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Aqueous zinc‐based energy storage devices have competitive advantages such as high power density, good safety, and wide source. However, because of the direct touch among zinc anode and aqueous electrolyte, dendrite growth and electrode side reactions are easy to occur in the plating and striping process, which seriously hinders the further development of aqueous zinc‐based energy storage devices. Therefore, it is urgent to solve the above problems to expand the existing energy storage devices. In this work, by adding an imidazo[1,2‐b]pyridazine (IP) electrolyte additive, the dendrites' growth and corrosion on the zinc anode surface could be effectively inhibited by the shielding‐anchoring double effects, which are verified by the comprehensive in situ and ex situ characterization techniques as well as the theoretical calculation support. Accordingly, the IP‐based electrolyte encourages extremely high stable zinc anode (cycling 2200 h at 1 mA cm−2) with high average Coulombic efficiency (98.72%). Moreover, the IP‐based Zn‐V2O5 full battery also exhibits excellent reversible capacity, reaching 160.8 mAh g−1 after 400 cycles at 2 A g−1. Through a straightforward alteration to the Zn anode surface, this study considerably enhances the use of highly stable and secure aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Designing efficient multifunctional electrocatalysts for water and urea splitting to produce green hydrogen presents a significant yet worthwhile challenge. Herein, the morphology and electronic structure of cobalt metaphosphate (Co2P4O12) by vanadium (V) doping, resulting in improved electrocatalytic activity and stability for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and urea oxidation reaction (UOR) are simultaneously regulated. Theory calculations show that V‐doped Co2P4O12 (V‐Co2P4O12) can boost the kinetics of catalytic reactions by optimizing the d‐band center of Co atoms and the binding strength of intermediates, as well as enhancing the density of states. Moreover, the doping of V into Co2P4O12 crystalline structure benefits the formation of a thicker amorphous layer during the catalytic process, which could enhance its alkaline corrosion resistance and stability. Additionally, the multilevel nanostructures of V‐Co2P4O12 provide rich active sites for catalytic reactions. As a result, a two‐electrode electrolyzer assembled by V‐doped Co2P4O12 delivers low voltages for overall water and urea splitting. The superior performance suggests that the proposed V‐doping strategy is a promising way to regulate electrocatalytic activity for catering to green electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Intelligent membranes with adaptive gating channels play a crucial role in cellular functions and separation processes. This study introduces a novel approach to controlling channel expansion using biomimetic adaptive aggregates, fundamentally overcoming the drawbacks of existing methods relying on intertwined polyelectrolyte chains for channel blockage. Specifically, a pH‐responsive 2D material membrane is constructed through the self‐assembling of protein‐mimetic zwitterionic polydopamine (ZPDA) soft molecular aggregates within graphene oxide (GO) interlayers. Similar to the conformational switch of inserted proteins in cellular membranes, the embedded ZPDA in GO nanofluidic channels undergoes an adaptive conformational transformation in response to pH changes. This dynamic adjustment of ZPDA physicochemical properties allows for reversible regulation of GO nanofluidic channel size and charge by external pH modulation. The resulting GO/ZPDA membrane exhibits programmable separation performance for dye molecules (i.e., water permeance of 18.8–35.4 L m−2 h−1 bar−1 and molecular selectivity of 73.7–32.9) and salt ions (i.e., ionic permeance of 0.69–1.25 mol m−2 h−1 and ionic selectivity of 20.8–21.9). This work sheds new light on the engineering of intelligent stimuli‐responsive 2D nanofluidic channels with adaptive gating properties, holding promise across a wide range of applications including separation, drug delivery, sensing, and catalysis. [ABSTRACT FROM AUTHOR]

Zinc ion batteries (ZIBs) have recently attracted tremendous interest for being low‐cost, environmentally benign, and high energy density. However, the large‐scale practical application of ZIBs is hampered by well‐known undesirable dendrite growth and serious side reactions of the Zn anode during the long‐term cycling process. Herein, a multifunctional water‐glass artificial protection layer with enormous Si─O functional groups is constructed on Zn anode through a simple spin‐coating method. The theoretical and experimental investigation suggests that the as‐constructed interface with rich Si─O hydrophilic functional groups on Zn anode could facilitate the even distribution of electric field distribution and homogeneous wettability, navigate uniform zinc deposition/stripping along the (002) plane, and subsequently lead to well‐suppressed dendrite growth and effective prohibition of oxygen‐involved corrosion. Consequently, the water glass‐modified anode achieves highly reversible Zn plating/stripping over 1500 h at a high current density of 10 mA cm−2 in symmetrical cells, and a high capacity retention ratio of 79.4% at the current density of 5 A g−1 in full cells paired with V2O5 cathode. This proposed water glass coating layer design is cheap, up‐scalable, and facile, which could substantially accelerate the rapid commercialization of zinc anodes and unleash the full potential of renewable ZIBs for next‐generation large‐scale energy storage. [ABSTRACT FROM AUTHOR]

