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Low‐cost, high‐voltage‐platform, and high‐capacity MnO2 is the most promising cathode candidate for developing high‐energy‐density aqueous zinc‐ion batteries. However, the Buckets effect of runaway phase transition and irreversible dissolution restricts the electrochemical performance of MnO2. To address this issue, this report presents a bottom‐up targeted assembly concept driven by Gibbs free energy for the design of a robust Ni‐MnO2‐xFx host via Ni2+ pre‐intercalation coupled with fluorine doping. The Gibbs free energy of the host is regulated by the coordination of interlayer reinforcement and interfacial defect repair, which prevents the “layer‐to‐spinel” transition and inhibits dissolution during long‐term cycling. As expected, this cathode provides superior H+/Zn2+ storage performance across a wide temperature range. A capacity of 180.4 mAh g−1 is retained after 1000 cycles at 2 A g−1, a high specific capacity of 293.9 mAh g−1 is retained after 250 cycles at 50 °C and 2 A g−1, and a capacity of 144.5 mAh g−1 is retained after 3000 cycles at 0 °C and 0.5 A g−1. This work provides new insights into the design of stable aqueous battery‐compatible hosts for aqueous zinc‐ion batteries as well as other battery chemistries. [ABSTRACT FROM AUTHOR]

Designing effective electrocatalysts tailored for targeted reactions requires fundamental insights into the structure dependence of the reaction microenvironment. Herein, inspired by finite element simulations, N,O co‐doped carbon nanosheets featuring a hierarchical micro/mesoporous structure to form an oxygen‐rich and local alkaline‐like microenvironment for the two‐electron oxygen reduction reaction (2e− ORR) in a neutral medium are designed. The in situ and ex situ test results confirmed that the micro/mesoporous carbon architecture can elevate the local pH and accelerate the generation of intermediates (*O2, *OOH), leading to high‐efficiency H2O2 production. Utilizing this favorable microenvironment, N,O‐CNS0.5 demonstrated exceptional H2O2 electrosynthesis performance in neutral media, achieving a superior H2O2 yield rate (6705 mmol gcatalyst−1 h−1 in a flow cell). Additionally, comparative experiments and density‐functional theory calculations provided confirmation of the bi‐doping of N and O as the active origin responsible for the electrochemical 2e− ORR. This study synergistically manipulates the reaction microenvironment and active sites, providing an opportunity for efficient H2O2 electro‐production in a neutral medium. [ABSTRACT FROM AUTHOR]

Photocatalytic and electrocatalytic N2 reduction reactions (N2RR) for NH3 synthesis from abundant N2, H2O, solar energy, and renewable electricity is very attractive. 2D catalysts, including photocatalysts (TiO2, Bismuth‐based materials, layered double hydroxides (LDHs), carbon nitride, Fe@Graphene, MoS2 et al.) and electrocatalysts (metal, graphene, carbon, boron nitride (BN), boron carbide (B4C), black phosphorus (BP), boron, transition‐metal oxide/sulfide/nitride/phosphide), have emerged as promising candidates for N2RR due to their unique physical, chemical and electronic properties. Compared with their bulk counterparts, 2D catalysts usually possess the shortened carrier diffusion pathways, higher specific surface areas and conductivity, more vacancy‐type defects as well as exposed edge sites, which is beneficial to the separation of photogenerated carriers, and the adsorption and activation of N2 molecules. This review highlights the recent progress and developments in 2D catalysts for photocatalytic and electrocatalytic N2RR for the first time. First, the prospects for photocatalytic and electrocatalytic N2RR for NH3 synthesis, and the advantages of 2D catalysts are briefly introduced. Second, the application of 2D catalysts for N2 photoreduction and electroreduction is systematically summarized. Finally, the major challenges and future outlook of this burgeoning area are provided. [ABSTRACT FROM AUTHOR]

