Defect‐Tailoring Mediated Electron–Hole Separation in Single‐Unit‐Cell Bi3O4Br Nanosheets for Boosting Photocatalytic Hydrogen Evolution and Nitrogen Fixation

Solar photocatalysis is a potential solution to satisfying energy demand and its resulting environmental impact. However, the low electron–hole separation efficiency in semiconductors has slowed the development of this technology. The effect of defects on electron–hole separation is not always clear. A model atomically thin structure of single‐unit‐cell Bi₃O₄Br nanosheets with surface defects is proposed to boost photocatalytic efficiency by simultaneously promoting bulk‐ and surface‐charge separation. Defect‐rich single‐unit‐cell Bi₃O₄Br displays 4.9 and 30.9 times enhanced photocatalytic hydrogen evolution and nitrogen fixation activity, respectively, than bulk Bi₃O₄Br. After the preparation of single‐unit‐cell structure, the bismuth defects are controlled to tune the oxygen defects. Benefiting from the unique single‐unit‐cell architecture and defects, the local atomic arrangement and electronic structure are tuned so as to greatly increase the charge separation efficiency and subsequently boost photocatalytic activity. This strategy provides an accessible pathway for next‐generation photocatalysts.     

Sulfur‐Deficient Bismuth Sulfide/Nitrogen‐Doped Carbon Nanofibers as Advanced Free‐Standing Electrode for Asymmetric Supercapacitors

The use of free‐standing carbon‐based hybrids plays a crucial role to help fulfil ever‐increasing energy storage demands, but is greatly hindered by the limited number of active sites for fast charge adsorption/desorption processes. Herein, an efficient strategy is demonstrated for making defect‐rich bismuth sulfides in combination with surface nitrogen‐doped carbon nanofibers (dr‐Bi₂S₃/S‐NCNF) as flexible free‐standing electrodes for asymmetric supercapacitors. The dr‐Bi₂S₃/S‐NCNF composite exhibits superior electrochemical performances with an enhanced specific capacitance of 466 F g^?1 at a discharge current density of 1 A g^?1. The high performance of dr‐Bi₂S₃/S‐NCNF electrodes originates from its hierarchical structure of nitrogen‐doped carbon nanofibers with well‐anchored defect‐rich bismuth sulfides nanostructures. As modeled by density functional theory calculation, the dr‐Bi₂S₃/S‐NCNF electrodes exhibit a reduced OH^? adsorption energy of ‐3.15 eV, compared with that (–3.06 eV) of defect‐free bismuth sulfides/surface nitrogen‐doped carbon nanofiber (df‐Bi₂S₃/S‐NCNF). An asymmetric supercapacitor is further fabricated by utilizing dr‐Bi₂S₃/S‐NCNF hybrid as the negative electrode and S‐NCNF as the positive electrode. This composite exhibits a high energy density of 22.2 Wh kg^?1 at a power density of 677.3 W kg^?1. This work demonstrates a feasible strategy to construct advanced metal sulfide‐based free‐standing electrodes by incorporating defect‐rich structures using surface engineering principles.     

CO2 Nanoenrichment and Nanoconfinement in Cage of Imine Covalent Organic Frameworks for High‐Performance CO2 Cathodes in Li‐CO2 Batteries

The Li‐CO₂ battery is an emerging green energy technology coupling CO₂ capture and conversion. The main drawback of present Li‐CO₂ batteries is serious polarization and poor cycling caused by random deposition of lithium ions and big insulated Li₂CO₃ formation on the cathode during discharge. Herein, covalent organic frameworks (COF) are identified as the porous catalyst in the cathode of Li‐CO₂ batteries for the first time. Graphene@COF is fabricated, graphene with thin and uniform imine COF loading, to enrich and confine CO₂ in the nanospaces of micropores. The discharge voltage is raised by higher local CO₂ concentration, which is predicted by the Nernst equation and realized by CO₂ nanoenrichment. Moreover, uniform lithium ion deposition directed by the graphene@COF nanoconfined CO₂ can produce smaller Li₂CO₃ particles, leading to easier Li₂CO₃ decomposition and thus lower charge voltage. The graphene@COF cathode with 47.5% carbon content achieves a discharge capacity of 27833 mAh g^?1 at 75 mA g^?1, while retaining a low charge potential of 3.5 V at 0.5 A g^?1 for 56 cycles.     

