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Regulating the electronic and geometric structures of electrocatalysts is an effective strategy to boost their catalytic properties. Herein, a coral-like nanostructure is assembled with Mo-doped Pt clusters to form a highly active catalyst toward the oxygen reduction reaction (ORR). The advantages of a Mo-doped porous skeleton, grain boundaries, and MoOx species on the Pt cluster surfaces synergistically boost the electrocatalytic performance. This unique architecture delivers 3.5- and 2.8-fold higher mass and specific activities, respectively, than commercial Pt/C. Density functional theory calculations reveal that the Mo-doped Pt clusters have an optimized Pt–O bond length of 2.110 ​Å, which weakens the adsorption energy of the intermediate O∗ to yield great ORR activity. Moreover, the catalyst shows a decay in the half-wave potential of only 8 ​mV after 10,000 cycles of accelerated durability testing. The high stability arises from the increased dissociation energy of Pt atoms and the stable architecture of the coral-like structure of clusters.

Crystal structure determines electrochemical energy storage characteristics; this is the underlying logic of material design. To date, hundreds of electrode materials have been developed to pursue superior performance. However, it remains a great challenge to understand the fundamental structure–performance relationship and achieve quantitative crystal structure design for efficient energy storage. In this review, we introduce the concept of crystal packing factor (PF), which can quantify crystal packing density. We then present and classify the typical crystal structures of attractive cathode/anode materials. Comparative PF analyses of different materials, including polymorphs, isomorphs, and others, are performed to clarify the influence of crystal packing density on energy storage performance through electronic and ionic conductivities. Notably, the practical electronic/ionic conductivities of energy storage materials are based on their intrinsic characteristics related to the PF yet are also affected by extrinsic factors. The PF provides a novel avenue for understanding the electrochemical performance of pristine materials and may offer guidance on designing better materials. Additional approaches involve size regulation, doping, carbon additives, and other methods. We also propose extended PF concepts to understand charge storage and transport behavior at different scales. Finally, we provide our insights on the major challenges and prospective solutions in this highly exciting field.

As high-energy cathode materials, conversion-type metal fluorides provide a prospective pathway for developing next-generation lithium-ion batteries. However, they suffer from severe performance decay owing to continuous structural destruction and active material dissolution upon cycling, which worsen at elevated temperatures. Here, we design a novel FeF₂ cathode with in situ polymerized solid-state electrolyte systems to enhance the cycling ability of metal fluorides at 60 ​°C. Novel FeF₂ with a mesoporous structure (meso-FeF₂) improves Li⁺ diffusion and relieves the volume change that typically occurs during the alternating conversion reactions. The structural stability of the meso-FeF₂ cathode is strengthened by an in situ polymerized solid-state electrolyte, which prevents the pulverization and ion dissolution that are inevitable for conventional liquid electrolytes. Under the double action of this in situ polymerized solid-state electrolyte and the meso-FeF₂'s mesoporous structure, the active material maintains an intact SEI layer and part of the mesoporous structure after long charge–discharge cycling, showing excellent cycling stability at high temperatures.

Although single-atom catalysts (SACs) have attracted enormous attention for their applications in the electrochemical reduction of CO₂ (CO₂RR) due to their extraordinary catalytic activity and well-defined active centers, neighboring effects and their influence on the electrochemical performance of SACs have not been well investigated. In this review, we present a summary of the neighboring effects on SACs for the CO₂RR process, where the surrounding atoms not only induce electronic modulation of the metal atom but also participate in the CO₂RR. Both theoretical and experimental studies have pointed out that the neighboring sites of the anchored metal center can provide second active/adsorption locations during the catalytic process, enhancing CO₂RR performance tremendously. This review supplies advanced insights into the significant roles and impacts of neighboring effects on the catalytic process, which also benefit the development of advanced SACs to achieve efficient electrocatalysis.

Perovskite solar cells (PSCs) have shown remarkable advancements and achieved impressive power conversion efficiencies since their initial introduction in 2012. However, challenges regarding stability, quality, and sustainability must be addressed for their successful commercial use. This review analyses the recent studies and challenges related to the operating life and end-of-life utilization of PSCs. Strategies to enhance the stability and mitigate the toxic Pb leakage in operational and recycling approaches of discarded PSCs post their end-of-life are examined to establish a viable and sustainable PSC industry. Additionally, future research directions are proposed for the advancements in the PSC industry. The goal is to ensure high efficiency as well as economic and environmental sustainability throughout the lifecycle of PSCs.

