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In natural plants, Mn4CaO5 cluster with metal‐oxo "distorted chair"‐like structure exhibits excellent oxygen evolution activity. However, the performance of biomimetic oxygen evolution catalysts based on the Mn4CaO5‐like structure is far inferior to expectations. Herein, Ca and Ni are first doped together into birnessite and constructed a "distorted chair"‐like structure unit Mn4‐xNixCaO5 in a birnessite‐like Ca‐Mn(Ni)‐O catalyst, the biomimetic Mn4‐xNixCaO5 unit efficiently activates lattice oxygen and boosts the O─O coupling in oxygen evolution reaction (OER), which allows the catalyst to perform superior OER activity with an outstanding overpotential of 184 mV at 300 mA cm−2. Besides, the birnessite‐like Ca‐Mn(Ni)‐O catalyst is stabilized by coupling to NiMnO3 nanoplate, thus forming a stable catalyst that can work for >500 h without attenuation. This work optimizes biomimetic structures by introducing new elements, which provides new insight into developing efficient biomimetic materials. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO2 reduction reaction (CO2RR) in acidic media is a promising approach to overcome the unavoidable formation of carbonates in alkaline or neutral electrolytes. However, the proton-rich environment near the catalyst surface favors hydrogen evolution reactions (HER), leading to lower energy efficiency of the desired products, especially in industrial-level current densities. Here, quaternary ammonium cationic surfactant (cetyltrimethylammonium bromide (CTAB)) was introduced into acidic electrolyte to modulate the interfacial microenvironment, which greatly enhanced CO2 electroreduction to formic acid (HCOOH) at the Bi/C nanoparticles electrode. Using a Bi/C nanoparticles electrode with CTAB added, constant production of formic acid was enabled with a cathodic energy efficiency of > 40% and maximum FEHCOOH (FE = Faradaic efficiency) of 86.2% at −400 mA·cm−2 over 24 h. Combined with in-situ attenuated total reflection Fourier transform infrared spectroscopy, the concentration of *OCHO intermediates significantly increased after CTAB modification, confirming that the hydrophobic interface microenvironment formed by dynamic adsorption of positively charged long alkyl chains on Bi/C nanoparticle electrodes inhibited HER and improved the selectivity of CO2RR to HCOOH. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) covalent organic frameworks (COFs) and their derivatives have been widely applied as electrocatalysts owing to their unique nanoscale pore configurations, stable periodic structures, abundant coordination sites and high surface area. This work aims to construct a non-thermodynamically stable Pt-N2 coordination active site by electrochemically modifying platinum (Pt) single atoms into a fully conjugated 2D COF as conductive agent-free and pyrolysis-free electrocatalyst for the hydrogen evolution reaction (HER). In addition to maximizing atomic utilization, single-atom catalysts with definite structures can be used to investigate catalytic mechanisms and structure-activity relationships. In this work, in-situ characterizations and theoretical calculations reveal that a nitrogen-rich graphene analogue COF not only exhibits a favorable metal-support effect for Pt, adjusting the binding energy between Pt sites to H* intermediates by forming unique Pt-N2 instead of the typical Pt-N4 coordination environment, but also enhances electron transport ability and structural stability, showing both conductivity and stability in acidic environments. In addition to maximizing atomic utilization, single-atom catalysts with defined structures can be used to investigate catalytic mechanisms and structure-activity relationships. Here, authors study a non-thermodynamically stable Pt-N2 active site for the electrochemical hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Metal single atoms (SAs) anchored in carbon support via coordinating with N atoms are efficient active sites to oxygen reduction reaction (ORR). However, rational design of single atom catalysts with highly exposed active sites is challenging and urgently desirable. Herein, an anion exchange strategy is presented to fabricate Fe‐N4 moieties anchored in hierarchical carbon nanoplates composed of hollow carbon spheres (Fe‐SA/N‐HCS). With the coordinating O atoms are substituted by N atoms, Fe SAs with Fe‐O4 configuration are transformed into the ones with Fe‐N4 configuration during the thermal activation process. Insights into the evolution of central atoms demonstrate that the SAs with specific coordination environment can be obtained by modulating in situ anion exchange process. The strategy produces a large quantity of electrochemical accessible site and high utilization rate of Fe‐N4. Fe‐SA/N‐HCS shows excellent ORR electrocatalytic performance with half‐wave potential of 0.91 V (vs. RHE) in 0.1 M KOH, and outstanding performance when used in rechargeable aqueous and flexible Zn‐air batteries. The evolution pathway for SAs demonstrated in this work offers a novel strategy to design SACs with various coordination environment and enhanced electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Oxygen vacancies‐enriched black TiO2 is one promising support for enhancing hydrogen evolution reaction (HER). Herein, oxygen vacancies enriched black TiO2 supported sub‐nanometer Pt clusters (Pt/TiO2‐OV) with metal support interactions is designed through solvent‐free microwave and following low‐temperature electroless approach for the first time. High‐temperature and strong reductants are not required and then can avoid the aggregation of decorated Pt species. Experimental and theoretical calculation verify that the created oxygen vacancies and Pt clusters exhibit synergistic effects for optimizing the reaction kinetics. Based on it, Pt/TiO2‐OV presents remarkable electrocatalytic performance with 18 mV to achieve 10 mA cm−2 coupled with small Tafel slope of 12 mV dec−1. This work provides quick synthetic strategy for preparing black titanium dioxide based nanomaterials. [ABSTRACT FROM AUTHOR]