Self‐Assembled Nickel Pyrophosphate‐Decorated Amorphous Bimetal Hydroxides 2D‐on‐2D Nanostructure for High‐Energy Solid‐State Asymmetric Supercapacitor

To obtain a supercapacitor with a remarkable specific capacitance and rate performance, a cogent design and synthesis of the electrode material containing abundant active sites is necessary. In present work, a scalable strategy is developed for preparing 2D‐on‐2D nanostructures for high‐energy solid‐state asymmetric supercapacitors (ASCs). The self‐assembled vertically aligned microsheet‐structured 2D nickel pyrophosphate (Ni₂P₂O₇) is decorated with amorphous bimetallic nickel cobalt hydroxide (NiCo‐OH) to form a 2D‐on‐2D nanostructure arrays electrode. The resulting Ni₂P₂O₇/NiCo‐OH 2D‐on‐2D array electrode exhibits peak specific capacity of 281 mA hg^?1 (4.3 F cm^?2), excellent rate capacity, and cycling stability over 10 000 charge–discharge cycles in the positive potential range. The excellent electrochemical features can be attributed to the high electrical conductivity and 2D layered structure of Ni₂P₂O₇ along with the Faradic capacitance of the amorphous NiCo‐OH nanosheets. The constructed Ni₂P₂O₇/NiCo‐OH//activated carbon based solid‐state ASC cell operates in a high voltage window of 1.8 V with an energy density of 78 Wh kg^?1 (1.065 mWh cm^?3) and extraordinary cyclic stability over 10 000 charge–discharge cycles with excellent energy efficiency (75%–80%) over all current densities. The excellent electrochemical performance of the prepared electrode and solid‐state ASC device offers a favorable and scalable pathway for developing advanced electrodes.     

A Long‐Cycle‐Life Lithium–CO2 Battery with Carbon Neutrality

Lithium–CO₂ batteries are attractive energy‐storage systems for fulfilling the demand of future large‐scale applications such as electric vehicles due to their high specific energy density. However, a major challenge with Li–CO₂ batteries is to attain reversible formation and decomposition of the Li₂CO₃ and carbon discharge products. A fully reversible Li–CO₂ battery is developed with overall carbon neutrality using MoS₂ nanoflakes as a cathode catalyst combined with an ionic liquid/dimethyl sulfoxide electrolyte. This combination of materials produces a multicomponent composite (Li₂CO₃/C) product. The battery shows a superior long cycle life of 500 for a fixed 500 mAh g^?1 capacity per cycle, far exceeding the best cycling stability reported in Li–CO₂ batteries. The long cycle life demonstrates that chemical transformations, making and breaking covalent C? O bonds can be used in energy‐storage systems. Theoretical calculations are used to deduce a mechanism for the reversible discharge/charge processes and explain how the carbon interface with Li₂CO₃ provides the electronic conduction needed for the oxidation of Li₂CO₃ and carbon to generate the CO₂ on charge. This achievement paves the way for the use of CO₂ in advanced energy‐storage systems.     

Metallic Cobalt–Carbon Composite as Recyclable and Robust Magnetic Photocatalyst for Efficient CO2 Reduction

