Co3O4 nanoparticles have been prepared by a facile strategy, which involves the thermal decomposition of nanoparticles of cobalt-based Prussian blue analogues at different temperatures. The nanoparticles prepared at 450, 550, 650, 750, and 850 °C exhibited a high discharge capacity of 800, 970, 828, 854, and 651 mAhg–1, respectively, after 30 cycles at a current density of 50 mAg–1. The nanocages produced at 550 °C show the highest lithium storage capacity. It is found that the nanocages display nanosize grains, hollow structure, a porous shell, and large specific surface area. At the temperature higher than 650 °C, the samples with larger grains, better crystallinity, and lower specific surface area can be obtained. It is found that the size, crystallinity, and morphology of nanoparticles have different effects on electrochemical performance. Better crystallinity is able to enhance the initial discharge capacity, while porous structure can reduce the irreversible loss. Therefore, the optimal size, crystallinity, and cage morphology are suggested to be responsible for the improved lithium storage capacity of the sample prepared at 550 °C. The as-prepared Co3O4 nanoparticles also have a potential application as anode material for Li-ion batteries due to their simple synthesis method and large capacity.

Herein we report a novel facile strategy for the fabrication of Co(3)O(4) porous nanocages based on the Kirkendall effect, which involves the thermal decomposition of Prussian blue analogue (PBA) Co(3)[Co(CN)(6)](2) truncated nanocubes at 400 °C. Owing to the volume loss and release of internally generated CO(2) and N(x) O(y) in the process of interdiffusion, Co(3)O(4) nanocages with porous shells and containing nanoparticles were finally obtained. When evaluated as electrode materials for lithium-ion batteries, the as-prepared Co(3)O(4) porous nanocages displayed superior battery performance. Most importantly, capacities of up to 1465 mA h g(-1) are attained after 50 cycles at a current density of 300 mA g(-1). Moreover, this simple synthetic strategy is potentially competitive for scaling-up industrial production.

Herein, based on the recently developed magnetic-induced self-assembly techniques, we designed a novel, simple and low-cost method to fabricate a special class of photonic crystals with double photonic band-gap hetero-structures, and eventually achieved the purpose of modulating the optical diffraction color of the structural colors. The method greatly simplifies the fabrication of photonic crystals with multiple photonic band-gap hetero-structures and extends the modulation means of the optical diffraction color of structural colors. Furthermore, it is worth noting that due to the resulting structural colors that are derived from the double photonic band-gap hetero-structures consisting of double diffraction peaks and presenting a magnetic switching effect through the application and withdrawal of the magnetic fields (0.05 T), which is more difficult to be imitated by those of chemical dyes and pigments, a kind of novel photonic anti-counterfeiting label has been prepared with these structural colors. Due to the widespread counterfeiting of various commercial objects and the urgent requirements of forgery protection, the photonic anti-counterfeiting label demonstrated in our work will undoubtedly find applications in meeting the growing anticounterfeiting needs.

Bulk metals and metal chalcogenides are found to dissolve in primary amine-dithiol solvent mixtures at ambient conditions. Thin-films of CuS, SnS, ZnS, Cu2Sn(S(x),Se(1-x))3, and Cu2ZnSn(S(x)Se(1-x))4 (0 ≤ x ≤ 1) were deposited using the as-dissolved solutions. Cu2ZnSn(S(x)Se(1-x))4 solar cells with efficiencies of 6.84% and 7.02% under AM1.5 illumination were fabricated from two example solution precursors, respectively.

In this paper, a potential strategy for increasing the hydrogen sorption has been demonstrated by using the nanostructure of metal organic framework. Prussian Blue analogue (PBA) Cd 3 [Co(CN) 6 ] 2 •nH 2 O nanocubes and octahedrons were successfully obtained at room temperature in the presence of poly(vinylpyrrolidone) (PVP) and sodium dodecylbenzenesulfonate (SDBS), respectively. The as-prepared products were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and thermogravimetric analysis (TGA). Detailed proof indicated that the synthetic parameters such as surfactant, the ratio of different solvents (water and ethanol) play crucial roles in the morphology and size of the nanoparticles. The fine-detailed information about porous structures of the samples has also been studied using the Brunauer−Emmet−Teller isotherm. Most importantly, two kinds of nanostructures both display high adsorption on H 2 and CO 2 , showing enhanced adsorption properties compared with the bulk materials. To our knowledge, this is the first report on the synthesis of Cd 3 [Co(CN) 6 ] 2 nanomaterials and their H 2 , CO 2 adsorption applications at the nanoscale.

No abstract

This communication describes carboxyl-functionalized nanochains with amorphous carbon shell (18 nm) and magnetic core using ferrocene as a single reactant under the induction of an external magnetic field (0.40 T), which shows a superparamagnetic behavior and magnetization saturation of 38.6 emu g(-1). Because of mesoporous structure (3.8 nm) and surface negative charge (-35.18 mV), the nanochains can be used as adsorbent for removing the heavy metal ions (90%) from aqueous solution.

No abstract