Due to its direct and narrow band gap, high chemical stability, and high Seebeck coefficient (1800 μVK−1), antimony selenide (Sb2Se3) has many potential applications, such as in photovoltaic devices, thermoelectric devices, and solar cells. However, research on the Sb2Se3 materials has been limited by its low electrical conductivity in bulk state. To overcome this challenge, we suggest two kinds of nano-structured materials, namely, the diameter-controlled Sb2Se3 nanowires and Ag2Se-decorated Sb2Se3 nanowires. The photocurrent response of diameter-controlled Sb2Se3, which depends on electrical conductivity of the material, increases non-linearly with the diameter of the nanowire. The photosensitivity factor (K = Ilight/Idark) of the intrinsic Sb2Se3 nanowire with diameter of 80–100 nm is highly improved (K = 75). Additionally, the measurement was conducted using a single nanowire under low source-drain voltage. The dark- and photocurrent of the Ag2Se-decorated Sb2Se3 nanowire further increased, as compared to that of the intrinsic Sb2Se3 nanowire, to approximately 50 and 7 times, respectively.

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Figure 3. a) T 1 -weighted image of rat liver obtained by 3-T MRI. b) T 2weighted image and c) corresponding relaxation rate change DR 2 /R 2 of T 2 , which was obtained from (b).

We report the synthesis of Mn x Ni1‑x O and Mn y Co1‑y O alloy nanoparticles by the thermal decomposition of the metal precursor in a surfactant. The different sized and shaped Mn x Ni1‑x O and Mn y Co1‑y O nanoparticles could be obtained by controlling precursors and surfactants. These alloy nanoparticles are antiferromagnetic and their stability is better than that of pure metal mono-oxides. On the basis of these results, we expect these alloy nanoparticles to have potential applications as electrodes in energy-generating devices such as Li-ion batteries. The higher Ni content (Mn0.19Ni0.81O) electrode exhibited a large reversible capacity (650 mAh g–1), a better initial efficiency (56%), and an improved rate and cycle performance, which was ascribed to higher electrical/electrolyte conductivity or improved surface film property. To our best knowledge, the reversible Li storage in metal oxides like MnO or NiO nanoparticles with about 10 nm diameter material itself has not been reported yet, indicative of the originality of the anode application of our materials. Also, we could expect a higher stability by addition of Mn into theconversion anode and reduction of material cost when compared with the very expensive Sn- or Mo-based oxide materials, electrolyte conductivity, or improved surface film property.

We report on the direct and facile method for noble metal/graphene nano-composites from graphite without reducing agents. In this system, the irradiant white-light instead of the chemical reducing agent exerts the influence on the synthesis of noble metal nanoparticles on graphene. Noble metal salts adsorbed on graphene flakes which were functionalized with ionic surfactants were reduced by irradiation with white light. In particular, noble metal nanoparticles were more evenly distributed on the surface of graphene which was functionalized with SDS than with CTAB.