Rechargeable Zn‐ion batteries (ZIBs), prospective candidates for broad‐scale energy storage, still encounter many challenges such as hydrogen evolution corrosion, Zn dendrite growth, and capacity fading. Therefore, one specific strategy for tuning the internal structure of solid polymer electrolytes (SPEs) via organic additives is proposed to address these urgent bottlenecks simultaneously. With trimethyl phosphate (TMP) addition, the coordination environment of Zn2+ in SPEs is altered and exists as Zn2+(TMP)x(OTf−)y coordinated molecules. Meanwhile, the strong interaction between TMP and Zn enables the preferential growth of Zn(002) planes during electrodeposition, which is proved based on first‐principles calculations, finite element simulations, and multiple in situ characterizations. Such excellent interfacial engineering in situ forms the solid electrolyte interface rich in Zn3(PO4)2 fast ion conductor and guarantees one ultra‐long cycle life for more than 6000 h in a Zn|Zn symmetric cell at 0.1 mA cm−2. Moreover, the universality of TMP‐modified SPEs shows 1000 times stable cycling of VO2(B)|Zn full cells at 1 A g−1 under 0 °C with 95.24% capacity retention, which satisfies potential applications of wide‐ranging energy storage based on solid‐state ZIBs. [ABSTRACT FROM AUTHOR]

The undesirable side reactions and uncontrolled deposition leads to the electrochemical failure of Zn metal anodes. Herein, driven by theory calculations, a surface texture engineering and passivation layer protection dual‐interface strategy is developed. Benefiting from the complementary interface effect, such a dual‐interface can realize the integrated regulation of interfacial transport and deposition. That is, inhibiting water‐induced side reactions, accelerating the de‐solvation of hydrated zinc ions, homogenizing the ion flux, and guiding the Zn(002)‐preferred orientation deposition. As a result, such a dual‐interface modulated Zn electrode enables a significantly extended stability and a smaller nucleation barrier and polarization effect. Unexpectedly, it can steadily operate for 6600 h at 0.5 mA cm−2 and 0.5 mA h cm−2, corresponding to a lifespan >9 months. Highly reversible Zn plating and stripping can be still retained when the current density is improved up to 1, 5, 10, and even 20 mA cm−2. Beyond that, when it is applied to Zn metal batteries, enhanced rate capability, and cyclic stability can be realized in both aqueous Zn/MnO2 batteries and solid‐state Zn/VO2 batteries. This design concept of complementary interface effect is expected to provide a new insight into high reversibility Zn metal anodes. [ABSTRACT FROM AUTHOR]

The rational design and development of highly efficient oxygen evolution reaction (OER) electrocatalysts is vital for the application of renewable energy devices. Recently, the strategy of defect engineering draws much attention due to its positive effect on regulating the electronic structure, and thus, promoting the electrocatalytic performance of various materials. In this review, the main focus is on the cation vacancy defects of transition metal‐based electrocatalysts; the latest progress in cation vacancy defect engineering for the electrocatalytic OER is summarized. The different effects of cation vacancy defects on OER are well discussed together with the reaction mechanism, mainly including improving the conductivity, optimizing the adsorption of key intermediates, guiding the surface reconstruction to form active species, and enhancing the long‐term stability. Then, methods to construct cation vacancy defects on different electrocatalysts and the characterization of cation vacancies are systematically introduced. Finally, the remaining challenges and future prospects of cation vacancy defect engineering for promoting OER performance are further proposed. [ABSTRACT FROM AUTHOR]

The electrochemical nitrate reduction reaction (NO3−RR) provides a promising route to produce ammonia (NH3) while addressing environmental issues of NO3−. Although great success has been achieved on the development of efficient NO3−RR electrocatalysts, few has concerned about how to capture NH3 from the electrolyte, despite that the production and capture of NH3 are equally important to the practical application of NO3−RR. Here, inspired by the fact that nearly all in situ generated NH3 is gaseous at the electrode surface during the small‐current NO3−RR, a "two‐in‐one" flow cell electrolyzer is smartly designed that integrates the chambers of NO3−RR electrolysis and NH3 capture through a commercial gas diffusion electrode, aiming at achieving the synchronization of NH3 production and capture. Remarkably, this electrolyzer also enables rapid transport of NH3 products away from the three‐phase reaction interfaces, thereby significantly promoting the conversion of NO3− to NH3. By using robust electrocatalysts with the function like nanoreactors, the electrolyzer delivers a maximum ammonia Faradaic efficiency of 90.2%, along with a large current density (−528.0 mA cm−2) and NH3 capture rate of 90.4%. Clearly, this work provides opportunities to concurrently produce and capture NH3 and thus help the realization of nitrogen cycle. [ABSTRACT FROM AUTHOR]

