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A facile yet robust strategy was developed for accelerating the proton transfer of metal hydroxides via incorporating Lewis basic sites, thereby achieving sustainable water oxidation towards practical applications.

A copolymer electrolyte containing 1,3-dioxolane and 1,3,5-trioxane units was synthesized through in situ polymerization and exhibits high ionic conductivity, a high lithium-ion transference number and stable cycling performance.

Electrochemical nitrate reduction reaction (NO3−RR) is an ideal route to produce ammonia (NH3) under ambient conditions. Although a markedly improved NH3 production rate has been achieved on the NO...

The practical application of Lithium-sulfur (Li-S) batteries is significantly inhibited by (i) the notable ‘shuttle effect’ of lithium polysulfides (LiPS), (ii) the corrosion of the lithium interface, and (iii) the sluggish redox reaction kinetics. The functional separator in the Li-S battery has the potential to provide the perfect solution to these problems. Herein a triple-layer multifunctional PVDF-based nanofiber separator, which contains GoTiN/PVDF layer on the top and bottom and ZnTPP/PVDF layer on the middle, is designed. The polarity and porous structure of this multifunctional separator can greatly improve the wettability of electrolytes and enhance the transportation of Li+. With the zinc-based porphyrin framework (ZnTPP) structure, this separator has a strong chemisorption and LiPS conversion ability, which greatly prevent the ‘shuttle effect’. Consequently, the designed multilayer separator showed excellent electrochemical performance. As a result, the cell with GoTiN@ZnTPP@GoTiN nanofiber membrane displayed an initial discharge capacity of 1180 mAh/g with a benign capacity retention of 65.9% at 0.5 C and high coulombic efficiency of more than 98.5% after 100 cycles. Even at 2 C, it can still release a capacity of 798 mAh/g. Moreover, the remarkable capacity of 591 mAh/g could be achieved with a high sulfur load of 5.76 mg/cm2 under a current density of 0.1 C. Based on these merits, this novel and scalable multifunctional separator is a promising candidate to replace the conventional PP separator for advanced Li-S batteries to deal with various challenges.

Carbon nitride materials have achieved great accomplishments in solar-to-hydrogen energy conversion under visible light.

The zinc–air battery with FeS2/NiS2 HDSNRs prepared by a one-step hydrothermal self-template process and high-temperature sulfurization process exhibits long-term stability for 480 h, and was well observed by in situ XRD.

Hierarchically porous N-doped carbon nanofibers anchored with low-loaded FeCo sites (FeCo@PCNFs) were fabricated via the facile electrospinning method followed by carbonization, showing excellent performance for the ORR and primary zinc–air battery.

A simple and effective plasma-activated strategy is employed to synthesize a MOF-based single-atom copper catalyst, which contains abundant low-coordinated copper sites for high-performance CO2 electroreduction to CH4.

Metal phosphides have shown great application potential as anode for sodium-ion batteries (NIBs) owing to high theoretical capacity, suitable operation voltage and abundant resource. Unfortunately, the application of NiP2 anode is severely impeded by low practical capacity and fast capacity decay due to the huge volume variation and low reactivity of internal phosphorus (P) component towards Na+. Herein, electronic structure modulation of NiP2 via heteroatoms doping and introducing vacancies defects to enhance Na+ adsorption sites and diffusion kinetics is successfully attempted. The as-synthesized three-dimensional (3D) bicontinuous carbon matrix decorated with well-dispersed fluorine (F)-doped NiP2 nanoparticles (F-NiP2@carbon nanosheets) delivers a high reversible capacity (585 mAh·g-1 at 0.1 A·g-1) and excellent long cycling stability (244 mAh·g-1 over 1,000 cycles at 2 A·g-1) when tested as anode in NIBs. Density functional theory (DFT) calculations reveal that F doping in NiP2 induces the formation of P vacancies with increased Na+ adsorption energy and accelerates the alloying of internal P component. The F-NiP2@carbon nanosheets//Na3V2(PO4)3 full cell is evaluated showing stable long cycling life. The heteroatoms dopinginduced dual defects strategy opens up a new way of metal phosphides for sodium storage.

