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Exploiting efficient electrocatalysts for hydrogen peroxide (H2O2) electroproduction by oxygen reduction reaction (ORR) is highly desired in practical application. Herein, nitrogen- and fluoride-codoped carbon nanocages (NF-Cs) are successfully synthesized through a simple and scalable template method. With the aid of a porous structure, a large surface area, and the introduction of N and F atoms, NF-Cs show excellent electrocatalytic performance for H2O2 electroproduction in alkaline solution (pH 13) with a faradaic efficiency of 89.6% at very positive applied potential (0.74 V). In acid solution (pH 0.35), the faradaic efficiency of H2O2 electroproduction stably maintains at 85%–88% in the range of 0.4–0.72 V potential. The experimental and theoretical results reveal that the strong synergistic effect between the doped N and F atoms facilitate the H2O2 electroproduction through 2e ORR. That is, the doped N atoms promote O2 molecule adsorption on the catalyst surface, and the F atoms facilitate the desorption of the *OOH intermediate, which is the key factor for the NF-Cs efficiently catalyzing H2O2 electroproduction. These results provide beneficial references for reasonably designing effective carbon-based electrocatalysts for H2O2 electroproduction.

Single-crystalline vanadium oxide nanobelts were obtained through a surfactant-directed growth process under hydrothermal conditions using V 2 O 5 as a precursor. The shape and size were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), ultraviolet/ visible (UV/vis) spectroscopy, X-ray photoelecton spectroscopy (XPS), high-resolution TEM (HRTEM), and selected area electron diffraction (SAED) were used to characterize the composition and structure of the as-prepared nanobelts. The as-obtained vanadium oxide nanobelts are up to several hundreds of micrometers in length, 100-200 nm in diameter, and 20-30 nm in thickness. A possible mechanism was proposed to account for the formation of the nanobelts. The influence of the concentration of reactants, the reaction time, the concentration of the surfactant, and the reaction temperature on the morphology of the resulting products are discussed in detail. Furthermore, we tested the electrochemical intercalation properties with Li + of the postannealing sample by calcining the obtained vanadium oxide nanobelts at 400 °C. It was found that the morphology and the structure of the synthesized product had an important influence on the electrochemical intercalation properties.

The efficient electrocatalysts toward the ethylene glycol oxidation reaction (EGOR) are highly desirable for direct ethylene glycol fuel cells because of the sluggish kinetics of anodic EGOR. Herein, porous RhCu nanoboxes are successfully prepared through facile galvanic replacement reaction and succedent sodium borohydride reduction strategy. Benefiting from hierarchical pore structure, RhCu nanoboxes display excellent electrocatalytic performance toward the EGOR in alkaline medium with a mass activity of 775.1 A gRh−1, which is 2.8 times as large as that of commercial Rh nanocrystals. Moreover, the long‐term stability of RhCu nanoboxes is better than that of commercial Rh nanocrystals. Furthermore, the theoretical calculations demonstrate that RhCu nanoboxes possess lower adsorption energy of CO and lower reaction barrier (0.27 eV) for the COads oxidation with aid of the adsorbed OHads species, resulting in the outstanding electrocatalytic performance toward the EGOR. This work provides a meaningful reference for developing highly effective electrocatalysts toward the EGOR.