Cocatalyst engineering with non‐noble metal nanomaterials can play a vital role in low‐cost, sustainable, and large‐scale photocatalytic hydrogen production. This research adopts slow carburization and simultaneous hydrocarbon reduction to synthesize carbon‐encapsulated Mo/Mo2C heterostructure nanoparticles, namely Mo/Mo2C@C cocatalyst. Experimental and theoretical investigations indicate that the Mo/Mo2C@C cocatalysts have a nearly ideal hydrogen‐adsorption free energy (ΔGH*), which results in the accelerated HER kinetics. As such, the cocatalysts are immobilized onto organic polymer semiconductor g‐C3N4 and inorganic semiconductor CdS, resulting in Mo/Mo2C@C/g‐C3N4 and Mo/Mo2C@C/CdS catalysts, respectively. In photocatalytic hydrogen evolution application under visible light, the Mo/Mo2C@C with g‐C3N4 and CdS can form the Schottky junctions via appropriate band alignment, greatly suppressing the recombination of photoinduced electron‐hole pairs. The surface carbon layer as the conducting scaffolds and Mo metal facilitates electron transfer and electron‐hole separation, favoring structural stability and offering more reaction sites and interfaces as electron mediators. As a result, these catalysts exhibit high H2 production rates of 2.7 mmol h−1 g−1 in basic solution and 98.2 mmol h−1 g−1 in acidic solution, respectively, which is significantly higher than that of the bench‐mark Pt‐containing catalyst. The proposed cocatalyst engineering approach is promising in developing efficient non‐noble metal cocatalysts for rapid hydrogen production. [ABSTRACT FROM AUTHOR]

Exploring efficient electrocatalysts for oxygen evolution reaction (OER) is an urgent need to advance the development of sustainable energy conversion. Though defect engineering is considered an effective strategy to regulate catalyst activity for enhanced OER performance, the controllable synthesis of defective oxides electrocatalysts remains challenging. Here, oxygen defects are introduced into NiCo2O4 nanorods by an electrochemical lithiation strategy. By tuning in situ lithiation potentials, the concentration of oxygen defects and the corresponding catalytic activity can be feasibly regulated. In addition, the relationship between the changes in the defect density and electronic structure and the lithiation cut‐off voltages is revealed. The results show that NiCo2O4 nanorods undertook intercalation and two‐step conversion reaction, in which the lithiation‐induced conversion reaction gives rise to a CoO@NiO‐based structure with higher defect density and lower oxidation states. As a result, the defective CoO@NiO‐based catalyst exhibits exceptional OER activity with an overpotential of 270 mV at 10 mA cm−2, which is about 74 mV below the pristine nanomaterials. This research proposes a novel strategy to explore high‐performance catalysts with structural stability and defect control. [ABSTRACT FROM AUTHOR]

Excellent bifunctional oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) activity and rapid mass transport capability are two important parameters of electrocatalysts for high‐performance rechargeable Zn–air batteries (ZABs). Herein, an efficient atomic modulation and structure design to promote bifunctional activity and mass transport kinetics of an ORR/OER electrocatalyst are reported. Specifically, atomic Fe−N4 moieties are immobilized on premade hollow carbon fibers with encapsulated Ni nanoparticles (Fe‐N@Ni‐HCFs). Synchrotron X‐ray absorption spectroscopy and spherical aberration‐corrected electron microscope analyses confirm the atomic distribution of the active sites and unique lung bubble‐like hollow architecture of the catalyst, while theoretical investigations reveal that the encapsulated Ni nanoparticles can induce electron distribution of the atomic Fe−N4 moieties to reduce reaction energy barriers. As a result, the prepared catalyst possesses enhanced bifunctional ORR/OER activity and well‐constructed gas–solid–liquid interfaces for improved mass transfer. These synergetic advantages endow the binder‐free Fe‐N@Ni‐HCFs electrode with the remarkable power density and cycling stability for ZABs, outperforming the commercial Pt/C+Ir/C benchmark. This exceptional performance suggests that the proposed strategy can be extended to the design and fabrication of electrocatalysts for energy conversion and storage. [ABSTRACT FROM AUTHOR]