Exploring advanced technologies to efficiently produce green hydrogen energy is imperative to alleviate the energy crisis and environmental pollution. Conventional overall water electrolysis (OWE) has been regarded as a promising approach for effective H2 production, however, it is largely restricted by the sluggish kinetics of the anodic oxygen evolution reaction (OER). Coupling kinetically favorable anodic reactions, such as biomass‐derived compound oxidation and pollutant degradation, with the hydrogen evolution reaction (HER) in hybrid water electrolysis (HWE), can not only solve the biomass recycling and pollutant emission problems but also save the energy cost for clean H2 generation. Hence, various advanced earth‐abundant electrocatalysts have been developed to catalyze those promising anodic reactions, yet some problems such as tedious preparation and unsatisfactory performance still exist. Given the gap between research and practical applications, this review summarizes the recent progress in electrocatalysts for diverse alternative anodic oxidation reactions over the last five years together with their application in HWE systems. An in‐depth understanding of different reaction mechanisms and assessments toward electrocatalysts is discussed to further enhance anodic efficiency. The advantages, differences, and critical issues of different HWE systems are thoroughly discussed as well, providing a new avenue for low‐voltage H2 production from renewable resources and waste products. [ABSTRACT FROM AUTHOR]

The electronic band structure of MoS2 exerts far‐ranging effects on the applications of these materials, ranging from chemical catalysis, electronic, and magnetic behaviors. However, the underlying relationship between the electronic band structure and activity is largely unknown in heterogeneous catalysis including the hydrogen evolution reaction, partly due to the lack of a controllable methodology to achieve desirable electronic band structures in the 2H‐phase MoS2. Herein it is demonstrated that dual dopants can engineer the band structure of MoS2 by substituting into the adjacent Mo sites. Specifically, these constructed PdRe dimers bridged by sulfur (PdSRe sites) introduce conducting electronic states around the Fermi level to increase the metallic characteristics of MoS2, resulting in metallic‐like behavior, which is initially semiconducting. Furthermore, the efficacy of inducing a phase conversion from 2H to metallic 1T is higher for codoping with dual dopants as compared to that for the use of a single dopant, thereby generating more intrinsically active PdS*Mo sites to further increase active sites density. Ultimately, this leads to the MoS2 catalyst showing a low overpotential of 46 mV at a current density of 10 mA cm−2 and a high exchange current density of 1.524 mA cm−2, along with superior operating durability. [ABSTRACT FROM AUTHOR]

Keywords: 2D catalysts; electrocatalysis; N2 reduction reaction; NH3; photocatalysis EN 2D catalysts electrocatalysis N2 reduction reaction NH3 photocatalysis 1 1 1 03/22/21 20210318 NES 210318 The Cowherd and Weaving Maid is a famous folk love story in ancient China. 2D Electrocatalysts: Recent Progress in 2D Catalysts for Photocatalytic and Electrocatalytic Artificial Nitrogen Reduction to Ammonia (Adv. 2D catalysts, electrocatalysis, N2 reduction reaction, NH3, photocatalysis. [Extracted from the article]

Rechargeable aqueous zinc‐ion batteries (AZIBs) have attracted extensive attention and are considered to be promising energy storage devices, owing to their low cost, eco‐friendliness, and high security. However, insufficient energy density has become the bottleneck for practical applications, which is greatly influenced by their cathodes and makes the exploration of high‐performance cathodes still a great challenge. This review underscores the recent advances in the rational design of advanced cathodes for AZIBs. The review starts with a brief summary and evaluation of cathode material systems, as well as the introduction of proposed storage mechanisms. Then, fundamental problems associated with ion and electron transport behaviors inside the electrode will be pointed out and followed by potential solutions, aiming to reveal the correlation between cathode architecture design and efficient transport kinetics through structural engineering. Afterward, the structural engineering for designing advanced cathodes, including interlayer intercalation, doping effects, defect engineering, surface coatings, composite formation, and morphology control, are summarized and discussed from the view of experimental and theoretical results. Finally, the critical research challenges and future perspectives on advanced cathode materials as well as the potential developing directions of AZIBs are also given. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: electronic structures engineering; heterointerfaces; metal borates; nanomeshes; water splitting In article number 1901130, Chuanxin He and co-workers propose a general, one-step strategy for crafting a series of ultrathin metal borate nanomeshes with abundant nanopores by capitalizing on 3D bark-like N-doped carbon as nanoreactors. Electronic structures engineering, heterointerfaces, metal borates, nanomeshes, water splitting.