Charge separation and transfer are central issues dominating the underlying energy conversion mechanisms of photosynthetic systems. Here, inspired by nature, a multi‐interfacial engineering strategy for constructing a strongly coupled interactive transmission network for stable and efficient photocatalytic hydrogen production is proposed. A multivariate all‐solid‐state Z‐scheme with intimate electron interactions is formed through strong bridging bonds due to Ti orbit modulation and stacking hybridization between hybrids. The electron couple structure realizes an efficient carrier directional separation and transfer, enabling the charge separation efficiency to be enhanced dramatically by 7.2 times. Furthermore, the resulting material provides a highly stable photocatalytic hydrogen activity, up to 15.29 mmol h−1 g−1, 18.8 times higher than pure carbon nitride, surpassing many reported photocatalysts. This work represents a significant development and helps develop a sound foundation for future design principles in accelerating charge transfer. [ABSTRACT FROM AUTHOR]

A designed structure which CoP nanoparticles (NPs) ingeniously connected with graphene‐like carbon layer via in‐situ generated interfacial oxygen‐bridge chemical bonding was achieved by a mild phosphorization treatment. The results proved that the presence of phosphorus vacancies is a crucial factor enabling formation of Co−O−C bonds. The direct coupling of edge Co of CoP with the oxygen from functional groups on the carbon layer was proposed. As a catalyst for electrocatalytic water splitting, the manufactured Fe2O3@C@CoP core‐shell structure manifested a low overpotential of 230 mV, a low Tafel slope of 55 mV dec−1, and long‐term stability. Density functional theory calculations verified that the Co−O−C bond played a critical role in decreasing the thermodynamic energy barrier of reaction rate‐determining step for the oxygen evolution reaction (OER). This synthetic route might be extended to construct metal−O−C bonds in other transition metal phosphides (or selenides, sulfides)/carbon composites for highly efficient OER catalysts. [ABSTRACT FROM AUTHOR]

To boost the performance for various applications, a rational bottom‐up design on materials is necessary. The defect engineering on nanoparticle at the atomic level can efficiently tune the electronic behavior, which offers great opportunities in enhancing the catalytic performance. In this paper, we optimized the surface oxygen vacancy concentration and created the lattice distortion in rare‐earth‐based perovskite oxide through gradient replacement of the B site with valence alternated element. The dual defects make the electron spin state transit from low spin state to high spin state, thus decreasing the charge transport resistance. Furthermore, assembly the modified nanoparticle subunits into the micro‐sized hollow multishelled structures can provide porous shells, abundant interior space and effective contact, which enables an enhanced mass transfer and a shorter charge transport path. As a result, the systemic design in the electronic and nano‐micro structures for catalyst has brought an excellent oxygen evolution performance. [ABSTRACT FROM AUTHOR]

