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The high theoretical energy density (1274 Wh kg−1) and high safety enable the all‐solid‐state Na−S batteries with great promise for stationary energy storage system. However, the uncontrollable solid–liquid‐solid multiphase conversion and its associated sluggish polysulfides redox kinetics pose a great challenge in tunning the sulfur speciation pathway for practical Na−S electrochemistry. Herein, we propose a new design methodology for matrix featuring separated bi‐catalytic sites that control the multi‐step polysulfide transformation in tandem and direct quasi‐solid reversible sulfur conversion during battery cycling. It is revealed that the N, P heteroatom hotspots are more favorable for catalyzing the long‐chain polysulfides reduction, while PtNi nanocrystals manipulate the direct and full Na2S4 to Na2S low‐kinetic conversion during discharging. The electrodeposited Na2S on strongly coupled PtNi and N, P‐codoped carbon host is extremely electroreactive and can be readily recovered back to S8 without passivation of active species during battery recharging, which delivers a true tandem electrocatalytic quasi‐solid sulfur conversion mechanism. Accordingly, stable cycling of the all‐solid‐state soft‐package Na−S pouch cells with an attractive specific capacity of 876 mAh gS−1 and a high energy of 608 Wh kgcathode−1 (172 Wh kg−1, based on the total mass of cathode and anode) at 60 °C are demonstrated. [ABSTRACT FROM AUTHOR]

The high theoretical energy density (1274 Wh kg−1) and high safety enable the all‐solid‐state Na−S batteries with great promise for stationary energy storage system. However, the uncontrollable solid–liquid‐solid multiphase conversion and its associated sluggish polysulfides redox kinetics pose a great challenge in tunning the sulfur speciation pathway for practical Na−S electrochemistry. Herein, we propose a new design methodology for matrix featuring separated bi‐catalytic sites that control the multi‐step polysulfide transformation in tandem and direct quasi‐solid reversible sulfur conversion during battery cycling. It is revealed that the N, P heteroatom hotspots are more favorable for catalyzing the long‐chain polysulfides reduction, while PtNi nanocrystals manipulate the direct and full Na2S4 to Na2S low‐kinetic conversion during discharging. The electrodeposited Na2S on strongly coupled PtNi and N, P‐codoped carbon host is extremely electroreactive and can be readily recovered back to S8 without passivation of active species during battery recharging, which delivers a true tandem electrocatalytic quasi‐solid sulfur conversion mechanism. Accordingly, stable cycling of the all‐solid‐state soft‐package Na−S pouch cells with an attractive specific capacity of 876 mAh gS−1 and a high energy of 608 Wh kgcathode−1 (172 Wh kg−1, based on the total mass of cathode and anode) at 60 °C are demonstrated. [ABSTRACT FROM AUTHOR]

Nickel‐based catalysts have been regarded as one of the most promising electrocatalysts for urea oxidation reaction (UOR), however, their activity is largely limited by the inevitable self‐oxidation reaction of Ni species (NSOR) during the UOR. Here, we proposed an interface chemistry modulation strategy to trigger the occurrence of UOR before the NSOR via constructing a 2D/2D heterostructure that consists of ultrathin NiO anchored Ru−Co dual‐atom support (Ru‐Co DAS/NiO). Operando spectroscopic characterizations confirm this unique triggering mechanism on the surface of Ru‐Co DAS/NiO. Consequently, the fabricated catalyst exhibits outstanding UOR activity with a low potential of 1.288 V at 10 mA cm−2 and remarkable long‐term durability for more than 330 h operation. DFT calculations and spectroscopic characterizations demonstrate that the favorable electronic structure induced by this unique heterointerface endows the catalyst energetically more favorable for the UOR than the NSOR. [ABSTRACT FROM AUTHOR]

