Carbon Energy最新文献

The robustness of single-atom catalysts (SACs) is a critical concern for practical applications, especially for thermal catalysis at elevated temperatures under reductive conditions. In this study, a laser solid-phase synthesis technique is reported to fabricate atom-nanoisland-sea structured SACs for the first time. The resultant catalysts are constructed by Pt single atoms on In₂O₃ supported by Co₃O₄ nanoislands uniformly dispersed in the sea of reduced graphene oxide. The laser process, with a maximum temperature of 2349 K within ~100 μs, produced abundant oxygen vacancies (up to 70.8%) and strong interactions between the Pt single atoms and In₂O₃. The laser-synthesized catalysts exhibited a remarkable catalytic performance towards CO₂ hydrogenation to methanol at 300°C with a CO₂ conversion of 30.3%, methanol selectivity of 90.6% and exceptional stability over 48 h without any deactivation, outperforming most of the relevant catalysts reported in the literature. Characterization of the spent catalysts after testing for 48 h reveals that the Pt single atoms were retained and the oxygen vacancies remained almost unchanged. In situ diffuse reflectance infrared Fourier transform spectrum was conducted to establish the reaction mechanism supported by the density functional theory simulations. It is believed that this laser synthesis strategy opens a new avenue towards rapidly manufacturing highly active and robust thermal SACs.

Considering the growing pre-lithiation demand for high-performance Si-based anodes and consequent additional costs caused by the strict pre-lithiation environment, developing effective and environmentally stable pre-lithiation additives is a challenging research hotspot. Herein, interfacial engineered multifunctional Li₁₃Si₄@perfluoropolyether (PFPE)/LiF micro/nanoparticles are proposed as anode pre-lithiation additives, successfully constructed with the hybrid interface on the surface of Li₁₃Si₄ through PFPE-induced nucleophilic substitution. The synthesized multifunctional Li₁₃Si₄@PFPE/LiF realizes the integration of active Li compensation, long-term chemical structural stability in air, and solid electrolyte interface (SEI) optimization. In particular, the Li₁₃Si₄@PFPE/LiF with a high pre-lithiation capacity (1102.4 mAh g⁻¹) is employed in the pre-lithiation Si-based anode, which exhibits a superior initial Coulombic efficiency of 102.6%. Additionally, in situ X-ray diffraction/Raman, density functional theory calculation, and finite element analysis jointly illustrate that PFPE-predominant hybrid interface with modulated abundant highly electronegative F atoms distribution reduces the water adsorption energy and oxidation kinetics of Li₁₃Si₄@PFPE/LiF, which delivers a high pre-lithiation capacity retention of 84.39% after exposure to extremely moist air (60% relative humidity). Intriguingly, a LiF-rich mechanically stable bilayer SEI is constructed on anodes through a pre-lithiation-driven regulation for the behavior of electrolyte decomposition. Benefitting from pre-lithiation via multifunctional Li₁₃Si₄@PFPE/LiF, the full cell and pouch cell assembled with pre-lithiated anodes operate with long-time stability of 86.5% capacity retention over 200 cycles and superior energy density of 549.9 Wh kg^–1, respectively. The universal multifunctional pre-lithiation additives provide enlightenment on promoting large-scale applications of pre-lithiation on commercial high-energy-density and long-cycle-life lithium-ion batteries.

Hydrogen peroxide (H₂O₂) is an eco-friendly chemical with widespread industrial applications. However, the commercial anthraquinone process for H₂O₂ production is energy-intensive and environmentally harmful, highlighting the need for more sustainable alternatives. The electrochemical production of H₂O₂ via the two-electron water oxidation reaction (2e⁻ WOR) presents a promising route but is often hindered by low efficiency and selectivity, due to the competition with the oxygen evolution reaction. In this study, we employed high-throughput computational screening and microkinetic modeling to design a series of efficient 2e⁻ WOR electrocatalysts from a library of 240 single-metal-embedded nitrogen heterocycle aromatic molecules (M-NHAMs). These catalysts, primarily comprising post-transition metals, such as Cu, Ni, Zn, and Pd, exhibit high activity for H₂O₂ conversion with a limiting potential approaching the optimal value of 1.76 V. Additionally, they exhibit excellent selectivity, with Faradaic efficiencies exceeding 80% at overpotentials below 300 mV. Structure-performance analysis reveals that the d-band center and magnetic moment of the metal center correlated strongly with the oxygen adsorption free energy ($��\; ��{�∆�\; �G�}_{O^{*}}��$), suggesting these parameters as key catalytic descriptors for efficient screening and performance optimization. This study contributes to the rational design of highly efficient and selective electrocatalysts for electrochemical production of H₂O₂, offering a sustainable solution for green energy and industrial applications.