Atomic metal species‐based catalysts (AMCs) show remarkable possibilities in various catalytic reactions. The coordination configuration of the metal atoms has been widely recognized as the determining factor to the electronic structure and the catalytic activity. However, the synergistic effect between the adjacent layers of the multilayered AMCs is always neglected. We reported an atomic Co and Pt co‐trapped carbon catalyst, which exhibits a ultrahigh activity for HER in the wide range of pH (η10=27 and 50 mV in acidic and alkaline media, respectively) with ultralow metal loadings (1.72 and 0.16 wt % for Co and Pt, respectively), which is much superior to the commercial Pt/C. Theoretical analysis reveals that the atomic metals on the inner graphitic layers significantly alter the electronic structure of the outmost layer, thus tailoring the HER activity. This finding arouses a re‐thinking of the intrinsic activity origins of AMCs and suggests a new avenue in the structure design of AMCs. [ABSTRACT FROM AUTHOR]

Orbital hybridization is a promising approach to modulating the electronic structure of the designed electrocatalysts to boost reaction kinetics. In contrast to d‐d hybridization, p‐d orbital hybridization between p‐block elements and d‐block metals can provide new opportunities to modulate the electronic properties and thus promote the catalytic performance. Herein, a phosphorus‐doped osmium (P‐Os) catalyst is designed through ultrafast (20 s) microwave plasma engineering. Theoretical calculations verify the d‐p orbital hybridization between P and Os, leading to the modulation of the d‐band center of the Os active site. Specifically, P neighboring Os exhibit the highest catalytic activity, facilitating crucial processes such as H2O/H* adsorption and dissociation. The overpotential of P‐Os in alkaline seawater is only 152 mV at 1 A cm−2, which is superior to the reported seawater electrocatalysts. Moreover, the synthesized P‐Os catalysts are integrated into an anion exchange membrane (AEM) electrolyzer, demonstrating remarkable performance. The AEM electrolyzer requires 1.86/2.02 V to achieve 500/1000 mA cm−2 current densities. Then, the achieved P‐Os have great potential for practical electrocatalytic water‐splitting applications. [ABSTRACT FROM AUTHOR]

Highlights from the article: Innenrücktitelbild: Charge Polarization from Atomic Metals on Adjacent Graphitic Layers for Enhancing the Hydrogen Evolution Reaction (Angew. B Ein Kohlenstoff-Hohlkugelkatalysator b mit Co-Pt-Spezies, die in einer mehrlagigen Kohlenstoffhülle eingeschlossen sind, wurde durch elektrochemische Aktivierung synthetisiert. In ihrer Zuschrift auf S. 9504 untersuchen X. Yao et al. den synergistischen Effekt zwischen den atomaren Metallen auf die angrenzenden Kohlenstoffschichten und zeigen, wie die Ladungspolarisation durch die Kohlenstoffschichten hindurch die elektrokatalytische Wasserstoffentwicklung verstärkt.

Stable and effective acidic CO 2 electroreduction: A simple "SiO 2 aerosol electrode modification" strategy for producing formic acid in acidic electrolytes has been proposed, which reduces HER competition and prevents catalyst corrosion, achieving excellent stability and selectivity of CO 2 RR at industrial-level current. [Display omitted] • A strategy for enhancing acidic CO 2 RR by coating hydrophobic SiO 2 aerosol on catalyst layer is developed. • The Sn-C/SiO 2 reaches 90% HCOOH selectivity for CO 2 RR at industrial-level current. • In-situ FTIR spectroscopy indicates that Sn-C/SiO 2 has higher performance due to increased *OCHO coverage. Acidic CO 2 electroreduction has the potential to synthesize low carbon footprint chemicals using renewable electricity. However, proton-rich environments can lead to strong hydrogen evolution reaction (HER) and severe degradation of electrochemical CO 2 reduction reaction (CO 2 RR) performance. Modulating electrode structure plays a critical role in improving the local microenvironment of CO 2 RR electrolytes. Here, by covering the catalyst layer with a hydrophobic silica aerosol layer, the surface of the catalyst is protected from corrosion, thereby increasing the efficiency and stability of the system. In the flow cell, the Sn-C/SiO 2 -3 catalyst has high formic acid (HCOOH) selectivity at high current density (∼90 % at −400 mA cm−2). Importantly, the Sn-C/SiO 2 -3 catalyst can operate stably for 45 h at −400 mA cm−2. Combined in situ infrared analysis reveals that hydrophobic SiO 2 aerosol layer can engineer the local microenvironment over the Sn-C catalyst surface by increasing the coverage of *OCHO to improve the CO 2 RR, which ultimately promotes high-efficiency CO 2 conversion to HCOOH in strong acidic media. This surface coating strategy for adjusting the interface microenvironment can also be used for other electrocatalytic reactions. [ABSTRACT FROM AUTHOR]