Nickel‐based catalysts have been regarded as one of the most promising electrocatalysts for urea oxidation reaction (UOR), however, their activity is largely limited by the inevitable self‐oxidation reaction of Ni species (NSOR) during the UOR. Here, we proposed an interface chemistry modulation strategy to trigger the occurrence of UOR before the NSOR via constructing a 2D/2D heterostructure that consists of ultrathin NiO anchored Ru−Co dual‐atom support (Ru‐Co DAS/NiO). Operando spectroscopic characterizations confirm this unique triggering mechanism on the surface of Ru‐Co DAS/NiO. Consequently, the fabricated catalyst exhibits outstanding UOR activity with a low potential of 1.288 V at 10 mA cm−2 and remarkable long‐term durability for more than 330 h operation. DFT calculations and spectroscopic characterizations demonstrate that the favorable electronic structure induced by this unique heterointerface endows the catalyst energetically more favorable for the UOR than the NSOR. [ABSTRACT FROM AUTHOR]

Manipulating the coordination environment of the active center via anion modulation to reveal tailored activity and selectivity has been widely achieved, especially for carbon‐based single‐atom site catalysts (SACs). However, tuning ligand fields of the active center by single‐site metal cation regulation and identifying the effects on the resulting electronic configuration is seldom explored. Herein, we propose a single‐site Ru cation coordination strategy to engineer the electronic properties by constructing a Ru/LiCoO2 SAC with atomically dispersed Ru−Co pair sites. Benefitting from the strong electronic coupling between Ru and Co sites, the catalyst possesses an enhanced electrical conductivity and achieves near‐optimal oxygen adsorption energies. Therefore, the optimized catalyst delivers superior oxygen evolution reaction (OER) activity with low overpotential, the high mass activity of 1000 A goxide−1 at a small overpotential of 335 mV, and excellent long‐term stability. It also exhibits rapid kinetics with superior rate capability and outstanding durability in a zinc–air battery. [ABSTRACT FROM AUTHOR]

Manipulating the coordination environment of the active center via anion modulation to reveal tailored activity and selectivity has been widely achieved, especially for carbon‐based single‐atom site catalysts (SACs). However, tuning ligand fields of the active center by single‐site metal cation regulation and identifying the effects on the resulting electronic configuration is seldom explored. Herein, we propose a single‐site Ru cation coordination strategy to engineer the electronic properties by constructing a Ru/LiCoO2 SAC with atomically dispersed Ru−Co pair sites. Benefitting from the strong electronic coupling between Ru and Co sites, the catalyst possesses an enhanced electrical conductivity and achieves near‐optimal oxygen adsorption energies. Therefore, the optimized catalyst delivers superior oxygen evolution reaction (OER) activity with low overpotential, the high mass activity of 1000 A goxide−1 at a small overpotential of 335 mV, and excellent long‐term stability. It also exhibits rapid kinetics with superior rate capability and outstanding durability in a zinc–air battery. [ABSTRACT FROM AUTHOR]

The electrochemical CO2 reduction reaction to produce CO is one of the most promising pathways to eliminate CO2 emissions and store intermittent energy sources. However, the most critical usage of CO is via mixing with H2 to form syngas, which is a crucial feedstock for many value‐added chemicals. Therefore, producing syngas with a suitable CO/H2 ratio in a one‐step reaction is desirable in the CO2RR process. To achieve this end, dual single‐atom sites supported by the nitrogen‐doped carbon show great potential. Herein, we show that a dual single‐atom catalyst with Bi−N4 and Zn−N4 units is efficient for generating syngas with tunable CO/H2 ratios (0.20 to 2.92), which is of great significance to downstream industrial production. Moreover, this work highlights the potential to control the CO/H2 ratios for efficient syngas production using the coexisting single‐atom sites. [ABSTRACT FROM AUTHOR]

The in‐depth understanding of local atomic environment–property relationships of p‐block metal single‐atom catalysts toward the 2 e− oxygen reduction reaction (ORR) has rarely been reported. Here, guided by first‐principles calculations, we develop a heteroatom‐modified In‐based metal–organic framework‐assisted approach to accurately synthesize an optimal catalyst, in which single In atoms are anchored by combined N,S‐dual first coordination and B second coordination supported by the hollow carbon rods (In SAs/NSBC). The In SAs/NSBC catalyst exhibits a high H2O2 selectivity of above 95 % in a wide range of pH. Furthermore, the In SAs/NSBC‐modified natural air diffusion electrode exhibits an unprecedented production rate of 6.49 mol peroxide gcatalyst−1 h−1 in 0.1 M KOH electrolyte and 6.71 mol peroxide gcatalyst−1 h−1 in 0.1 M PBS electrolyte. This strategy enables the design of next‐generation high‐performance single‐atom materials, and provides practical guidance for H2O2 electrosynthesis. [ABSTRACT FROM AUTHOR]

