利用对氧缺陷的TiO_2-B材料进行密度泛函理论的计算,阐述了氧空穴对于TiO_2-B材料的电化学性质的影响。计算研究主要聚焦于缺陷材料的锂离子迁移和电子导电性等基本问题。计算结果表明在低锂离子浓度下(x(Li/Ti)≤0.25),相比于无缺陷的T...利用对氧缺陷的TiO_2-B材料进行密度泛函理论的计算,阐述了氧空穴对于TiO_2-B材料的电化学性质的影响。计算研究主要聚焦于缺陷材料的锂离子迁移和电子导电性等基本问题。计算结果表明在低锂离子浓度下(x(Li/Ti)≤0.25),相比于无缺陷的TiO_2-B,氧缺陷TiO_2-B有着更高的插入电压和更低的b轴方向迁移活化能,意味着锂离子的嵌入也更容易,这对于可充电电池的充电过程是有利的。而在高浓度下(x(Li/Ti)=1),锂饱和的氧缺陷TiO_2-B相较于无缺陷的TiO_2-B有着较低的插入电压,更有利于锂离子的脱嵌过程,这对于可充电电池的放电过程也是有利的。电子结构计算表明缺陷材料的禁带宽度在1.0-2.0 e V之间,低于无缺陷的材料的3.0 e V。主要态密度贡献者是Ti-Ov-3d,并且随着氧空穴的增加它的强度也变得更强。这就表明氧缺陷TiO_2-B有更好的电子导电性。展开更多
采用均匀沉淀法,以硫酸钛为前躯体,制备TiO_2-Bi_2O_3复合粉体材料。以罗丹明B为目标降解物,研究了热处理温度、催化剂用量对该复合材料光催化性能的影响。光催化活性随焙烧温度升高而增大,550℃焙烧的样品光催化活性高。当催化剂用量为...采用均匀沉淀法,以硫酸钛为前躯体,制备TiO_2-Bi_2O_3复合粉体材料。以罗丹明B为目标降解物,研究了热处理温度、催化剂用量对该复合材料光催化性能的影响。光催化活性随焙烧温度升高而增大,550℃焙烧的样品光催化活性高。当催化剂用量为0.026g/10 m L时,20 mg/L的罗丹明B溶液在紫外光照射100 min后,降解率可达到90%。该复合物对罗丹明B溶液的光催化降解符合一级动力学方程。展开更多
Mesoporous TiO_2-B/anatase microparticles have been in-situ synthesized from K_2Ti_2O_5 without template.The TiO_2-B phase around the particle surface accelerates the diffusion of charges through the interface,while t...Mesoporous TiO_2-B/anatase microparticles have been in-situ synthesized from K_2Ti_2O_5 without template.The TiO_2-B phase around the particle surface accelerates the diffusion of charges through the interface,while the anatase phase in the core maintains the capacity stability.The heterojunction interface between the main polymorph of anatase and the trace of TiO_2-B exhibits promising lithium ion battery performance.This trace of 5%(by mass) TiO_2-B determined by Raman spectra brings the first discharge capacity of this material to 247 mA · h ·g^(-1),giving 20%improvement compared to the anatase counterpart Stability testing at 1 C reveals that the capacity maintains at 171 mA·h·^(-1),which is better than 162 mA·h·g^(-1) for single phase anatase or 159 mA·h·g^(-1) for TiO_2-B.The mesoporous TiO_2-B/anatase rnicroparticles also show superior rate performance with 100 mA·h·g^(-1) at 40 C,increased by nearly 25%as compared to pure anatase.This opens a possibility of a general design route,which can be applied to other metal oxide electrode materials for rechargeable batteries and supercapacitors.展开更多
A supported Ni-B/TiO2 amorphous catalyst was prepared by impregnation and reduction. It was characterized by XRD, SAED, DSC, XPS, etc.. The catalytic activity of catalyst was measured through the hydrogenation of he...A supported Ni-B/TiO2 amorphous catalyst was prepared by impregnation and reduction. It was characterized by XRD, SAED, DSC, XPS, etc.. The catalytic activity of catalyst was measured through the hydrogenation of heavy arenes in petrochemicals for the first time.展开更多
基金supported by the State Key Program of Natural Science Foundation of Tianjin,China(13JCZDJC26800)Foundation of State Key Laboratory of Coal Conversion,China(J15-16-908)Natural Science Foundation of Shanxi Province,China(2013011012-8)~~