CO₂ conversion into value‐added chemical fuels driven by solar energy is an intriguing approach to address the current and future demand of energy supply. Currently, most reported surface‐sensitized heterogeneous photocatalysts present poor activity and selectivity under visible light irradiation. Here, photosensitized porous metallic and magnetic 1200 Co C composites (PMMCoCC‐1200) are coupled with a [Ru(bpy)₃]Cl₂ photosensitizer to efficiently reduce CO₂ under visible‐light irradiation in a selective and sustainable way. As a result, the CO production reaches a high yield of 1258.30 µL with selectivity of 64.21% in 6 h, superior to most reported heterogeneous photocatalysts. Systematic investigation demonstrates that the central metal cobalt is the active site for activating the adsorbed CO₂ molecules and the surficial graphite carbon coating on cobalt metal is crucial for transferring the electrons from the triplet metal‐to‐ligand charge transfer of the photosensitizer Ru(bpy)₃²⁺, which gives rise to significant enhancement for CO₂ reduction efficiency. The fast electron injection from the excited Ru(bpy)₃²⁺ to PMMCoCC‐1200 and the slow backward charge recombination result in a long‐lived, charge‐separated state for CO₂ reduction. More impressively, the long‐time stability and easy magnetic recycling ability of this metallic photocatalyst offer more benefits to the photocatalytic field.     

Synergy-Compensation Effect of Ferroelectric Polarization and Cationic Vacancy Collaboratively Promoting CO2 Photoreduction

Photocatalytic CO₂ reduction is severely limited by the rapid recombination of photo-generated charges and insufficient reactive sites. Creating electric field and defects are effective strategies to inhibit charge recombination and enrich catalytic sites, respectively. Herein, a coupled strategy of ferroelectric poling and cationic vacancy is developed to achieve high-performance CO₂ photoreduction on ferroelectric Bi₂MoO₆, and their interesting synergy-compensation relationship is first disclosed. Corona poling increases the remnant polarization of Bi₂MoO₆ to enhance the intrinsic electric field for promoting charge separation, while it decreases the CO₂ adsorption. The introduced Mo vacancy (V_Mo) facilitates the adsorption and activation of CO₂, and surface charge separation by creating local electric field. Unfortunately, V_Mo largely reduces the remnant polarization intensity. Coupling poling and V_Mo not only integrate their advantages, resulting in an approximately sevenfold increased surface charge transfer efficiency, but also compensate for their shortcomings, for example, V_Mo largely alleviates the negative effects of ferroelectric poling on CO₂ adsorption. In the absence of co-catalyst or sacrificial agent, the poled Bi₂MoO₆ with V_Mo exhibits a superior CO₂-to-CO evolution rate of 19.75 µmol g⁻¹ h⁻¹, ≈8.4 times higher than the Bi₂MoO₆ nanosheets. This work provides new ideas for exploring the role of polarization and defects in photocatalysis.     

Mineral‐Templated 3D Graphene Architectures for Energy‐Efficient Electrodes

3D graphene networks have shown extraordinary promise for high‐performance electrochemical devices. Herein, the chemical vapor deposition synthesis of a highly porous 3D graphene foam (3D‐GF) using naturally abundant calcined Iceland crystal as the template is reported. Intriguingly, the Iceland crystal transforms to CaO monolith with evenly distributed micro/meso/macropores through the releasing of CO₂ at high temperature. Meanwhile, the hierarchical structure of the calcined template could be easily tuned under different calcination conditions. By precisely inheriting fine structure from the templates, the as‐prepared 3D‐GF possesses a tunable hierarchical porosity and low density. Thus, the hierarchical pores offer space for guest hybridization and provide an efficient pathway for ion/charge transport in typical energy conversion/storage systems. The 3D‐GF skeleton electrode hybridized with Ni(OH)₂/Co(OH)₂ through an optimal electrodeposition condition exhibits a high specific capacitance of 2922.2 F g⁻¹ at a scan rate of 10 mV s⁻¹, and 2138.4 F g⁻¹ at a discharge current density of 3.1 A g⁻¹. The hybrid 3D‐GF symmetry supercapacitor shows a high energy density of 83.0 Wh kg⁻¹ at a power density of 1011.3 W kg⁻¹ and 31.4 Wh kg⁻¹ at a high power density of 18 845.2 W kg⁻¹. The facile fabrication process enables the mass production of hierarchical porous 3D‐GF for high‐performance supercapacitors.     

