Hao Shen Zhou

One-step synthesis of mesoporous PWA/SiO2 composite materials using triblock copolymer templates

Materials in the form of highly dispersed 12-phosphotungstic acid (PWA) in mesoporous SiO2 framework (PWA/meso-SiO2) have been synthesized by one-step condensation method. The samples were characterized by XRD, TEM, EDX, FE-SEM, FT-IR, 31P MAS NMR and N2 adsorption. The mesostructure of the materials obtained can be maintained up to the PWA loading amount of 30 wt%. The specific surface area and the pore size of the PWA/meso-SiO2 are 600 m2 g−1 and 8.9 nm, respectively, for 30 wt% PWA loading. PWA clusters preserved their Keggin ion structure and exist in the SiO2 framework with partial interactions between PWA and SiO2.

Development of Positive Electrode Materials for the High Rate Lithium Ion Battery by Nanostructure Control

Previously, we reported the fabrication of Na0.44MnO2 and LiMn2O4 single crystalline nanowire structure. Moreover, these electrodes showed good high rate property as lithium ion battery, because the nanostructure electrode is suitable for high rate lithium ion battery. Especially, the fabrication of LiMn2O4 single crystalline nanowire was very interesting results because the synthesis of 1-dimesional single crystal structure of LiMn2O4 is very difficult based on cubic crystal structure without anisotropic structure. The LiMn2O4 single crystalline nanowire was obtained thorough the self template method using Na0.44MnO2 nanowire. In this paper, we report the fabrication of Na0.44MnO2 and LiMn2O4 single crystalline nanowire structure and the property of lithium ion battery as review paper.

Electrochemical Properties of Blockcopolymer Templated Mesoporous Silicates with Heteropolyacids clusters

In this paper, we have studied a method of loading 12-tungstophosphoric acid (H 3 PW 12 O 40 ; PWA) into blockcopolymer templated (designated EO 20 PO 70 EO 20 ; Pluronic P-123) mesoporous SiO 2 framework without a disordering of mesostructure and without remarkable decrease of specific surface area through one-step condensation process. A precursor solution is initially prepared by TEOS (tetraethoxysilane) hydrolyzed with templating polymer (eg. triblock copolymer), and then mixed directly with PWA to condense mesoporous silicate products that incorporate PWA clusters in the framework. Heteropolyanions are possibly incorporated in the framework silicates. Electrochemical properties of these PWA impregnated mesoporous silicates were studied as electrode materials of Li ion battery as well as solid proton conductors.