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Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi‐step catalytic reactions. Here, we report a defect‐derived strategy for creating surface phosphorous vacancies (P‐vacancies) on nanometric Rh2P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P‐terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P‐terminated Rh2P{200} facets (p‐Rh2P) can be bypassed on defective Rh2P{200} surfaces (d‐Rh2P). The P‐vacancies enable the exposure of sub‐surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P‐sites to effectively accelerate the alkaline HOR. Defective Rh2P nanowires (d‐Rh2P NWs) and perfect Rh2P nanocubes (p‐Rh2P NCs) are then elaborately synthesized to experimentally represent the d‐Rh2P and p‐Rh2P catalytic surfaces. As expected, the P‐vacancy‐enriched d‐Rh2P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p‐Rh2P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • The porous Cu 2 O-HNSs were facilely prepared through a one-pot wet-chemical method. • The concentration of NH 2 OH∙HCl and pH value play critical roles in the synthesis. • Compared to Cu powder, Cu 2 O-HNSs showed an enhanced CER performance for C 2 products. • The type of electrode and carbon support can impact the CER performance of Cu 2 O-HNSs. In this paper, porous Cu 2 O hollow nanospheres (Cu 2 O-HNSs) were facilely synthesized through a template-free one-pot wet-chemical method. Systematical investigations found that Cu 2 O-HNSs with many cavities on the shell were formed from porous Cu 2 O nanospheres through Ostwald ripening. The concentration of NH 2 OH∙HCl and pH value play critical roles. Compared to Cu powder, Cu 2 O-HNSs showed enhanced current density and Faraday efficiency of C 2 products in electroreduction of CO 2 (CER). Our work inspires the synthesis of hollow nanostructures to accelerate the formation of C 2 products for CER. [ABSTRACT FROM AUTHOR]

Diabetic wounds are complications of diabetes which are caused by skin dystrophy because of local ischemia and hypoxia. Diabetes causes wounds in a pathological state of inflammation, resulting in delayed wound healing. The structure of electrospun nanofibers is similar to that of the extracellular matrix (ECM), which is conducive to the attachment, growth, and migration of fibroblasts, thus favoring the formation of new skin tissue at the wound. The composition and size of electrospun nanofiber membranes can be easily adjusted, and the controlled release of loaded drugs can be realized by regulating the fiber structure. The porous structure of the fiber membrane is beneficial to gas exchange and exudate absorption at the wound, and the fiber surface can be easily modified to give it function. Electrospun fibers can be used as wound dressing and have great application potential in the treatment of diabetic wounds. In this study, the applications of polymer electrospun fibers, nanoparticle-loaded electrospun fibers, drug-loaded electrospun fibers, and cell-loaded electrospun fibers, in the treatment of diabetic wounds were reviewed, and provide new ideas for the effective treatment of diabetic wounds. [ABSTRACT FROM AUTHOR]

A two-dimensional template-directed oriented self-sacrificial mechanism is successfully developed for the synthesis of one-dimensional kink-rich Pd 3 Pb nanowires (NWs) featuring rich grain boundary defects. Merits such as abundant electroactive defective hot spots and electronic interactions between Pd and Pb atoms endow the Pd 3 Pb NWs with outstanding electrocatalytic performance toward the oxygen reduction reaction. [Display omitted] Developing facile synthetic strategies toward ultrafine one-dimensional (1D) nanowires (NWs) with rich catalytic hot spots is pivotal for exploring effective heterogeneous catalysts. Herein, we demonstrate a two-dimensional (2D) template-directed strategy for synthesizing 1D kink-rich Pd 3 Pb NWs with abundant grain boundaries to serve as high-efficiency electrocatalysts toward oxygen reduction reaction (ORR). In this one-pot synthesis, ultrathin Pd nanosheets were initially generated, which then served as self-sacrificial 2D nano-templates. A dynamic equilibrium growth was subsequently established on the 2D Pd nanosheets through the center-selected etching of Pd atoms and edge-preferred co-deposition of Pd/Pb atoms. This was followed by the oriented attachment of the generated Pd/Pb alloy nanograins and fragments. Thus, kink-rich Pd 3 Pb NWs with rich grain boundary defects were obtained in high yield, and these NWs were used as electrocatalytic active catalysts. The surface electronic interaction between Pd and Pb atoms effectively decreased the surface d -band center to weaken the binding of oxygen-containing intermediates toward improved ORR kinetics. Specifically, the kink-rich Pd 3 Pb NWs/C catalyst delivered outstanding ORR mass activity and specific activity (2.26 A⋅mg Pd −1 and 2.59 mA⋅cm−2, respectively) in an alkaline solution. These values were respectively 13.3 and 10.8 times those of state-of-the-art commercial Pt/C catalyst. This study provides an innovative strategy for fabricating defect-rich low-dimensional nanocatalysts for efficient energy conversion catalysis. [ABSTRACT FROM AUTHOR]