Electrochromic materials can tune the illumination and heat exchange of a building with the environment and thereby save energy in lighting, heating, and air conditioning in a cost‐effective way, which is vital in realizing carbon neutrality. 2D frameworks such as coordination nanosheets (CONASHs) that are widely explored for a wide range of applications in energy storage and conversion can be a cluster of novel electrochromic materials. In this work, a series of transition metal benzenehexathiol (TM‐BHT) CONASHs are theoretically investigated via first‐principles simulations. During ion intercalation and deintercalation in TM‐BHTs, changes in lattice structures, lithium diffusion barriers, atomic charges, bond strength, and electronic properties are explored in‐depth. The incurred changes are then correlated with critical electrochromic properties, including the transmittance adjustment ranges in the visible light, near‐infrared, solar spectrum, and mid‐infrared. Among the various TM‐BHT systems, Cu‐BHT and Ag‐BHT are the most promising broadband electrochromic materials for optical and thermal management in the wavelength range from visible to mid‐infrared. The theoretical guidance from this work paves a new path toward electrochromic applications of CONASHs that exploit the versatility of these 2D materials. [ABSTRACT FROM AUTHOR]

Improving the stability of lithium (Li) anodes is critical for the safety and reliability of Li metal batteries. Developing a 3D conductive Li host is suggested as one of the most promising strategies in this context, especially for suppressing the pulverization of the electrode. However, the material consistency and volume expansion of the electrodes (<15%) represent significant challenges for their applications in commercial pouch cells. In this work, dual‐gradient architecture, combining rigidity and flexibility through the synergistic effect of silver wires and carbon nanotubes, is fabricated by a facile suction filtration method. This unique network shows a volume expansion of only 5.4%, outperforming all previously reported composite Li anodes. In addition, the online digital holography clearly monitors the preferential deposition of metallic Li at the lithiophilic layer. Consequently, the present gradient host effectively prevents the deposition of metallic Li at the electrode/separator interface, resulting in excellent cycling stability in both symmetric and full cells. [ABSTRACT FROM AUTHOR]

Sustainable and highly efficient non‐noble metal catalysts could facilitate the realization of closed‐loop and carbon‐neutral hydrogen (H2) economy via low‐cost electrocatalytic (EC) or photocatalytic (PC) H2 evolution reaction (HER) from water. Herein, molybdenum carbide (MoC) quantum dots onto N‐doped porous carbon are in situ synthesized and immobilized, resulting in a bifunctional catalyst MoC@NC. Density functional theory calculation suggests that the targeted catalyst has a suitable Gibbs free‐energy (ΔGH*) for the adsorption of atomic hydrogen, which is beneficial to both EC and PC HERs. For EC HER, the as‐prepared MoC@NC catalyst delivers a low overpotential of 160 mV at −10 mA cm−2 and a remarkable H2 evolution rate in alkaline electrolytes. For PC HER, MoC@NC couple with 2D graphitic carbon nitride (g‐C3N4), which significantly reduces the PC HER energy barrier and enhances the separation efficiency of photogenerated carriers, and consequently, achieves an outstanding photocatalytic H2 evolution rate of 1709 µmol h−1 g−1, which is 213‐fold of that of pure g‐C3N4. This study paves a new avenue for developing sustainable non‐noble metal catalysts for both EC and PC HERs. [ABSTRACT FROM AUTHOR]

Efficient oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) processes highly rely on the rational design and synthesis of high‐performance electrocatalysts. Herein, comprehensive characterizations and density functional theory (DFT) calculations are combined to verify the important roles of the crystallinity and oxygen vacancy levels of Co(II) oxide (CoO) on ORR and OER activities. A facile and controllable vacuum‐calcination strategy is utilized to convert Co(OH)2 into oxygen‐defective amorphous‐crystalline CoO (namely ODAC‐CoO) nanosheets. With the carefully controlled crystallinity and oxygen vacancy levels, the optimal ODAC‐CoO sample exhibits dramatically enhanced ORR and OER electrocatalytic activities compared with the pure crystalline CoO counterpart. The assembled liquid and quasi‐solid‐state Zn–air batteries with ODAC‐CoO as cathode material achieve remarkable specific capacity, power density, and excellent cycling stability, outperforming the benchmark Pt/C+IrO2 catalysts. This study theoretically proposes and experimentally demonstrates that the simultaneous introduction of amorphous structures and oxygen vacancies could be an effective avenue towards high‐performance electrocatalytic ORR and OER. [ABSTRACT FROM AUTHOR]

