Djurleite Copper Sulfide-Coupled Cobalt Sulfide Interface for a Stable and Efficient Electrocatalyst.

Transition metal sulfides (TMS) exhibit proliferated edge sites, facile electrode kinetics, and improved intrinsic electrical conductivity, which demand low potential requirements for total water splitting application. Here, we have propounded copper sulfide-coupled cobalt sulfide nanosheets grown on 3D nickel as an electrocatalyst for hydrogen (HER) and oxygen evolution (OER) reactions. The formation of djurleite copper sulfide with a Cu vacancy enables faster H ion transport and shows improved HER activity with a remarkably lower overpotential of 164 mV at 10 mA/cm, whereas cobalt-incorporated copper sulfide undergoes cation exchange during synthesis and shows elevated OER activity with a lower overpotential of 240 mV at 10 mA/cm for the OER.

Cation intercalated one-dimensional manganese hydroxide nanorods and hierarchical mesoporous activated carbon nanosheets with ultrahigh capacitance retention asymmetric supercapacitors.

We have reported the electrochemical performance of K ion doped Mn(OH) and MnO nanorods as a positive electrode and a highly porous activated carbon nanosheet (AC) made from Prosopis Juliflora as negative electrode asymmetric supercapacitor (ASC) with high rate capability and capacity retention. The cation K doped Mn(OH) and MnO nanorods with large tunnel sizes allow the electrolyte to penetrate through a well-defined pathway and hence benefits from the intercalation pseudocapacitance and surface redox reactions. As a result, they exhibit good electrochemical performance in neutral aqueous electrolytes.

Revealing the Self-Degradation Mechanisms in Methylammonium Lead Iodide Perovskites in Dark and Vacuum.

Organic-inorganic lead halide perovskite phases segregate (and their structures degrade) under illumination, exhibiting a poor stability with hysteresis and producing halide accumulation at the surface.In this work, we observed structural and interfacial dissociation in methylammonium lead iodide (CH NH PbI ) perovskites even under dark and vacuum conditions. Here, we investigate the origin and consequences of self-degradation in CH NH PbI perovskites stored in the dark under vacuum.

Artificial semiconductor/insulator superlattice channel structure for high-performance oxide thin-film transistors.

High-performance thin-film transistors (TFTs) are the fundamental building blocks in realizing the potential applications of the next-generation displays. Atomically controlled superlattice structures are expected to induce advanced electric and optical performance due to two-dimensional electron gas system, resulting in high-electron mobility transistors. Here, we have utilized a semiconductor/insulator superlattice channel structure comprising of ZnO/Al2O3 layers to realize high-performance TFTs.

Wettability control and water droplet dynamics on SiC-SiO2 core-shell nanowires.

We present a simple method for fabricating superhydrophobic SiC-SiO(2) core-shell nanowire surfaces via the facile dip-coating of alkyltrichlorosilanes. Water droplets displayed a variety of shapes with varying surface energies on the nanowire surfaces, which could be modified through chemisorption of alkyltrichlorosilanes with variable carbon chain length. The effects of UV irradiation on the superhydrophobic nanowire arrays were also investigated.

Synthesis and Characterization of ZnO Nanowire-CdO Composite Nanostructures.

ZnO nanowire-CdO composite nanostructures were fabricated by a simple two-step process involving ammonia solution method and thermal evaporation. First, ZnO nanowires (NWs) were grown on Si substrate by aqueous ammonia solution method and then CdO was deposited on these ZnO NWs by thermal evaporation of cadmium chloride powder. The surface morphology and structure of the synthesized composite structures were analyzed by scanning electron microscopy, X-ray diffraction and transmission electron microscopy.

Synthesis of Novel Double-Layer Nanostructures of SiC-WO(x) by a Two Step Thermal Evaporation Process.

A novel double-layer nanostructure of silicon carbide and tungsten oxide is synthesized by a two-step thermal evaporation process using NiO as the catalyst. First, SiC nanowires are grown on Si substrate and then high density W(18)O(49) nanorods are grown on these SiC nanowires to form a double-layer nanostructure. XRD and TEM analysis revealed that the synthesized nanostructures are well crystalline.

Growth and characterization of stoichiometric tungsten oxide nanorods by thermal evaporation and subsequent annealing.

Stoichiometric tungsten oxide (WO(3)) nanorods are synthesized on tungsten (W) substrates by a high-temperature, catalyst-free, physical deposition process and by subsequent annealing in oxygen atmosphere. Tungsten oxide nanorods are grown by thermal evaporation of WO(3) powder at elevated temperature in a tube furnace. XRD, TEM and XPS analysis shows that the as-grown nanorods are single crystalline and non-stoichiometric (WO(x)).