The lack of suitable cathodes is one of the key reasons that impede the development of aqueous zinc-ion batteries. Because of the inherently unsuitable structure and inferior physicochemical properties, the low-valent V2O3 as Zn2+ host could not be effectively discharged. Herein, we demonstrate that V2O3 (theoretical capacity up to 715 mAh g–1) can be utilized as a high-performance cathode material by an in situ anodic oxidation strategy. Through simultaneously regulating the concentration of the electrolyte and the morphology of the V2O3 sample, the ultraefficient anodic oxidation process of the V2O3 cathode was achieved within the first charging, and the mechanism was also schematically investigated. As expected, the V2O3 cathode with a hierarchical microcuboid structure achieved a nearly two-electron transfer process, enabling a high discharging capacity of 625 mAh g–1 at 0.1 A g–1 (corresponding to a high energy density of 406 Wh kg–1) and cycling stability (100% capacity retention after 10 000 cycles). This work not only sheds light on the phase transition process of low-valent V2O3 but also exploits a method toward design of advanced cathode materials.

A photocatalytic strategy has been developed to synthesize colloidal Ag-TiO2 nanorod composites in which each TiO2 nanorod contains a single Ag nanoparticle on its surface. In this rational synthesis, photoexcitation of TiO2 nanorods under UV illumination produces electrons that reduce Ag(I) precursor and deposit multiple small Ag nanoparticles on the surface of TiO2 nanorods. Prolonged UV irradiation induces an interesting ripening process, which dissolves the smaller nanoparticles by photogenerated oxidative species and then redeposits Ag onto one larger and more stable particle attached to each TiO2 nanorod through the reduction of photoexcited electrons. The size of the Ag nanoparticles can be precisely controlled by varying the irradiation time and the amount of alcohol additive. The Ag-TiO2 nanorod composites were used as electron transport layers in the fabrication of organic solar cells and showed notable enhancement in power conversion efficiency (6.92%) than pure TiO2 nanorods (5.81%), as well as higher external quantum efficiency due to improved charge separation and transfer by the presence of Ag nanoparticles.

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One-dimensional (1D) carbon nanomaterials wrapped by silver nanoparticles were fabricated via a facile and environmentally benign route with the assistance of supercritical carbon dioxide. Transmission electron microscopy, scanning electron microscopy, and energy-dispersive X-ray analysis revealed that carbon nanofibers (CNFs) were densely coated by silver nanoparticles under the optimized experimental condition. In the case of carbon nanotube/silver (CNT/Ag) nanohybrids, these silver nanoparticles on the surface of carbon nanotubes were predominantly spherical in shape with excellent dispersion, and their sizes were smaller than that on carbon nanofibers. The UV−vis spectra presented a surface plasmon resonance vibration band at 448 and 414 nm for CNFs and CNTs, respectively. X-ray diffraction analysis showed that the nanoparticles were of a face centered cubic structure. Some crucial factors, which affect the growing and arraying of Ag nanoparticles along the axis of 1D carbon nanomaterials, had been investigated. As examples for promising applications, the antibacterial activities of the as-prepared one-dimensional nanocomposites were also studied.