The availability of robust, versatile, and efficient photocatalysts is the main bottleneck in practical applications of photocatalytic degradation of organic pollutants. Herein, N‐WO3/Ce2S3 nanotube bundles (NBs) are synthesized and successfully immobilized on a carbon textile, resulting in a flexible and conducting photocatalyst. Due to the large interfacial area between N‐WO3 and Ce2S3, the interwoven 3D carbon architecture and, more importantly, the establishment of a heterojunction between N‐WO3 and Ce2S3, the resultant photocatalyst exhibits excellent light absorption capacity and superior ability to separate photoinduced electron–hole pairs for the photocatalytic degradation of organic compounds in air and water media. Theoretical calculations confirm that the strong electronic interaction between N‐WO3 and Ce2S3 can be beneficial to the enhancement of the charge carrier transfer dynamics of the as‐prepared photocatalyst. This work provides a new protocol for constructing efficient flexible photocatalysts for application in environmental remediation. [ABSTRACT FROM AUTHOR]

Graphene‐based materials have been widely studied to overcome the hurdles of Li–S batteries, but suffer from low adsorptivity to polar polysulfide species, slow mass transport of Li+ ions, and severe irreversible agglomeration. Herein, via a one‐step scalable calcination process, a holey Fe, N codoped graphene (HFeNG) is successfully synthesized to address these problems. Diverging by the holey structures, the Fe atoms are anchored by four N atoms (Fe–N4 moiety) or two N atoms (Fe–N2 moiety) localized on the graphene sheets and edge of holes, respectively, which is confirmed by X‐ray absorption spectroscopy and density functional theory calculations. The unique holey structures not only promote the mass transport of lithium ions, but also prohibit the transportation of polysulfides across these additional channels via strong adsorption forces of Fe–N2 moiety at the edges. The as‐obtained HFeNG delivers a high rate capacity of 810 mAh g−1 at 5 C and a stable cycling performance with the capacity decay of 0.083% per cycle at 0.5 C. The concept of holey structure and introduction of polar moieties could be extended to other carbon and 2D nanostructures for energy storage and conversion devices such as supercapacitors, alkali‐ion batteries, metal–air batteries, and metal–halogen batteries. A holey Fe, N codoped graphene (HFeNG) is developed via a scalable fabrication process that can "dig" holes onto the graphene and "modify" the edge of the holes with the Fe–N2 moiety. The HFeNG could not only accelerate Li+ transportation but also prohibit the transportation of polysulfides and therefore deliver high rate capacities and a stable cycling performance. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride nanosheet (i.e., g‐C3N4) is identified as a suitable graphene analogue due to its high theoretical capacity, wider and vacant structure, and easy synthesis method. Currently, g‐C3N4 nanosheet has limited application in lithium‐ion batteries (LIBs) which is mainly due to the lack of effective intercalation/deintercalation reaction sites, the high binding energy of the Li to the nanosheet, and insufficient conductivity and stability. Density functional theory calculation predicts that the edges of g‐C3N4 fibre have a suitable adsorption energy and bestow a balanced adsorption force and desorption freedom to Li. In order to verify this prediction, g‐C3N4 nanofibre is synthesized with the edges and pores, as well as higher pyridinic nitrogen content, using a simple polymerization/polycondensation method. The as‐prepared g‐C3N4 fibre delivers a remarkable specific capacity of 181.7 mAh g−1, as well as extraordinary stability and power density. At a high rate of 10C, the g‐C3N4 fibre still has a specific capacity of 138.6 mAh g−1 even after 5000 cycles, being the best‐performing g‐C3N4 electrode so far in literature. This work is exemplary in combining theoretical computing and experimental techniques in designing the next generation of electroactive materials for LIBs. A g‐C3N4 fibre structure with edges and low graphitic nitrogen content is developed as an anode material for lithium‐ion batteries. The g‐C3N4 fibre structure delivered an ultrahigh specific capacity of 181.7 mAh g−1 after 200 cycles at 0.5 C and 138.6 mAh g−1 at 10C with an exceptional long life of 5000 cycles. [ABSTRACT FROM AUTHOR]