Rational control of the compositions, morphologies and sizes of electrocatalyst are the key factors for achieving high performance of electrocatalytic reactions. Herein, a newly ultrathin PtRuRhCoNi high-entropy alloy nanowires (HEA-NWs) (~1.6 nm) catalyst is designed. The PtRuRhCoNi NWs/C achieved high mass activity of 7.68 A mg−1 PtRuRh , ultrahigh C1 selectivity of 78% for ethanol oxidation reaction. For hydrogen evolution reaction, the PtRuRhCoNi NWs/C also reached high mass activity, turnover frequency (11.99 A mg−1 PtRuRh , 31.9 s−1, 0.5 M H 2 SO 4 and 8.07 A mg−1 PtRuRh , 26.7 s−1, 1 M KOH at −0.05 V vs. RHE) and stability. Theoretical calculations demonstrated that the excellent electroactivity of HEA is benefited by the self-complementary effect through strong orbital coupling, which maximized the electroactivity towards both oxidation and reduction and preferred binding of key intermediate. The design of pH-universal multifunctional catalyst by rational control of the compositions, morphologies and sizes strategy can facilitate the research of advanced catalysts. [Display omitted] • A newly ultrathin PtRuRhCoNi high-entropy alloy nanowires (~1.6 nm) catalyst is designed. • The PtRuRhCoNi NWs/C reaches 7.68 A mg−1 PtRuRh activity and 78% C1 selectivity for EOR. • The PtRuRhCoNi NWs/C achieves high mass activity, TOF and stability for HER in acidic and alkaline solutions. • DFT shows that the excellent electroactivity of HEA is benefited by the self-complementary effect through strong orbital coupling. [ABSTRACT FROM AUTHOR]

[Display omitted] • Homogeneous porous CoP nanoparticles are prepared by a facile templating strategy. • The porous CoP nanoparticle composite reveals improved catalytic activity and stability towards OER. • The porous CoP nanoparticle exhibits superior OER activity than commercial RuO 2. • This strategy would be helpful for the development of other materials for electrochemical applications. The realization of hydrogen generation through industrial electrochemical water splitting is largely prohibited by oxygen evolution reaction (OER) owing to its intrinsically sluggish kinetics. Therefore, the development of highly efficient OER electrocatalysts is of great significance. Recently, various composites with porous nanostructures and superior catalytic ability for different electrochemical applications have been fabricated based on zeolitic imidazolate frameworks (ZIFs), and transition metal phosphides (TMPs) have been reported to be one of the most promising electrocatalysts for OER. Herein, in this work, we designed the porous CoP nanoparticles (P-CoP-NPs) composite as an effective catalyst for OER via a facile templating strategy using polystyrene (PS) spheres as the template and ZIF-67 as the cobalt source. The obtained P-CoP-NPs composite largely improved the OER catalytic performance. Such optimized P-CoP-NPs catalyst required an overpotential of 320 mV to achieve the current density of 10 mA cm−2 in alkaline solution. P-CoP-NPs catalyst still exhibited superior catalytic stability after continuous water oxidation process with negligible decay in potential, indicating its potential to be a high-performance OER electrocatalyst. The strategy used in this study makes it possible to design and synthesize low-cost electrocatalysts with earth-abundant elements for water splitting in practical applications. [ABSTRACT FROM AUTHOR]

