Molybdenum nitride(Mo-N) modified layer on Ti6Al4V alloy was obtained by the plasma surface alloying technique. The bacteria adherence property of the Mo-N modified layer on Ti6Al4V alloy on the oral bacteria Streptoc...Molybdenum nitride(Mo-N) modified layer on Ti6Al4V alloy was obtained by the plasma surface alloying technique. The bacteria adherence property of the Mo-N modified layer on Ti6Al4V alloy on the oral bacteria Streptococcus Mutans was investigated and compared with that of Ti6Al4V alloy by fluorescence microscopy. The mechanism of the bacteria adherence was discussed. The sample was characterized by X-ray diffractometry(XRD),X-ray photoelectron spectroscopy(XPS) and rough-meter. The results show that the Mo-N modified layer is composed of phase Mo2N(fcc) and Mo2N(tetr). There are Mo 3d,N 1s,C 1s and O 1s in the Mo-N modified layer Ti 2p,O 1s,C 1s,in the Ti6Al4V alloy. The surface roughness(Ra) of Ti6Al4V alloy and the Mo-N modified layer is(0.06±0.01) μm and(0.16±0.01) μm,respectively. The Mo-N modified layer inhibits the bacteria adherence. Mo and N on surface of modified layer play a vital role in inhibiting the bacteria adherence.展开更多
以F127为模板剂,Ni Cl2为镍源,尿素为氮源,间苯二酚甲醛原位聚合树脂为碳源,分别采用均相法和两相法制备Ni-NOMC-1,Ni-N-OMC-2纳米复合材料。X射线衍射(XRD)、激光拉曼以及透射电子显微镜(TEM)等测试结果表明,复合材料具有有序介孔结构...以F127为模板剂,Ni Cl2为镍源,尿素为氮源,间苯二酚甲醛原位聚合树脂为碳源,分别采用均相法和两相法制备Ni-NOMC-1,Ni-N-OMC-2纳米复合材料。X射线衍射(XRD)、激光拉曼以及透射电子显微镜(TEM)等测试结果表明,复合材料具有有序介孔结构,Ni以金属微粒形式嵌于碳骨架中,提高了有序介孔碳的石墨化程度。X射线光电子能谱测试(XPS)表明尿素热解后以4种形式存在:sp3杂化与C结合的N原子,吡啶N原子,sp2杂化与C结合的N原子以及quaternary-N原子。Ni-N的共改性改变了碳载体的理化性质,有利于Pt纳米粒子的负载与分散。均相法制备的Ni-N-OMC-1复合材料微波负载Pt后,氧还原极限电流密度为5.32 m A·cm-2,氢氧化电化学活性面积高达138.53 m2·g-1,电化学催化活性优于商业20%Pt/C材料(4.49 m A·cm-2,96.98 m2·g-1)。展开更多
Graphene-like, ternary system B-C-N atomic layer materials promise highly tunable electronic properties and a plethora of potential applications. However, thus far, experimental synthesis of the B-C-N atomic layers no...Graphene-like, ternary system B-C-N atomic layer materials promise highly tunable electronic properties and a plethora of potential applications. However, thus far, experimental synthesis of the B-C-N atomic layers normally yields a microscopic phase-segregated structure consisting of pure C and BN domains. Further, growing the truly ternary B-C-N phase layers with homogenous atomic arrangements has proven to be very challenging. Here, in designing a better- controlled process for the chemical vapor deposition （CVD） growth of B-C-N atomic layer films with the minimized C and BN phase segregation, we selected trimethyl borane （TMB）, a gaseous organoboron compound with pre-existing B--C bonds, as the molecular precursor to react with ammonia （NH3） gas that serves as the nitrification agent. The use of this unique B-C delivery precursor allows for the successful synthesis of high-quality and large-area B-C-N atomic layer films. Moreover, the TMB/NH3 reactant combination can offer a high level of tunability and control of the overall chemical composition of B-C-N atomic layers by regulating the relative partial pressure of two gaseous reactants. Electrical transport measurements show that a finite energy gap can be opened in the as-grown B-C-N atomic layers and its tunability is essentially dependent on the relative C to BN atomic compositions. On the basis of carefully controlled experiments, we show that the pre-existing B-C bonds in the TMB molecular precursor have played a crucial role in effectively reducing the C and BN phase segregation problem, thereby facilitating the formation of truly ternary B-C-N phase atomic layers.展开更多