Metabolizable Ultrathin Bi2Se3 Nanosheets in Imaging‐Guided Photothermal Therapy

Poly(vinylpyrrolidone)‐encapsulated Bi₂Se₃ nanosheets with a thickness of 1.7 nm and diameter of 31.4 nm are prepared by a solution method. Possessing an extinction coefficient of 11.5 L g^?1 cm^?1 at 808 nm, the ultrathin Bi₂Se₃ nanosheets boast a high photothermal conversion efficiency of 34.6% and excellent photoacoustic performance. After systemic administration, the Bi₂Se₃ nanosheets with the proper size and surface properties accumulate passively in tumors enabling efficient photoacoustic imaging of the entire tumors to facilitate photothermal cancer therapy. In vivo biodistribution studies reveal that they are expelled from the body efficiently after 30 d. The ultrathin Bi₂Se₃ nanosheets have large clinical potential as metabolizable near‐infrared‐triggered theranostic agents.     

H+‐Insertion Boosted α‐MnO2 for an Aqueous Zn‐Ion Battery

Rechargeable Zn/MnO₂ batteries using mild aqueous electrolytes are attracting extensive attention due to their low cost, high safety, and environmental friendliness. However, the charge‐storage mechanism involved remains a topic of controversy so far. Also, the practical energy density and cycling stability are still major issues for their applications. Herein, a free‐standing α‐MnO₂ cathode for aqueous zinc‐ion batteries (ZIBs) is directly constructed with ultralong nanowires, leading to a rather high energy density of 384 mWh g^?1 for the entire electrode. Greatly, the H⁺/Zn²⁺ coinsertion mechanism of α‐MnO₂ cathode for aqueous ZIBs is confirmed by a combined analysis of in situ X‐ray diffractometry, ex situ transmission electron microscopy, and electrochemical methods. More interestingly, the Zn²⁺‐insertion is found to be less reversible than H⁺‐insertion in view of the dramatic capacity fading occurring in the Zn²⁺‐insertion step, which is further evidenced by the discovery of an irreversible ZnMn₂O₄ layer at the surface of α‐MnO₂. Hence, the H⁺‐insertion process actually plays a crucial role in maintaining the cycling performance of the aqueous Zn/α‐MnO₂ battery. This work is believed to provide an insight into the charge‐storage mechanism of α‐MnO₂ in aqueous systems and paves the way for designing aqueous ZIBs with high energy density and long‐term cycling ability.     

A Highly Reversible Long‐Life Li–CO2 Battery with a RuP2‐Based Catalytic Cathode

Rechargeable Li–CO₂ batteries have attracted worldwide attention due to the capability of CO₂ capture and superhigh energy density. However, they still suffer from poor cycling performance and huge overpotential. Thus, it is essential to explore highly efficient catalysts to improve the electrochemical performance of Li–CO₂ batteries. Here, phytic acid (PA)‐cross‐linked ruthenium complexes and melamine are used as precursors to design and synthesize RuP₂ nanoparticles highly dispersed on N, P dual‐doped carbon films (RuP₂‐NPCFs), and the obtained RuP₂‐NPCF is further applied as the catalytic cathode for Li–CO₂ batteries. RuP₂ nanoparticles that are uniformly deposited on the surface of NPCF show enhanced catalytic activity to decompose Li₂CO₃ at low charge overpotential. In addition, the NPCF its with porous structure in RuP₂‐NPCF provides superior electrical conductivity, high electrochemical stability, and enough ion/electron and space for the reversible reaction in Li–CO₂ batteries. Hence, the RuP₂‐NPCF cathode delivers a superior reversible discharge capacity of 11951 mAh g^?1, and achieves excellent cyclability for more than 200 cycles with low overpotentials (<1.3 V) at the fixed capacity of 1000 mAh g^?1. This work paves a new way to design more effective catalysts for Li–CO₂ batteries.     

