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The efficient electrosynthesis of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (2e− ORR) in neutral media is undoubtedly a practical route, but the limited comprehension of electrocatalysts has hindered the system advancement. Herein, we present the design of model catalysts comprising mesoporous carbon spheres‐supported Pd nanoparticles for H2O2 electrosynthesis at near‐zero overpotential with approximately 95 % selectivity in a neutral electrolyte. Impressively, the optimized Pd/MCS‐8 electrocatalyst in a flow cell device achieves an exceptional H2O2 yield of 15.77 mol gcatalyst−1 h−1, generating a neutral H2O2 solution with an accumulated concentration of 6.43 wt %, a level sufficiently high for medical disinfection. Finite element simulation and experimental results suggest that mesoporous carbon carriers promote O2 enrichment and localized pH elevation, establishing a favorable microenvironment for 2e− ORR in neutral media. Density functional theory calculations reveal that the robust interaction between Pd nanoparticles and the carbon carriers optimized the adsorption of OOH* at the carbon edge, ensuring high active 2e− process. These findings offer new insights into carbon‐loaded electrocatalysts for efficient 2e− ORR in neutral media, emphasizing the role of carrier engineering in constructing favorable microenvironments and synergizing active sites. [ABSTRACT FROM AUTHOR]

The controllable anchoring of multiple metal single‐atoms (SAs) into a single support exhibits scientific and technological opportunities, while marrying the concentration‐complex multimetallic SAs and high‐entropy SAs (HESAs) into one SAC system remains a substantial challenge. Here, we present a substrate‐mediated SAs formation strategy to successfully fabricate a library of multimetallic SAs and HESAs on MoS2 and MoSe2 supports, which can precisely control the doping location of SAs. Specially, the contents of SAs can continuously increase until the accessible Mo atoms on TMDs carriers are completely replaced by SAs, thus allowing the of much higher metal contents. In‐depth mechanistic study shows that the well‐controlled synthesis of multimetallic SAs and HESAs is realized by controlling the reversible redox reaction occurred on the TMDs/TM ion interface. As a proof‐of‐concept application, a variety of SAs‐TMDs were applied to hydrogen evolution reaction. The optimized HESAs‐TMDs (Pt,Ru,Rh,Pd,Re‐MoSe2) delivers a much higher activity and durability than state of‐the‐art Pt. Thus, our work will broaden the family of single‐atom catalysts and provide a new guideline for the rational design of high‐performance single‐atom catalysts. [ABSTRACT FROM AUTHOR]

Heteroatom doping has emerged as a highly effective strategy to enhance the activity of metal‐based electrocatalysts toward the oxygen evolution reaction (OER). It is widely accepted that the doping does not switch the OER mechanism from the adsorbate evolution mechanism (AEM) to the lattice‐oxygen‐mediated mechanism (LOM), and the enhanced activity is attributed to the optimized binding energies toward oxygen intermediates. However, this seems inconsistent with the fact that the overpotential of doped OER electrocatalysts (<300 mV) is considerably smaller than the limit of AEM (>370 mV). To determine the origin of this inconsistency, we select phosphorus (P)‐doped nickel‐iron mixed oxides as the model electrocatalysts and observe that the doping enhances the covalency of the metal‐oxygen bonds to drive the OER pathway transition from the AEM to the LOM, thereby breaking the adsorption linear relation between *OH and *OOH in the AEM. Consequently, the obtained P‐doped oxides display a small overpotential of 237 mV at 10 mA cm−2. Beyond P, the similar pathway transition is also observed on the sulfur doping. These findings offer new insights into the substantially enhanced OER activity originating from heteroatom doping. [ABSTRACT FROM AUTHOR]

Synergy engineering is an important way to enhance the kinetic activity of oxygen‐evolution‐reaction (OER) electrocatalysts. Here, we fabricated NiFe amorphous nanoreactor (NiFe‐ANR) oxide as OER electrocatalysts via a mild self‐catalytic reaction. Firstly, the amorphousness helps transform NiFe‐ANR into highly active hydroxyhydroxides, and its many fine‐grain boundaries increase active sites. More importantly, as proved by experiments and finite element analysis, the nanoreactor structure alters the spatial curvature and the mass transfer over the catalyst, thereby enriching OH− in the catalyst surface and inner part. Thus, the catalyst with the structure of amorphous nanoreactors gained excellent activity, far superior to the NiFe catalyst with the structure of crystalline nanoreactor or amorphous non‐nanoreactor. This work provides new insights into the applications and mechanisms of amorphousness and nanoreactors, embodying the "1+1>2" synergy of crystalline state and morphology. [ABSTRACT FROM AUTHOR]