Single-atom catalysts based on metal-N

Biological systems employ non-equilibrium self-assembly to create ordered nanoarchitectures with sophisticated functions. However, it is challenging to construct artificial non-equilibrium nanoassemblies due to lack of control over assembly dynamics and kinetics. Herein, we design a series of linear polymers with different side groups for further coordination-driven self-assembly based on shape-complementarity. Such a design introduces a main-chain confinement which effectively slows down the assembly process of side groups, thus allowing us to monitor the real-time evolution of lychee-like nanostructures. The function related to the non-equilibrium nature is further explored by performing photothermal conversion study. The ability to observe and capture non-equilibrium states in this supramolecular system will enhance our understanding of the thermodynamic and kinetic features as well as functions of living systems.

Hypothesis Relative to the bulk systems, the near-wall ( Experiments The combination of active microrheometry (multipole magnetic tweezers) and total internal reflection microscopy (TIRM) was employed to probe the structure–rheology relationships of microgel dispersions near a substrate surface. The ω, T, and ϕeff-dependences of the storage modulus (G′), loss modulus (G"), and softness (J) were analyzed by power-law and Arrhenius-like scaling theories. The fluctuation of J was further analyzed to give a quantitative description of the inhomogeneity in the near-wall regions. Findings (1) Remarkable differences in the rheological behaviors between the bulk and near-wall cases are revealed, where the latter shows a segmented overlap behavior in ϕeff; (2) Five regimes of ϕeff that correspond to distinct physical states of the microgel dispersions are determined; (3) The near-wall local structures exhibit more heterogeneity in the glass and colloidal gel regimes as compared to the liquid regime.

Single-atom catalysts (SACs), as a novel emerging category in heterogeneous catalysis, have exhibited superb activity and selectivity within the scope of many catalytic reactions, originating from their nature of atomic dispersion. However, they are not appropriate for more complicated reactions that benefit from multi-metal promotion, such as the carbon dioxide reduction reaction (CO2 RR). Atomic pair catalysts can provide a synergistic effect to break the intrinsic activity limit. Herein, inspired by theoretical prediction, a hetero-paired atomic-site catalyst (Ni/Fe-N/O-C) was developed for CO2 RR. Typically, the trace-amount-loaded double-atom-site catalysts exhibited outstanding turnover frequencies (≈460 s-1 ) surpassing reported ones by far. Interestingly, the loaded metal contents of the three M-N/O-C samples were extremely low, and Ni/Fe-N/O-C exhibited greatly improved durability compared with pure Ni-N/O-C or Fe-N/O-C and excellent CO selectivity above 80 % within a broad potential window of -1.4 to -1.7 V (vs. saturated calomel electrode, 99.8 % at -1.5 V). The superb performance of diatomic-site catalysts was attributed to the adjusted local environment and electron structure of the active center, which could decrease the reaction barrier of *COOH formation. This work presents new insights into manipulating electrocatalytic performance for the development of more sophisticated active sites.

In this work, the oxidation state of Sn and Cu active sites for CO

Electrochemical reduction reaction is an important approach to utilize CO2 and convert it into valuable products. Exceptional reaction kinetics at a high temperature of solid oxide electrolysis cells (SOECs) attracts particular attention. In this work, we propose to investigate CO2-RR kinetics using a new theoretical method based on the electrical conductivity relaxation (ECR) technique on a typical mixed-conducting Sr2Fe1.5Mo0.5O6-δ (SFM) electrode. Three kinetic parameters that are commonly adopted in the typical electrochemical test experiments consisting of overpotential, current density and area-specific resistance (ASR) are derived. The overpotential resulted from the difference in the oxygen partial pressure is caused by the change of CO2 partial pressure, while current density from the surface reaction rate constant. Accordingly, area-specific resistance, as well as overpotential-current density relationship, can be derived. We believe that this work brings a new method to study the kinetic process of CO2 electrolysis and to evaluate the electrocatalyst activity of developed new electrode materials as well as to benefit the designing of novel electrode electrocatalysts for highly efficient solid oxide electrolysis cells.