Ultrathin nanomeshes perfectly inherit the integrated advantages of ultrathin 2D materials and porous nanostructures, which have shown their great application potential in catalysis and electronic devices. Here, the general synthesis of ultrathin metal borate (i.e., Co‐Bi, Ni‐Bi, and Fe‐Bi) nanomeshes is reported by capitalizing on 3D bark‐like N‐doped carbon (denoted BNC) as nanoreactors. Indeed, this strategy is straightforward, only comprising a one‐step reaction between metal cations and sodium borohydride without using templates. As nanoreactors, the BNC derived from biomass waste of lychee exocarp possesses distinctive advantages of low cost, fractured textures, porous nanostructures (surface area: 1915.5 m2 g−1), electronegative surface (zeta potential: −43.4 mV), and superhydrophilicity for greatly facilitating the adsorption of metal cations with strong strength to effectively control the growth of 2D nanomeshes. The as‐synthesized Co‐Bi and Ru‐doped Co‐Bi (Ru‐Co‐Bi) nanomeshes exhibit excellent performance for the oxygen evolution reaction and hydrogen evolution reaction, respectively. Impressively, the water splitting device based on the Co‐Bi and Ru‐Co‐Bi nanomeshes can enable a current density of 10 mA cm−2 at a small cell voltage of 1.53 V. Therefore, this work paves new avenues for the facile synthesis of ultrathin metal nanomeshes. [ABSTRACT FROM AUTHOR]

In article number 1803867 by Chuanxin He and co‐workers an easy yet robust route is developed to craft N, O‐codoped graphene‐integrated boxes by employing hybrids containing polymers and Prussian blue analogue cubes as precursors. Benefiting from the hierarchically porous nanostructures and highly active N, O‐codoped graphene, the resulting electrocatalysts display excellent performance in overall water splitting and Zn–air batteries. [ABSTRACT FROM AUTHOR]

Despite the exciting achievements made in synthesis of monofunctional electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), or hydrogen evolution reaction (HER), it is challenging to develop trifunctional electrocatalysts for both ORR/OER/HER. Herein, N, O‐codoped graphene nanorings‐integrated boxes (denoted NOGB) are crafted via high‐temperature pyrolysis and following acid etching of hybrid precursors containing polymers and Prussian blue analogue cubes. The electrochemical results signified that the resulting NOGB‐800 (800 refers to pyrolysis temperature) is highly active for trifunctional electrocatalysis of ORR/OER/HER. This can be reasonably attributed to the advanced nanostructures (i.e., the hierarchically porous nanostructures on the hollow nanorings) and unique chemical compositions (i.e., N, O‐codoped graphene). More attractively, the rechargeable Zn–air battery based on NOGB‐800 displays maximum power density of 111.9 mW cm−2 with small charge–discharge potential of 0.72 V and excellent stability of 30 h, comparable with the Pt/C+Ir/C counterpart. The NOGB‐800 could also be utilized as bifunctional electrocatalysts for overall water splitting to yield current density of 10 mA cm−2 at a voltage of 1.65 V, surpassing most reported electrocatalysts. Therefore, the NOGB‐800 is a promising candidate instead of precious metal–based electrocatalysts for the efficient Zn–air battery and water splitting. An easy yet robust route, for the first time, is developed to craft N, O‐codoped graphene‐integrated boxes by employing hybrids containing polymers and Prussian blue analogue cubes as precursors. Benefiting from the hierarchically porous nanostructures and highly active N, O‐codoped graphene, the resulting electrocatalysts display excellent performance on the overall water splitting and Zn–air battery. [ABSTRACT FROM AUTHOR]