Cu-based metal-organic frameworks (Cu-MOFs) electrocatalysts are promising for CO₂ reduction reactions (CO₂RR) to produce valuable C₂₊ products. However, designing suitable active sites in Cu-MOFs remains challenging due to their inherent structural instability during CO₂RR. Here we propose a synergistic strategy through thermal annealing and electrochemical-activation process for in-situ reconstruction of the pre-designed Cu-MOFs to produce abundant partially oxidized Cu (Cu^δ+) active species. The optimized MOF-derived Cu^δ+ electrocatalyst demonstrates a highly selective production of C₂₊ products, with the Faradaic Efficiency (FE) of 78 ± 2% and a partial current density of −46 mA cm⁻² at −1.06 V_RHE in a standard H-type cell. Our findings reveal that the optimized Cu^δ+-rich surface remains stable during electrolysis and enhances surface charge transfer, leading to an increase in the concentration of *CO intermediates, thereby highly selectively producing C₂₊ compounds. This study advances the controllable formation of MOF-derived Cu^δ+-rich surfaces and strengthens the understanding of their catalytic role in CO₂RR for C₂₊ products.

Front cover image: Practical green hydrogen production requires efficient, low-cost, nontoxic materials integrated into simple device architectures. However, achieving high solar-to-hydrogen (STH) efficiency using solely earth-abundant materials in the overall device remains a critical bottleneck. In article number CEY2706, Park et al. report a solar hydrogen production system with over 10% STH efficiency under unbiased conditions. The device combines a Se-incorporated Ni3S2 electrocatalyst with a ternary bulk heterojunction organic semiconductor composed of PM6, D18, and L8-BO. Ternary absorber enables tailored photovoltage and enhanced photocurrent by suppressing non-radiative decay pathways. Effective integration of the catalyst and light absorber offers a simple and effective route for benchmark-efficiency solar hydrogen production using earth-abundant materials.

Back cover image: Large-scale green hydrogen production technologies play an important role in replacing fossil fuels. However, its cost heavily relies on non-precious metal electrocatalysts with high activity and stability under industrial conditions. In article number CEY2684, Pan et al. fabricated a Fe and Co co-incorporated nickel (oxy) hydroxide exhibits outstanding OER performance under industrial conditions. The surface-reconstructed γ-NiOOH with high valence state is the active layer, where the optimal (Fe, Co) co-incorporation tunes its electronic structure, change the potential determining step, and reduces the energy barrier, leading to ultra-high activity and stability.

Lithium metal is a compelling choice as an anode material for high-energy-density batteries, attributed to its elevated theoretical specific energy and low redox potential. Nevertheless, challenges arise due to its susceptibility to high-volume changes and the tendency for dendritic development during cycling, leading to restricted cycle life and diminished Coulombic efficiency (CE). Here, we innovatively engineered a kind of porous biocarbon to serve as the framework for a lithium metal anode, which boasts a heightened specific surface area and uniformly dispersed ZnO active sites, directly derived from metasequoia cambium. The porous structure efficiently mitigates local current density and alleviates the volume expansion of lithium. Also, incorporating the ZnO lithiophilic site notably reduces the nucleation overpotential to a mere 16 mV, facilitating the deposition of lithium in a compact form. As a result, this innovative material ensures an impressive CE of 98.5% for lithium plating/stripping over 500 cycles, a remarkable cycle life exceeding 1200 h in a Li symmetrical cell, and more than 82% capacity retention ratio after an astonishing 690 cycles in full cells. In all, such a rationally designed Li composite anode effectively mitigates volume change, enhances lithophilicity, and reduces local current density, thereby inhibiting dendrite formation. The preparation of a high-performance lithium anode frame proves the feasibility of using biocarbon in a lithium anode frame.