Previous density‐functional theory (DFT) calculations show that sub‐nanometric Cu clusters (i.e. 13 atoms) favorably generate CH4 from the CO2 reduction reaction (CO2RR), but experimental evidence is lacking. Herein, a facile impregnation‐calcination route towards Cu clusters, having a diameter of about 1.0 nm with about 10 atoms, was developed by double confinement of carbon defects and micropores. These Cu clusters enable high selectivity for the CO2RR with a maximum Faraday efficiency of 81.7 % for CH4. Calculations and experimental results show that the Cu clusters enhance the adsorption of *H and *CO intermediates, thus promoting generation of CH4 rather than H2 and CO. The strong interactions between the Cu clusters and defective carbon optimize the electronic structure of the Cu clusters for selectivity and stability towards generation of CH4. Provided here is the first experimental evidence that sub‐nanometric Cu clusters facilitate the production of CH4 from the CO2RR. [ABSTRACT FROM AUTHOR]

Bioinspired unidirectional porous materials have emerged as a unique class of scaffolds for the fabrication of macroscopic nanomaterial assemblies. However, these scaffolds usually serve simply as mechanical carriers to support various building blocks. Here, we report that the unidirectional silk fibroin scaffold can not only act as a carrier, but also serve as a controllable multiscale reactor to achieve the in situ synthesis of a Ag3PO4 nanowire network anchored to ordered channels. Both the silk fibroin matrix and the interface play important roles in the nucleation and growth of the Ag3PO4 nanowires. This unidirectional composite scaffold can be used for efficient water disinfection. Furthermore, the facile chemical transformation of Ag3PO4 in the composite scaffold into Ag2S provided an analogous unidirectional composite silk scaffold that displays both efficient solar water evaporation effect and antibacterial activity. It is expected that this method can be extended to fabricate a series of silk‐based unidirectional composite scaffolds with varying functionalities. [ABSTRACT FROM AUTHOR]

Recently, metal‐free, heteroatom‐doped carbon nanomaterials have emerged as promising electrocatalysts for the oxygen evolution reaction (OER), but their synthesis is a tedious process involving energy‐wasting calcination. Molecular electrocatalysts offer attractive catalysts for the OER. Here, phytic acid (PA) was selected to investigate the OER activity of carbons in organic molecules by DFT calculations and experiments. Positively charged carbons on PA were very active towards the OER. The PA molecules were fixed into a porous, conductive hydrogel with a superhydrophilic surface. This outperformed most metal‐free electrocatalysts. Besides the active sites on PA, the high OER activity was also related to the porous and conductive networks on the hydrogel, which allowed fast charge and mass transport during the OER. Therefore, this work provides a metal‐free, organic‐molecule‐based electrocatalyst to replace carbon nanomaterials for efficient OER. Positively charged carbons on organic molecules (i.e. phytic acid, denoted PA) can participate in the oxygen evolution reaction (OER), as shown by DFT calculations and experiments. Moreover, doping of PA into a porous and conductive hydrogel is a robust strategy for stabilizing PA, as well as boosting the charge and mass transport of PA during the OER. [ABSTRACT FROM AUTHOR]

A facile route to scalable production of N and S co‐doped, hierarchically porous carbon nanofiber (NSHCF) membranes (ca. 400 cm2 membrane in a single process) is reported. As‐synthesized NSHCF membranes are flexible and free‐standing, allowing their direct use as cathodes for efficient electrochemical CO2 reduction reaction (CO2RR). Notably, CO with 94 % Faradaic efficiency and −103 mA cm−2 current density are readily achieved with only about 1.2 mg catalyst loading, which are among the best results ever obtained by metal‐free CO2RR catalysts. On the basis of control experiments and DFT calculations, such outstanding CO Faradaic efficiency can be attributed to the co‐doped pyridinic N and carbon‐bonded S atoms, which effectively decrease the Gibbs free energy of key *COOH intermediate. Furthermore, hierarchically porous structures of NSHCF membranes impart a much higher density of accessible active sites for CO2RR, leading to the ultra‐high current density. An effective method was developed for scalable production of N, S co‐doped hierarchically porous carbon nanofiber membranes. These membranes are flexible and self‐supporting, and they could be directly used as a cathode for electrochemical CO2 reduction. With a circa 1.2 mg catalyst loading, a 94 % Faradaic efficiency and −103 mA cm−2 current density was obtained, which are among the best results for metal‐free CO2RR catalysts. [ABSTRACT FROM AUTHOR]