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In this study, ITO and Pt layers were deposited on (100) Si substrate respectively as bottom electrode for ZnO-based resistive memory. The ITO layer was textured and its preferred orientation is highly dependent on the oxygen partial pressure of growth atmosphere. As the oxygen content increases in the range of 0%–15%, the preferential growth orientation tends to change from (400) to (222). (002)-textured ZnO thin films with different preferred orientation degree sputtered on Pt and two kinds of oriented ITO layers were comparatively investigated. The device with (400)-ITO bottom electrode was found to have the best resistive switching performance. Meanwhile, the differences in switching behaviors were also found to be closely related to the thickness-dependent crystalline structure and top contact electrode/interface. This study provides an in-depth understanding of the structural design and structure-activity relationship of high-performance ZnO-based resistive memory.

Transition metal oxide and porous carbon both with unique structure are hopeful for employing high-performance energy storage devices. In our work, a simple and inexpensive chemical precipitation method was utilized to obtain the ferroferric oxide/carbide-derived carbon (Fe3O4/CDC) composite electrode of supercapacitor. The Fe3O4 nanoparticles with cube shape were embedded in three-dimensional net porous CDC material. Owing to the superior synergistic effect between CDC with high specific surface area and Fe3O4 nanoparticles with high redox activity, the optimal Fe3O4/CDC composite electrode shows good capacitive performances. In the three-electrode system, the Fe3O4/CDC composite electrode exhibits high specific capacitance in neutral Na2SO4 (293.7 F g−1) and alkaline KOH electrolytes (346.5 F g−1) at 1 A g−1. Especially, the Fe3O4/CDC composite shows better electrochemical stability in Na2SO4 electrolyte. The symmetrical supercapacitor was produced by using Na2SO4 as electrolyte and Fe3O4/CDC composite as electrode. The as-produced device offers an excellent energy density of 14.3 Wh kg−1 at 4093 W kg−1. After 4000 cycles, 92.3% of the initial specific capacitance can be retained, proving the remarkable cycle stability. Thus, the effective and facile combination of three-dimensional net porous CDC and Fe3O4 nanoparticles to obtaining electrode material is a promising strategy for efficient energy-storage application.

Specific surface area and electrical conductivity are two decisive factors affecting materials properties. As a potential energy material, MoO3 is still limited in research and application due to its inherent defects. Ag nanoparticles with good electrical conductivity and unique small-size effect are predicted to have more hopeful prospects in energy storage. Ag@MoO3 composites with different Ag content were successfully prepared by a simple liquid-phase reduction method. The results show that the Ag@MoO3 composite has good morphology and the maximum capacitance (225 F/g) when the content of Ag is 8%. Notably, the internal resistance and Warberg resistance of the composite compared with that of MoO3 have been greatly reduced. It is mainly due to the high ion conductivity and small-size effect of Ag nanoparticles, which effectively improve the diffusion efficiency of ions between electrolyte and active materials. Practical application feasibility of Ag@MoO3 electrode was tested in the two-electrode system. Symmetrical coin cell supercapacitor using 8% Ag@MoO3 as electrodes has superior performance. Our work has potential reference value for the combination and characterization of energy storage materials.

Cubic Ag3PO4 microcrystals were synthesized by deposition–precipitation in the presence of ammonia. As-synthesized samples were characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), Raman spectroscopy and UV–visible diffuse reflectance spectroscopy (UV–vis DSR). Visible-light-driven photocatalytic performance of the obtained Ag3PO4 was evaluated for photocatalytic degradation of typical organic dye molecules. Compared to irregular Ag3PO4 materials prepared in the absence of ammonia, the prepared cubic samples exhibited a higher photocatalytic activity, suggesting the crucial role of the ammonia in the formation of cubic Ag3PO4 microcrystals. In addition, the specific cubic morphology of Ag3PO4 sample contributes substantially to its highly efficient visible light photocatalytic performance. Moreover, photocatalytic degradation experiments of the cubic Ag3PO4 toward different organic dye molecules rhodamine B (RhB), methyl blue (MB) and methyl orange (MO) were carried out. These results show that photo-generated active oxygen-containing superoxide radicals and photo-induced holes offer the major contribution to highly efficient visible light photocatalytic activity of Ag3PO4.

SiC nanowires-filled cellular SiCO ceramics were prepared using polyurethane sponge as a porous template infiltrated with silicone resin by pyrolysis at 1400 °C under Ar atmosphere. The pyrolysis temperature was an important parameter affecting the formation of SiC nanowires. The as-prepared sample obtained at 1000 °C was composed of SiCO glasses and turbostratic carbon. The SiCO ceramic was further converted into SiO 2 crystals and amorphous carbon by pyrolysis at 1200 °C. With the increasing pyrolysis temperature, SiC nanocrystals embedded in the non-crystalline SiCO matrix were observed. Furthermore, the SiC nanowires were formed in the pores of the SiCO ceramic. The diameters of the SiC nanowires are in the range 80–150 nm and the lengths are up to several tens of micrometers. The growth mechanism of the nanowires was supported by the vapor-solid mechanism.