Metal halide perovskites exhibit excellent absorption properties, high carrier mobility, and remarkable charge transfer ability, showcasing significant potential as light harvesters in new-generation photovoltaic and optoelectronic technologies. Their development has seen unprecedented growth since their discovery. Similar to metal halide perovskite developments, perovskite quantum dots (PQDs) have demonstrated significant versatility in terms of shape, dimension, bandgap, and optical properties, making them suitable for the development of optoelectronic devices. This review discusses various fabrication methods of PQDs, delves into their degradation mechanisms, and explores strategies for enhancing their performance with their applications in a variety of technological fields. Their elevated surface-to-volume ratio highlights their importance in increasing solar cell efficiency. PQDs are also essential for increasing the performance of perovskite solar cells, photodetectors, and light-emitting diodes, which makes them indispensable for solid-state lighting applications. PQDs' unique optoelectronic characteristics make them suitable for sophisticated sensing applications, giving them greater capabilities in this field. Furthermore, PQDs' resistive switching behavior makes them a good fit for applications in memory devices. PQDs' vast potential also encompasses the fields of quantum optics and communication, especially for uses like nanolasers and polarized light detectors. Even though stability and environmental concerns remain major obstacles, research efforts are being made to actively address these issues, enabling PQDs to obtain their full potential in device applications. Simply put, understanding PQDs' real potential lies in overcoming obstacles and utilizing their inherent qualities.

The efficient and stable operation of proton exchange membrane fuel cells (PEMFCs) in practical applications can be adversely affected by various contaminants. This study delves into the impact of Cr₂(SO₄)₃ contamination on the gas diffusion layer (GDL) and PEMFC performance, systematically analyzing the physicochemical property changes and their correlation with electrochemical performance. The results indicate that after post-treatment, the GDL surface exhibited exposed carbon fibers, cracks, and large pores in the microporous layer (MPL), with a noticeable detachment of PTFE. There was a marked reduction in C and F element signals, an increase in O element signals, deposition of Cr₂(SO₄)₃, formation of C=O and C=C bonds, appearance of Cr₂(SO₄)₃ characteristic peaks, and changes in pore structure—all suggesting significant alterations in the GDL's surface morphology, structure, and chemical composition. The decline in mechanical strength and thermal stability, and increased surface roughness and resistance negatively impacted fuel cell performance. At high current densities, the emergence of water flooding increased mass transfer resistance from 0.1 Ω cm² to 1.968 Ω cm², with a maximum power density decay rate reaching 71.17%. This study reveals the significant negative impact of Cr₂(SO₄)₃ contamination on GDL and fuel cell performance, highlighting that changes in surface structure, reduced hydrophobicity, and increased mass transfer resistance are primary causes of performance degradation. The findings provide crucial insights for improving GDL materials, optimizing fuel cell manufacturing and operation processes, and addressing contamination issues in practical applications.

Sodium-ion batteries have emerged as promising candidates for next-generation large-scale energy storage systems due to the abundance of sodium resources, low solvation energy, and cost-effectiveness. Among the available cathode materials, vanadium-based sodium phosphate cathodes are particularly notable for their high operating voltage, excellent thermal stability, and superior cycling performance. However, these materials face significant challenges, including sluggish reaction kinetics, the toxicity of vanadium, and poor electronic conductivity. To overcome these limitations and enhance electrochemical performance, various strategies have been explored. These include morphology regulation via diverse synthesis routes and electronic structure optimization through metal doping, which effectively improve the diffusion of Na⁺ and electrons in vanadium-based phosphate cathodes. This review provides a comprehensive overview of the challenges associated with V-based polyanion cathodes and examines the role of morphology and electronic structure design in enhancing performance. Key vanadium-based phosphate frameworks, such as orthophosphates (Na₃V₂(PO₄)₃), pyrophosphates (NaVP₂O₇, Na₂(VO)P₂O₇, Na₇V₃(P₂O₇)₄), and mixed phosphates (Na₇V₄(P₂O₇)₄PO₄), are discussed in detail, highlighting recent advances and insights into their structure–property relationships. The design of cathode material morphology offers an effective approach to optimizing material structures, compositions, porosity, and ion/electron diffusion pathways. Simultaneously, electronic structure tuning through element doping allows for the regulation of band structures, electron distribution, diffusion barriers, and the intrinsic conductivity of phosphate compounds. Addressing the challenges associated with vanadium-based sodium phosphate cathode materials, this study proposes feasible solutions and outlines future research directions toward advancement of high-performance vanadium-based polyanion cathodes.