Seed‐Assisted Growth for Low‐Temperature‐Processed All‐Inorganic CsPbIBr2 Solar Cells with Efficiency over 10%

All‐inorganic CsPbIBr₂ perovskite has recently received growing attention due to its balanced band gap and excellent environmental stability. However, the requirement of high‐temperature processing limits its application in flexible devices. Herein, a low‐temperature seed‐assisted growth (SAG) method for high‐quality CsPbIBr₂ perovskite films through reducing the crystallization temperature by introducing methylammonium halides (MAX, X = I, Br, Cl) is demonstrated. The mechanism is attributed to MA cation based perovskite seeds, which act as nuclei lowering the formation energy of CsPbIBr₂ during the annealing treatment. It is found that methylammonium bromide treated perovskite (Pvsk‐Br) film fabricated at low temperature (150 °C) shows micrometer‐sized grains and superior charge dynamic properties, delivering a device with an efficiency of 10.47%. Furthermore, an efficiency of 11.1% is achieved for a device based on high‐temperature (250 °C) processed Pvsk‐Br film via the SAG method, which presents the highest reported efficiency for inorganic CsPbIBr₂ solar cells thus far.     

Hierarchical Porous O‐Doped g‐C3N4 with Enhanced Photocatalytic CO2 Reduction Activity

Artificial photosynthesis of hydrocarbon fuels by utilizing solar energy and CO₂ is considered as a potential route for solving ever‐increasing energy crisis and greenhouse effect. Herein, hierarchical porous O‐doped graphitic carbon nitride (g‐C₃N₄) nanotubes (OCN‐Tube) are prepared via successive thermal oxidation exfoliation and curling‐condensation of bulk g‐C₃N₄. The as‐prepared OCN‐Tube exhibits hierarchically porous structures, which consist of interconnected multiwalled nanotubes with uniform diameters of 20–30 nm. The hierarchical OCN‐Tube shows excellent photocatalytic CO₂ reduction performance under visible light, with methanol evolution rate of 0.88 µmol g^?1 h^?1, which is five times higher than bulk g‐C₃N₄ (0.17 µmol g^?1 h^?1). The enhanced photocatalytic activity of OCN‐Tube is ascribed to the hierarchical nanotube structure and O‐doping effect. The hierarchical nanotube structure endows OCN‐Tube with higher specific surface area, greater light utilization efficiency, and improved molecular diffusion kinetics, due to the more exposed active edges and multiple light reflection/scattering channels. The O‐doping optimizes the band structure of g‐C₃N₄, resulting in narrower bandgap, greater CO₂ affinity, and uptake capacity as well as higher separation efficiency of photogenerated charge carriers. This work provides a novel strategy to design hierarchical g‐C₃N₄ nanostructures, which can be used as promising photocatalyst for solar energy conversion.     

Ni‐Nanocluster Modified Black TiO2 with Dual Active Sites for Selective Photocatalytic CO2 Reduction

One of the key challenges in artificial photosynthesis is to design a photocatalyst that can bind and activate the CO₂ molecule with the smallest possible activation energy and produce selective hydrocarbon products. In this contribution, a combined experimental and computational study on Ni‐nanocluster loaded black TiO₂ (Ni/TiO_2[Vo]) with built‐in dual active sites for selective photocatalytic CO₂ conversion is reported. The findings reveal that the synergistic effects of deliberately induced Ni nanoclusters and oxygen vacancies provide (1) energetically stable CO₂ binding sites with the lowest activation energy (0.08 eV), (2) highly reactive sites, (3) a fast electron transfer pathway, and (4) enhanced light harvesting by lowering the bandgap. The Ni/TiO_2[Vo] photocatalyst has demonstrated highly selective and enhanced photocatalytic activity of more than 18 times higher solar fuel production than the commercial TiO₂ (P‐25). An insight into the mechanisms of interfacial charge transfer and product formation is explored.     