Carbon-based perovskite solar cells (C-PSCs) are promising candidates for large-scale photovoltaic applications due to their theoretical low cost and high stability. However, the fabrication of high-performance C-PSCs with large-area electrodes remains challenging. In this work, we propose a novel playdough-like graphite putty as top electrode in the perovskite devices. This electrode with soft nature can form good contact with the hole-transporting layer and the conductive substrate at room temperature by a simple pressing technique, which facilitates the fabrication of both small-area devices and perovskite solar modules. In this preliminary research, the corresponding small devices and modules can achieve efficiencies of 20.29% (∼0.15 ​cm²) and 16.01% (∼10 ​cm²), respectively. Moreover, we analyze the limitations of the optical and electrical properties of this playdough-like graphite electrode on the device performance, suggesting a direction for further improvement of C-PSCs in the future.

Developing the high biosafety, effective and wearable devices for fast wound healing is highly desired but remains a challenge. Here, we propose a “win–win co-operation” strategy to potentiate effective skin wound healing at the wound site by constructing robust and ecofriendly composite patch under opto-electric stimulation. The wearable patch is composed of ionic gel doped with Ti₃C₂T_x (MXene), which possesses good photothermal response to kill the bacteria via effective inhibition of the expression of inflammatory factors, preventing wound infection. Importantly, the composite ionogel patch is capable of providing green and on-demand electrical stimulation for wound site, guiding cell migration and proliferation by improved bioenergy and expression up-regulation of growth factor. In mice wound models, the treatment group healed ∼31% more rapidly. Mechanistically, the wearable devices could enable visual and real-time supervising treatment effect due to their good transmittance. The proposed strategy would be promising for future clinical treatment of wound healing.

Phase modulation of noble metal alloys (NMAs) is critically important in nanoscience since the distinct atomic arrangements can largely determine their physicochemical properties. However, the precise modulation of NMAs is formidably challenging, because thermodynamically stable phases are generally preferential compared to those metastable ones. Herein, we proposed a potential energy trapping strategy for phase modulation of Pd–Te alloys with solvents. Thereinto, ethylene glycol can increase the energy barrier for both Pd leaching and Te introduction, forming metastable Pd₂₀Te₇ phase. Inversely, N, N-dimethylformamide is unable to trap metastable phase, inducing the phase evolution to thermodynamically stable PdTe phase, and the precise phase modulation was realized including Pd₂₀Te₇, PdTe and PdTe₂ phases. The Pd–Te alloys displayed phase-dependent formic acid oxidation catalytic performance with PdTe phase showing the best. This work proposes a strategy for creating metastable phase with potential energy trap, which may deepen the understanding of phase engineering for noble metal-based nanocrystals.

Present photocatalysts for the synchronous cleanup of pharmaceuticals and heavy metals have several drawbacks, including inadequate reactive sites, inefficient electron–hole disassociation, and insufficient oxidation and reduction power. In this research, we sought to address these issues by using a facile solvothermal-photoreduction route to develop an innovative plasmonic S-scheme heterojunction, Au/MIL-101(Fe)/BiOBr. The screened-out Au/MIL-101(Fe)/BiOBr (AMB-2) works in a durable and high-performance manner for both Cr(VI) and norfloxacin (NOR) eradication under visible light, manifesting up to 53.3 and 2 times greater Cr(VI) and NOR abatement rates, respectively, than BiOBr. Remarkably, AMB-2's ability to remove Cr(VI) in a Cr(VI)-NOR co-existence system is appreciably better than in a sole-Cr(VI) environment; the synergy among Cr(VI), NOR, and AMB-2 results in the better utilization of photo-induced carriers, yielding a desirable capacity for decontaminating Cr(VI) and NOR synchronously. The integration of MOF-based S-scheme heterojunctions and a plasmonic effect contributes to markedly reinforced photocatalytic ability by increasing the number of active sites, augmenting the visible-light absorbance, boosting the efficient disassociation and redistribution of powerful photo-carriers, and elevating the generation of reactive substances. We provide details of the photocatalytic mechanism, NOR decomposition process, and bio-toxicity of the intermediates. This synergistic strategy of modifying S-scheme heterojunctions with a noble metal opens new horizons for devising excellent MOF-based photosystems with a plasmonic effect for environment purification.