Hydrogen storage properties of Mg-TiO_2 composite powder prepared by arc plasma method

Mg-based Mg-TiO2 composite powder was prepared by arc plasma evaporation of the Mg＋5%TiO2 mixture followed by passivation in air. ICP, XRD and SEM techniques were used to characterize the composition, phase components and microstructure of the composite powder. The hydrogen sorption properties of the composite powder were investigated by DSC and PCT techniques. According to the data from PCT measurements, the hydrogenation enthalpy and entropy changes of the composite powder are calculated to be-71.5 kJ/mol and-130.1 J/（K·mol）, respectively. Besides, the hydrogenation activation energy is determined to be 77.2 kJ/ mol. The results indicate that TiO2 added into Mg by arc plasma method can act as a catalyst to improve the hydrogen sorption kinetic properties of Mg.

Mode transition in dusty micro-plasma driven by pulsed radio-frequency source in C_2H_2/Ar mixture

Physical qualities of dusty plasma in the pulsed radio-frequency C_2H_2/Ar microdischarges are carefully investigated by a one-dimensional hydrodynamic model and aerosol dynamics model.Since the thermophoretic force has a great effect on the nanoparticle density spatial distribution,the neutral gas energy equation is taken into accounted.The effects of pulse parameters（dust ratio,modulation frequency） on the nanoparticle formation and growth process are mainly discussed.The calculation results show that,as the duty ratio increases,the mode transition from the sheath oscillation（a regime） to the secondary electron heating（7 regime） occurred,which is quite different from the conventional pulsed discharge.Moreover,the effect of modulation frequency on the width of sheath and plasma density is analyzed.Compared with the H_2CC^-ions,the modulation frequency effect on the nanoparticles density becomes more prominent.

Acetylene/argon mixture plasma to build ultrathin carbon bridge of CF_(x)/C/MnO_(2) for high-rate lithium primary battery

Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe electrochemical polarization in lithium/fluorinated carbon primary batteries(Li/CF_(x))remains a considerable challenge for achieving batteries with excellent rate capability.Herein,CFxwas modified by using acetylene/argon mixture plasma combined with MnO_(2)particles.The CF_(x)/C/MnO_(2)composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CF_(x).The excellent rate performance of CF_(x)/C/MnO_(2)was due to the high electrochemical activity provided by the atomicscale conductive carbon layer and ultrafine MnO_(2)particles.Compared with pristine CF_(x),the charge transfer resistance of the optimized CF_(x)/C/MnO_(2)decreased from 218.5 to 48.2Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g^(-1),The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CF_(x)discharge,and the high electrochemical activity of the ultrafine MnO_(2)particles provided a faster lithium-ion diffusion rate.

直流电弧等离子体法制备 TiO_2 纳米超细粉

采用直流电弧等离子体法直接制备了晶态的ＴｉＯ２纳米超细粉，粉体中的晶粒既有锐钛矿结构，也有金红石结构；既有单晶结构的ＴｉＯ２，也有多晶结构的ＴｉＯ２。当热处理温度低于６００℃时，粉体颗粒的长大较为缓慢，粒径在２０ｎｍ以下；温度高于７００℃时，颗粒迅速长大，锐钛矿向金红石结构的转变明显；当温度达到８００℃时，样品转变为单晶结构的金红石型ＴｉＯ２，颗粒大小在４０—１２０ｎｍ之间。

氢电弧等离子体法制备纳米钛粒子脱硫性能研究

使用H2+Ar等离子体法制备纳米Ti粒子并用球磨法负载到载体上,500℃焙烧后制成纳米TiO2脱硫催化剂.利用TEM、BET、XRD等手段,对催化剂进行了表征.焙烧后纳米钛粒子主要以金红石型TiO2存在.在不同温度、空速、SO2/CS2和老化条件下,进行CS2的水解实验证明,物理法制备的纳米TiO2/Al2O3催化剂具有较高的耐硫酸盐化中毒能力.