The in‐depth understanding of local atomic environment–property relationships of p‐block metal single‐atom catalysts toward the 2 e− oxygen reduction reaction (ORR) has rarely been reported. Here, guided by first‐principles calculations, we develop a heteroatom‐modified In‐based metal–organic framework‐assisted approach to accurately synthesize an optimal catalyst, in which single In atoms are anchored by combined N,S‐dual first coordination and B second coordination supported by the hollow carbon rods (In SAs/NSBC). The In SAs/NSBC catalyst exhibits a high H2O2 selectivity of above 95 % in a wide range of pH. Furthermore, the In SAs/NSBC‐modified natural air diffusion electrode exhibits an unprecedented production rate of 6.49 mol peroxide gcatalyst−1 h−1 in 0.1 M KOH electrolyte and 6.71 mol peroxide gcatalyst−1 h−1 in 0.1 M PBS electrolyte. This strategy enables the design of next‐generation high‐performance single‐atom materials, and provides practical guidance for H2O2 electrosynthesis. [ABSTRACT FROM AUTHOR]

Here we report a synthetic strategy for controllable construction of yolk-shell and core-shell plasmonic metal@semiconductor hybrid nanocrystals through modulating the kinetics of sulfurization reaction followed by cation exchange. The yielded yolk-shell structured products feature exceptional crystallinity and more importantly, the intimately adjoined and sharp interface between plasmonic metal and semiconductor which facilitates efficient charge carrier communications between them. By exploiting the system composed of Au nanorods and p-type PbS as a demonstration, we show that the Au@PbS yolk-shell nanorods manifest notable improvement in visible and near infrared light absorption compared to the Au@PbS core-shell nanorods as well as hollow PbS nanorods. Moreover, the photocathode constituted by Au@PbS yolk-shell nanorods affords the highest photoelectrochemical activities both under simulated sunlight and λ < 700 nm light irradiation. The superior performance of Au@PbS yolk-shell nanorods is considered arising from the combination of the favorable structural advantages of yolk-shell configuration and the surface plasmon resonance enhancement effect. We envision that the reported synthetic strategy can offer a valuable means to create hybrid nanocrystals with desirable structures and functions that enable to harness the photogenerated charge carriers, including the plasmonic hot holes, in wide-range solar-to-fuel conversion. [ABSTRACT FROM AUTHOR]

Here we show a novel strategy for tailoring the synergistic electrical properties of metal@semiconductor hybrid nanocrystals (HNCs) based on cation exchange-enabled electronic doping. As a demonstration, the conductive nature of Au@CdS core–shell HNCs was changed from n- to p-type by introducing Cu dopants into the CdS shell. The dependence of the conductivity type on the dopant concentration in the HNCs is disclosed by combined photoelectrochemical (PEC) studies. Moreover, a tandem PEC cell consisting of an undoped Au@CdS photoanode and a Cu-doped Au@CdS photocathode respectively modified with cocatalysts is fabricated, which displayed stable H2 and O2 evolution in unassisted PEC overall water splitting. [ABSTRACT FROM AUTHOR]

Construction of hollow anisotropic semiconductor nanostructures that possess excellent crystallinity, a flexibly tunable structure/morphology and aqueous dispersity is of special interest for many promising applications such as photoelectrochemical (PEC) water splitting, but has long been hindered by great synthetic challenges. Here we report a powerful and widely applicable approach to fulfill this vision based on cation exchange-induced oxidative etching. Aqueous cation exchange is utilized to chemically convert the shells growing around the shape-controlled Ag templates (such as 2D Ag triangle nanoprisms) into desired semiconductor components (MS, M = Cd and Zn). Remarkably, we found that the soft base ligand used to initiate the cation exchange process can simultaneously induce oxidative etching of the Ag domain forming anisotropic Ag@MS core–shell hybrid nanocrystals, Ag@MS partially hollow hybrid nanocrystals with a controlled degree of hollowness, and hollow MS nanocrystals, depending on the strength of oxidative etching. The resulting core–shell or hollow nanoprisms all exhibit well-defined geometry and crystallinity/interface properties, and this is presumed to be the major reason for their highly efficient performance as the photoanode materials for PEC hydrogen generation. [ABSTRACT FROM AUTHOR]