基金Project(50501016) supported by the National Natural Science Foundation of Chinaproject(2007AAO3Z521) supported by the National High-tech Research and Development program+1 种基金Projects (20051049, 2006021023) supported by the Natural Science Foundation of Shanxi Province, ChinaProject(2006-27) supported by the Foundation for Young Subjects Leaders in University of Shanxi and Scientific Foundation for Returned Overseas Scholars of Shanxi Province, China
文摘Molybdenum nitride(Mo-N) modified layer on Ti6Al4V alloy was obtained by the plasma surface alloying technique. The bacteria adherence property of the Mo-N modified layer on Ti6Al4V alloy on the oral bacteria Streptococcus Mutans was investigated and compared with that of Ti6Al4V alloy by fluorescence microscopy. The mechanism of the bacteria adherence was discussed. The sample was characterized by X-ray diffractometry(XRD),X-ray photoelectron spectroscopy(XPS) and rough-meter. The results show that the Mo-N modified layer is composed of phase Mo2N(fcc) and Mo2N(tetr). There are Mo 3d,N 1s,C 1s and O 1s in the Mo-N modified layer Ti 2p,O 1s,C 1s,in the Ti6Al4V alloy. The surface roughness(Ra) of Ti6Al4V alloy and the Mo-N modified layer is(0.06±0.01) μm and(0.16±0.01) μm,respectively. The Mo-N modified layer inhibits the bacteria adherence. Mo and N on surface of modified layer play a vital role in inhibiting the bacteria adherence.
文摘以F127为模板剂,Ni Cl2为镍源,尿素为氮源,间苯二酚甲醛原位聚合树脂为碳源,分别采用均相法和两相法制备Ni-NOMC-1,Ni-N-OMC-2纳米复合材料。X射线衍射(XRD)、激光拉曼以及透射电子显微镜(TEM)等测试结果表明,复合材料具有有序介孔结构,Ni以金属微粒形式嵌于碳骨架中,提高了有序介孔碳的石墨化程度。X射线光电子能谱测试(XPS)表明尿素热解后以4种形式存在:sp3杂化与C结合的N原子,吡啶N原子,sp2杂化与C结合的N原子以及quaternary-N原子。Ni-N的共改性改变了碳载体的理化性质,有利于Pt纳米粒子的负载与分散。均相法制备的Ni-N-OMC-1复合材料微波负载Pt后,氧还原极限电流密度为5.32 m A·cm-2,氢氧化电化学活性面积高达138.53 m2·g-1,电化学催化活性优于商业20%Pt/C材料(4.49 m A·cm-2,96.98 m2·g-1)。
基金Acknowledgements We acknowledge financial support from the National Natural Science Foundation of China （Nos. 21322304 and 51472267） and the National Basic Research Program of China （Nos. 2012CB933003 and 2013CB932603） and the Strategic Priority Research Program B of the Chinese Academy of Sciences （No. XDB07030100） of China.
文摘Graphene-like, ternary system B-C-N atomic layer materials promise highly tunable electronic properties and a plethora of potential applications. However, thus far, experimental synthesis of the B-C-N atomic layers normally yields a microscopic phase-segregated structure consisting of pure C and BN domains. Further, growing the truly ternary B-C-N phase layers with homogenous atomic arrangements has proven to be very challenging. Here, in designing a better- controlled process for the chemical vapor deposition （CVD） growth of B-C-N atomic layer films with the minimized C and BN phase segregation, we selected trimethyl borane （TMB）, a gaseous organoboron compound with pre-existing B--C bonds, as the molecular precursor to react with ammonia （NH3） gas that serves as the nitrification agent. The use of this unique B-C delivery precursor allows for the successful synthesis of high-quality and large-area B-C-N atomic layer films. Moreover, the TMB/NH3 reactant combination can offer a high level of tunability and control of the overall chemical composition of B-C-N atomic layers by regulating the relative partial pressure of two gaseous reactants. Electrical transport measurements show that a finite energy gap can be opened in the as-grown B-C-N atomic layers and its tunability is essentially dependent on the relative C to BN atomic compositions. On the basis of carefully controlled experiments, we show that the pre-existing B-C bonds in the TMB molecular precursor have played a crucial role in effectively reducing the C and BN phase segregation problem, thereby facilitating the formation of truly ternary B-C-N phase atomic layers.