A High‐Energy‐Density Hybrid Supercapacitor with P‐Ni(OH)2@Co(OH)2 Core–Shell Heterostructure and Fe2O3 Nanoneedle Arrays as Advanced Integrated Electrodes

Transition metal hydro/oxides (TMH/Os) are treated as the most promising alternative supercapacitor electrodes thanks to their high theoretical capacitance due to the various oxidation states and abundant cheap resources of TMH/Os. However, the poor conductivity and logy reaction kinetics of TMH/Os severely restrict their practical application. Herein, hierarchical core–shell P‐Ni(OH)₂@Co(OH)₂ micro/nanostructures are in situ grown on conductive Ni foam (P‐Ni(OH)₂@Co(OH)₂/NF) through a facile stepwise hydrothermal process. The unique heterostructure composed of P‐Ni(OH)₂ rods and Co(OH)₂ nanoflakes boost the charge transportation and provide abundant active sites when used as the intergrated cathode for supercapacitors. It delivers an ultrahigh areal specific capacitance of 4.4 C cm^?2 at 1 mA cm^?2 and the capacitance can maintain 91% after 10 000 cycles, showing an ultralong cycle life. Additionally, a hybrid supercapacitor composed with P‐Ni(OH)₂@Co(OH)₂/NF cathode and Fe₂O₃/CC anode shows a wider voltage window of 1.6 V, a remarkable energy density of 0.21 mWh cm^?2 at the power density of 0.8 mW cm^?2, and outstanding cycling stability with about 81% capacitance retention after 5000 cycles. This innovative study not only supplies a newfashioned electronic apparatus with high‐energy density and cycling stability but offers a fresh reference and enlightenment for synthesizing advanced integrated electrodes for high‐performance hybrid supercapacitors.     

Polyhydroxylated Metallofullerenols Stimulate IL‐1β Secretion of Macrophage through TLRs/MyD88/NF‐κB Pathway and NLRP3 Inflammasome Activation

Polyhydroxylated fullerenols especially gadolinium endohedral metallofullerenols (Gd@C₈₂(OH)₂₂) are shown as a promising agent for antitumor chemotherapeutics and good immunoregulatory effects with low toxicity. However, their underlying mechanism remains largely unclear. We found for the first time the persistent uptake and subcellular distribution of metallofullerenols in macrophages by taking advantages of synchrotron‐based scanning transmission X‐ray microscopy (STXM) with high spatial resolution of 30 nm. Gd@C₈₂(OH)₂₂ can significantly activate primary mouse macrophages to produce pro‐inflammatory cytokines like IL‐1β. Small interfering RNA (siRNA) knockdown shows that NLRP3 in?ammasomes, but not NLRC4, participate in fullerenol‐induced IL‐1β production. Potassium efflux, activation of P2X₇ receptor and intracellular reactive oxygen speciesare also important factors required for fullerenols‐induced IL‐1β release. Stronger NF‐κB signal triggered by Gd@C₈₂(OH)₂₂ is in agreement with higher pro‐IL‐1β expression than C₆₀(OH)₂₂. Interestingly, TLR4/MyD88 pathway but not TLR2 mediates IL‐1β secretion in Gd@C₈₂(OH)₂₂ exposure confirmed by macrophages from MyD88^?/?/TLR4^?/?/TLR2^?/? knockout mice, which is different from C₆₀(OH)₂₂. Our work demonstrated that fullerenols can greatly activate macrophage and promote IL‐1β production via both TLRs/MyD88/NF‐κB pathway and NLRP3 inflammasome activation, while Gd@C₈₂(OH)₂₂ had stronger ability C₆₀(OH)₂₂ due to the different electron affinity on the surface of carbon cage induced by the encaged gadolinium ion.     

2D Porous TiO2 Single‐Crystalline Nanostructure Demonstrating High Photo‐Electrochemical Water Splitting Performance

Porous single crystals are promising candidates for solar fuel production owing to their long range charge diffusion length, structural coherence, and sufficient reactive sites. Here, a simple template‐free method of growing a selectively branched, 2D anatase TiO₂ porous single crystalline nanostructure (PSN) on fluorine‐doped tin oxide substrate is demonstrated. An innovative ion exchange–induced pore‐forming process is designed to successfully create high porosity in the single‐crystalline nanostructure with retention of excellent charge mobility and no detriment to crystal structure. PSN TiO₂ film delivers a photocurrent of 1.02 mA cm^?2 at a very low potential of 0.4 V versus reversible hydrogen electrode (RHE) for photo‐electrochemical water splitting, closing to the theoretical value of TiO₂ (1.12 mA cm^?2). Moreover, the current–potential curve featuring a small potential window from 0.1 to 0.4 V versus RHE under one‐sun illumination has a near‐ideal shape predicted by the Gartner Model, revealing that the charge separation and surface reaction on the PSN TiO₂ photoanode are very efficient. The photo‐electrochemical water splitting performance of the films indicates that the ion exchange–assisted synthesis strategy is effective in creating large surface area and single‐crystalline porous photoelectrodes for efficient solar energy conversion.     