Multinary chalcogenide semiconductors (MCSs) recently emerged as a promising alternative to their binary counterparts for designing innovative solar energy conversion platforms due to a number of advantages including high absorption coefficient over a broad spectral range, conveniently tunable band structures through alloying, and nontoxicity for their use in real-world settings. The integration of MCSs with plasmonic metals into heteronanostructures is essential for promoting their light harvesting and conversion performance; however it is constrained by the large synthetic impediment arising from the incompatible activities of multiple precursors involved in growing the MCS domain via direct synthesis. Here using Au@Ag2ZnSnS4 core–shell nanocrystals (NCs) as a proof-of-concept demonstration, we report a new synthetic tactic based on cation exchange to access metal@MCS hybrid NCs with exceptional uniformity and precise control over the structural characteristics (both dimensions and morphology) in an aqueous environment. The prepared materials were explored as photoanodes for photoelectrochemical (PEC) hydrogen evolution, and the results suggested that our approach offers a good opportunity to unravel the delicate links between solar energy conversion efficiency and the structure of metal@MCS NCs. In view of the great versatility of cation exchange, we envision that this approach can be extended to fabricate a wide variety of metal@MCS NCs with unprecedented structures and functions. [ABSTRACT FROM AUTHOR]

High-activity electrocatalysts with robust structure are critical for development of renewable-energy technologies. Herein, a hybrid of cobalt nanoparticles embedded in N-doped carbon nanotubes (Co@NCNT) was fabricated via economically scalable pyrolysis of a mixture of a Co-based metal–organic framework (ZIF-67) and dicyandiamide. The as-synthesized Co@NCNT hybrid was characterized by techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photon spectroscopy (XPS) etc., confirming that it possessed desirable properties of high surface area, robust structure, and good conductivity. A series of electrochemical measurements demonstrated that the Co@NCNT exhibits high activity and excellent durability toward several important electrochemical reactions, including hydrogen evolution reaction (HER) in pH-universal electrolyte, oxygen reduction reaction (ORR) in both acidic and alkaline media, glucose oxidation reaction (GOR), and oxygen evolution reaction (OER) in alkaline medium, mainly as a result of the synergistic effects of unique structure and high surface area of the Co nanoparticles and nitrogen dopant in the nanocomposite. A zinc–air battery with outstanding performance was set up using the Co@NCNT as cathode material, demonstrating its potential applications in energy storage and as a conversion system device. [ABSTRACT FROM AUTHOR]

In this communication, light harvesting and photoelectrochemical (PEC) hydrogen generation beyond the visible region are realized by an anisotropic plasmonic metal/semiconductor hybrid photocatalyst with precise control of their topology and heterointerface. Controlling the intended configuration of the photocatalytic semiconductor to anisotropic Au nanorods' plasmonic hot spots, through a water phase cation exchange strategy, the site‐selective overgrowth of a CdSe shell evolving from a core/shell to a nanodumbbell is realized successfully. Using this strategy, tip‐preferred efficient photoinduced electron/hole separation and plasmon enhancement can be realized. Thus, the PEC hydrogen generation activity of the Au/CdSe nanodumbbell is 45.29 µmol cm−2 h−1 (nearly 4 times than the core/shell structure) beyond vis (λ > 700 nm) illumination and exhibits a high faradic efficiency of 96% and excellent stability with a constant photocurrent for 5 days. Using surface photovoltage microscopy, it is further demonstrated that the efficient plasmonic hot charge spatial separation, which hot electrons can inject into CdSe semiconductors, leads to excellent performance in the Au/CdSe nanodumbbell. [ABSTRACT FROM AUTHOR]