文摘利用对氧缺陷的TiO_2-B材料进行密度泛函理论的计算,阐述了氧空穴对于TiO_2-B材料的电化学性质的影响。计算研究主要聚焦于缺陷材料的锂离子迁移和电子导电性等基本问题。计算结果表明在低锂离子浓度下(x(Li/Ti)≤0.25),相比于无缺陷的TiO_2-B,氧缺陷TiO_2-B有着更高的插入电压和更低的b轴方向迁移活化能,意味着锂离子的嵌入也更容易,这对于可充电电池的充电过程是有利的。而在高浓度下(x(Li/Ti)=1),锂饱和的氧缺陷TiO_2-B相较于无缺陷的TiO_2-B有着较低的插入电压,更有利于锂离子的脱嵌过程,这对于可充电电池的放电过程也是有利的。电子结构计算表明缺陷材料的禁带宽度在1.0-2.0 e V之间,低于无缺陷的材料的3.0 e V。主要态密度贡献者是Ti-Ov-3d,并且随着氧空穴的增加它的强度也变得更强。这就表明氧缺陷TiO_2-B有更好的电子导电性。
文摘采用均匀沉淀法,以硫酸钛为前躯体,制备TiO_2-Bi_2O_3复合粉体材料。以罗丹明B为目标降解物,研究了热处理温度、催化剂用量对该复合材料光催化性能的影响。光催化活性随焙烧温度升高而增大,550℃焙烧的样品光催化活性高。当催化剂用量为0.026g/10 m L时,20 mg/L的罗丹明B溶液在紫外光照射100 min后,降解率可达到90%。该复合物对罗丹明B溶液的光催化降解符合一级动力学方程。
基金This work was supported by the National Natural Science Foundation of China （No. 51102134）, the Natural Science Foundation of Jiangsu Province （No. BK20131349）, the China Postdoctoral Science Foundation （No. 2013M530258）, and the Jiangsu Planned Projects for Postdoctoral Research Funds （No. 1202001B）.
基金Supported by the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT 0732)the National Natural Science Foundation of China(21136004,20736002,21176113,20876073)+2 种基金NSFC-RGC(20731160614)China Postdoctoral Science Foundation(20110491407)the National Basic Research Program of China(2009CB623407,2009CB219902 and 2009CB226103)
文摘Mesoporous TiO_2-B/anatase microparticles have been in-situ synthesized from K_2Ti_2O_5 without template.The TiO_2-B phase around the particle surface accelerates the diffusion of charges through the interface,while the anatase phase in the core maintains the capacity stability.The heterojunction interface between the main polymorph of anatase and the trace of TiO_2-B exhibits promising lithium ion battery performance.This trace of 5%(by mass) TiO_2-B determined by Raman spectra brings the first discharge capacity of this material to 247 mA · h ·g^(-1),giving 20%improvement compared to the anatase counterpart Stability testing at 1 C reveals that the capacity maintains at 171 mA·h·^(-1),which is better than 162 mA·h·g^(-1) for single phase anatase or 159 mA·h·g^(-1) for TiO_2-B.The mesoporous TiO_2-B/anatase rnicroparticles also show superior rate performance with 100 mA·h·g^(-1) at 40 C,increased by nearly 25%as compared to pure anatase.This opens a possibility of a general design route,which can be applied to other metal oxide electrode materials for rechargeable batteries and supercapacitors.
基金the NNSFC, RFDP, NSFTC and NNSFCTJ for the financial support (20003006, 2000005520, 99380171 and 031606211).
文摘A supported Ni-B/TiO2 amorphous catalyst was prepared by impregnation and reduction. It was characterized by XRD, SAED, DSC, XPS, etc.. The catalytic activity of catalyst was measured through the hydrogenation of heavy arenes in petrochemicals for the first time.
