from the defect adsorption of sodium ions, while the plateau capacity depends highly on intercalation and pore filling. Nevertheless, the specific structures of sodium ions stored in hard carbons have not been clarified, namely active sites of adsorption, intercalation, and pore-filling mechanisms. Therefore, delicate synthesis methods are required to prepare hard carbons with controllable specific structures, along with elucidating the precise active sites for enhancing the Na-ion storage performance. To offer databases for future designs, we summarized the synthesis strategies of hard carbon anodes for constructing active sites of plateau capacities. Synthesis methods were highlighted with corresponding influences on the meticulous structures of hard carbons and Na-ion storage behaviors. Last but not least, perspectives were proposed for developing hard carbon anodes from the points of research and practical applications.

Highlights History and benefits of zinc ion hybrid capacitors are introduced. Carbon materials with different dimensions are developed for the cathodes. Relationship between carbon structures and capacitive performances are discussed. Current collectors and separators are firstly showcased and summarized.

Electrocatalytic hydrogenation (ECH) of organics using water as hydrogen donors has been regarded as a green organic reduction technique to replace traditional chemical reactions that use sacrificial chemicals. The development of ECH process provides potential applications in the production of value-added chemicals owing to its low energy consumption, low pollution, high safety, and superior sustainability. However, its application is limited by the low conversion rate and poor selectivity toward desired products. The efficiency of ECH can be improved by rational design of electrocatalysts. This review covers several representative electrocatalytic systems (aldehydes, ketones, phenolic organics, alkynes, and organonitrogen compounds) and summarizes different ECH mechanisms, followed by thorough discussion on the modification strategies of electrocatalysts that are currently adopted to enhance the catalytic performance. Finally, in view of the current challenges for ECH, we discuss possible future directions in the field, aiming to provide guidance to the catalyst design toward highly efficient ECH reactions over different organic feedstocks.

Abstract Compared to the commonly applied metallic ion charge carriers (e.g., Li+ and Na+), batteries using nonmetallic charge carriers (e.g., H+ and NH4+) generally have much faster kinetics and high‐rate capability thanks to the small hydrated ionic sizes and nondiffusion control topochemistry. However, the hosts for nonmetallic charge carriers are still limited. In this work, it is suggested that mixed ionic–electronic conductors can serve as a promising host for NH4+ storage. Using hexagonal tungsten oxide (h‐WO3) as an example, it is shown that the existence of ionic conductive tunnels greatly promotes the high‐rate NH4+ storage. Specifically, a much higher capacity of 82 mAh g–1 at 1 A g–1 is achieved on h‐WO3, in sharp contrast to 14 mAh g–1 of monoclinic tungsten oxide (m‐WO3). In addition, unlike layered materials, the insertion and desertion of NH4+ ions are confined within the tunnels of the h‐WO3, which minimizes the damage to the crystal structure. This leads to outstanding stability of up to 200 000 cycles with 68% capacity retention at a high current of 20 A g–1.

Titanium (Ti) and its alloys have been extensively used as implant materials in clinical practice due to their high corrosion resistance, light weight and excellent biocompatibility. However, the insufficient intrinsic osteogenic capacity of Ti and its alloys impedes bone repair and regeneration, and implant-related infection or inflammation remains the leading cause of implant failure. Bacterial infections or inflammatory diseases constitute severe threats to human health. The physicochemical properties of the material are critical to the success of clinical procedures, and the doping of Cu into Ti implants has been confirmed to be capable of enhancing the bone repair/regeneration, angiogenesis and antibacterial capability. This review outlines the recent advances in the design and preparation of Cu-doped Ti and Ti alloy implants, with a special focus on various methods, including plasma immersion implantation, magnetron sputtering, galvanic deposition, microarc oxidation and sol-gel synthesis. More importantly, the antibacterial and mechanical properties as well as the corrosion resistance and biocompatibility of Cu-doped Ti implants from different methods are systematically reviewed, and their prospects and limitations are also discussed.

Abstract Supercapacitors as a new type of energy storage devices bridging the gap between conventional capacitors and batteries have aroused widespread concern. Herein, binder-free titanium nitride (TiN) thin film electrodes for supercapacitors prepared by reactive magnetron sputtering technology are reported. The effect of N2 content on the supercapacitor performance is evaluated. A highest specific capacitance of 27.3 mF cm−2 at a current density of 1.0 mA cm−2, together with excellent cycling performance (98.2% capacitance retention after 20,000 cycles at 2.0 mA cm−2) is achieved in a 0.5 M H2SO4 aqueous electrolyte. More importantly, a symmetric supercapacitor device assembled on the basis of TiN thin films can deliver a maximum energy density of 17.6 mWh cm−3 at a current density of 0.2 mA cm−2 and a maximum power density of 10.8 W cm−3 at a current density of 2 mA cm−2 with remarkable cycling stability. As a consequence, TiN thin films demonstrate great potential as promising supercapacitor electrode materials.

Abstract Electricity generation and chemical production are both critical cornerstone for modern society. Integrating electricity output and high value chemical production in an electrochemical system is highly attractive both environmentally and sustainably. In this review, we summarize the recent advances in the development of these multifunctional devices (electrocatalytic flow batteries) that could generate both electricity and high value chemicals through rational coupling of half‐electrode reactions, covering the basic principles, device configurations, and applications. We also discuss the current challenges and suggest potential research directions.