Exploring a facile and cost-efficient approach to synthesize electrocatalysts that promoting the interconversion between H 2 O and O 2 remains a crucial challenge. In this work, we report a convenient and effective strategy to synthesis Co metal and MnO immobilized on carbon nanotubes (MnO/Co-CNTs) vis strong metal-support interaction (SMSI). The CNTs support anchored abundant MnO/Co nanoparticles (NPs) in a small size of ~2 nm, when the strong interaction between them suppressed the homogeneous nucleation of MnO/Co during high temperature sintering. Thus, enormous well-dispersed catalytic active sites are produced on the conductive CNTs. Together with the boosted charge transfer between MnO/Co and support, the catalytic activity of MnO/Co-CNTs is eventually significantly promoted. The catalyst shows an efficient oxygen reduction reaction (ORR), oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline solution. Furthermore, SMSI alleviate the agglomeration of NPs and secure the active sites during electrochemical reactions, which account for the enhanced catalytic durability for ORR, OER and HER. In consequence, the MnO/Co-CNTs catalyst shows excellent performance for rechargeable Zn-air battery, and can be utilized to catalyze overall water splitting to produce hydrogen and oxygen. This work manifests a promising approach for optimizing the catalytic performance of the NPs. Superior nonprecious MnO/Co-CNTs bifunctional oxygen electrocatalyst was successfully fabricated through strong metal-support interactions. The extremely outstanding catalytic activities of the as-developed MnO/Co-CNTs were ascribed to the enormous well-dispersed catalytic active sites and the boosted charge transfer between MnO/Co and carbon nanotubes support. Impressively, the as-fabricated rechargeable Zn-air battery afforded an extremely high charge/discharge stability. [Display omitted] • MnO/Co-CNTs oxygen electrocatalyst was obtained by strong metal-support interaction. • Well-dispersed catalytic active sites, geometric and electronic modification gave rise to superb electrocatalytic activity. • MnO/Co-CNTs afforded excellent performance for rechargeable Zn-air battery. [ABSTRACT FROM AUTHOR]

Utility lead-carbon batteries in renewable energy storage applications require fast charge ability and long-term cycling stability, which introduces a fundamental problem that how to improve the electrode kinetics and cycling stability of lead-carbon electrode. Herein, we present an oxygen-deficient PbO decorated rice-husk-based hierarchical porous carbon (RHHPC@PbO 1-x) composite as an effective additive of negative electrode in lead-carbon battery. The RHHPC@PbO 1-x composite was prepared from a facile sol-gel/annealing method. The obtained RHHPC@PbO 1-x composite and the lead-carbon electrode with RHHPC@PbO 1-x additives were characterized by various physicochemical methods, such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and multiple electrochemical methods. The RHHPC@PbO 1-x composite enhances the electrochemical active surface area and strengthens the structural stability of lead-carbon electrode, which improves the electrode kinetics and the cycling stability of lead-carbon negative electrode. As a result, the cycling life of a 2 V/4 Ah valve-regulated lead-carbon battery with RHHPC@PbO 1-x composite additives exhibited a lifespan of 900 cycles (triple of the blank battery). Our work gives an insight for interphase and porosity tuning of lead-carbon additives used in lead-carbon battery. Based on the existing mature production facilities of lead-acid battery, it is promising for this RHHPC@PbO 1-x additive to be used in commercial lead-carbon batteryies for renewable energy storage. • The RHHPC@PbO 1-x inhibits the hydrogen evolution of lead-carbon electrode. • Robust composite interphase of RHHPC@PbO 1-x builds good conductive network. • Lead oxide is deposited evenly on the surface of RHHPC@PbO 1-x. • Hierarchical porous structure increases the kinetic activity of Pb/PbSO 4. • Lead-carbon battery with RHHPC@PbO 1-x shows excellent cycling stability. [ABSTRACT FROM AUTHOR]

Magnetic ZnFe 2 O 4 @ZnSe hollow nanospheres were fabricated by a two-step method and applied for visible light photocatalytic water splitting. Magnetic ZnFe 2 O 4 hollow nanosphere was prepared by using the carbonaceous microsphere as a template, and ZnSe nanoparticles were in site grown on the ZnFe 2 O 4 surface. Through optimizing the reaction time, ZnFe 2 O 4 @ZnSe hollow nanospheres exhibited efficient light absorption and improved photocatalytic performance, and ZnFe 2 O 4 @ZnSe-20 with suitable ZnSe shell thickness possessed highest hydrogen production amount in 6 h (16897.3 μmol/g). The experimental results revealed that the formation of heterojunction between ZnSe and ZnFe 2 O 4 effectively separated and transferred the photo-induced electrons and holes, and inhibited the electron-hole pairs recombination. In addition, the magnetic recyclability of ZnFe 2 O 4 @ZnSe hollow nanospheres was beneficial to further photocatalytic hydrogen production application. Display Omitted • ZnFe 2 O 4 @ZnSe hollow nanospheres exhibited enhanced photocatalytic hydrogen evolution efficiency. • The formation of heterojunction between ZnFe 2 O 4 and ZnSe effectively suppressed the electron-hole pairs recombination. • ZnFe 2 O 4 @ZnSe hollow nanospheres with excellent ferromagnetic property could be easily separated and recycled. [ABSTRACT FROM AUTHOR]