The demand for efficient and environmentally-benign electrocatalysts that help availably harness the renewable energy resources is growing rapidly. In recent years, increasing insights into the design of water electrolysers, fuel cells, and metal–air batteries emerge in response to the need for developing sustainable energy carriers, in which the oxygen evolution reaction and the oxygen reduction reaction play key roles. However, both reactions suffer from sluggish kinetics that restricts the reactivity. Therefore, it is vital to probe into the structure of the catalysts to exploit high-performance bifunctional oxygen electrocatalysts. Spinel-type catalysts are a class of materials with advantages of versatility, low toxicity, low expense, high abundance, flexible ion arrangement, and multivalence structure. In this review, we afford a basic overview of spinel-type materials and then introduce the relevant theoretical principles for electrocatalytic activity, following that we shed light on the structure–property relationship strategies for spinel-type catalysts including electronic structure, microstructure, phase and composition regulation, and coupling with electrically conductive supports. We elaborate the relationship between structure and property, in order to provide some insights into the design of spinel-type bifunctional oxygen electrocatalysts.

A well-designed Co–Mo–P active site allows electron transport between Co and MoP, which will reduce the absorption free energy of the intermediates and improve the electrocatalytic activity of the hybrid.

Lithium metal batteries (LMBs) have attracted extensive attention for their ultrahigh energy density. However, the uncontrollable growth of Li-dendrites results in poor cyclability and potential safety risks, thus preventing their practical application. Herein, a flexible and cost-effective aqueous polyethylene oxide (PEO)-based solid-state electrolyte is prepared, which enables uniform and dendrite-free Li deposition by introducing Cs+ with an electrostatic shielding mechanism at high current densities. The self-assembly of PEO and bacterial cellulose by hydrogen bonding reduces the crystallinity of PEO and increases uniformly the distribution of lithium ions. With excellent flexibility and thermal stability, such a 3D polymer solid-state electrolyte exhibits an enhanced electrochemical stability window of 5.8 V versus Li/Li+ potential and a high ionic conductivity of 1.28 × 10−4 S cm−1 at 60 °C. The Li|BC-PEO-Cs+|Li symmetric cells operate stably for more than 1000 h. Furthermore, Li|BC-PEO-Cs+|LiFePO4 (LFP) cells show remarkable enhancement in capacity (163.4 mA h g−1 at 0.1 C), cycling stability (with a capacity retention of 96% after 500 cycles at 1 C) and high functionality and safety (withstanding folding and cutting) in practical applications.

The rational design and construction of the efficient and robust non-noble metal bifunctional oxygen electrocatalysts is of critical significance due to the attention given to reversible metal–air batteries. In this paper, we report novel two-dimensional “senbei”-like Co9S8/CeO2/Co-NC nitrogen-doped carbon nanosheets (Co9S8/CeO2/Co-NC) derived from a unique 2D Co/Ce bimetallic ZIF. The phase transition from 3D spherical Co-ZIF to 2D Co/Ce-ZIF was achieved through the introduction of Ce ions. Profiting from the successful construction of the unique Co9S8/CeO2 heterostructure and the synergetic effect of two components, the as-prepared Co9S8/CeO2/Co-NC exhibited excellent electro-performance in both the oxygen evolution reaction (Ej=10 = 1.60 V) and oxygen reduction reaction (E1/2 = 0.875 V). Furthermore, when used as a bifunctional air electrode for Zn-air batteries, Co9S8/CeO2/Co-NC reached a high peak power density of ≈164.24 mW cm−2 at a high current density of ≈351 mA cm−2 and displayed an outstanding cycling stability of more than 668 h at 5 mA cm−2. This research provides new guidelines for preparing hybrid materials from cobalt-based sulfide species and CeO2 for electrocatalysis and energy storage or other fields.