Engineering 2D Nanofluidic Li‐Ion Transport Channels for Superior Electrochemical Energy Storage

Rational surface engineering of 2D nanoarchitectures‐based electrode materials is crucial as it may enable fast ion transport, abundant‐surface‐controlled energy storage, long‐term structural integrity, and high‐rate cycling performance. Here we developed the stacked ultrathin Co₃O₄ nanosheets with surface functionalization (SUCNs‐SF) converted from layered hydroxides with inheritance of included anion groups (OH^?, NO₃^?, CO₃^2?). Such stacked structure establishes 2D nanofluidic channels offering extra lithium storage sites, accelerated Li‐ion transport, and sufficient buffering space for volume change during electrochemical processes. Tested as an anode material, this unique nanoarchitecture delivers high specific capacity (1230 and 1011 mAh g^?1 at 0.2 and 1 A g^?1, respectively), excellent rate performance, and long cycle capability (1500 cycles at 5 A g^?1). The demonstrated advantageous features by constructing 2D nanochannels in nonlayered materials may open up possibilities for designing high‐power lithium ion batteries.     

Heterogeneous Single‐Atom Catalyst for Visible‐Light‐Driven High‐Turnover CO2 Reduction: The Role of Electron Transfer

Visible‐light‐driven conversion of CO₂ into chemical fuels is an intriguing approach to address the energy and environmental challenges. In principle, light harvesting and catalytic reactions can be both optimized by combining the merits of homogeneous and heterogeneous photocatalysts; however, the efficiency of charge transfer between light absorbers and catalytic sites is often too low to limit the overall photocatalytic performance. In this communication, it is reported that the single‐atom Co sites coordinated on the partially oxidized graphene nanosheets can serve as a highly active and durable heterogeneous catalyst for CO₂ conversion, wherein the graphene bridges homogeneous light absorbers with single‐atom catalytic sites for the efficient transfer of photoexcited electrons. As a result, the turnover number for CO production reaches a high value of 678 with an unprecedented turnover frequency of 3.77 min^?1, superior to those obtained with the state‐of‐the‐art heterogeneous photocatalysts. This work provides fresh insights into the design of catalytic sites toward photocatalytic CO₂ conversion from the angle of single‐atom catalysis and highlights the role of charge kinetics in bridging the gap between heterogeneous and homogeneous photocatalysts.     

Boron Phosphide Nanoparticles: A Nonmetal Catalyst for High‐Selectivity Electrochemical Reduction of CO2 to CH3OH

Electrocatalysis has emerged as an attractive way for artificial CO₂ fixation to CH₃OH, but the design and development of metal‐free electrocatalyst for highly selective CH₃OH formation still remains a key challenge. Here, it is demonstrated that boron phosphide nanoparticles perform highly efficiently as a nonmetal electrocatalyst toward electrochemical reduction of CO₂ to CH₃OH with high selectivity. In 0.1 m KHCO₃, this catalyst achieves a high Faradaic efficiency of 92.0% for CH₃OH at ?0.5 V versus reversible hydrogen electrode. Density functional theory calculations reveal that B and P synergistically promote the binding and activation of CO₂, and the rate‐determining step for the CO₂ reduction reaction is dominated by *CO + *OH to *CO + *H₂O process with free energy change of 1.36 eV. In addition, CO and CH₂O products are difficultly generated on BP (111) surface, which is responsible for the high activity and selectivity of the CO₂‐to‐CH₃OH conversion process.