We investigate diffusion behaviors of hydrogen(H),deuterium(D),and tritium(T) in bulk niobium(Nb) using first-principles method.The diffusion energy barrier with quantum-correction has been calculated to be 0.12 eV,wh...We investigate diffusion behaviors of hydrogen(H),deuterium(D),and tritium(T) in bulk niobium(Nb) using first-principles method.The diffusion energy barrier with quantum-correction has been calculated to be 0.12 eV,which is in good agreement with the experimental value of ～0.106 eV.According to diffusion theory presented by Wert and Zener,the diffusion pre-exponential factors of H,D,and T are shown to be 7.74×10-8m 2 s-1,5.47×10-8 m 2 s-1 and 4.48×10-8 m 2 s-1,respectively.These results are also in quantitative agreement with the corresponding experimental values.展开更多
We demonstrate a pH sensor based on ultrasensitive nanosize Schottky junctions formed within bottom-up grown dopant-flee arrays of assembled silicon nanowires. A new measurement concept relying on a continuous gate sw...We demonstrate a pH sensor based on ultrasensitive nanosize Schottky junctions formed within bottom-up grown dopant-flee arrays of assembled silicon nanowires. A new measurement concept relying on a continuous gate sweep is presented, which allows the straightforward determination of the point of maximum sensitivity of the device and allows sensing experiments to be performed in the optimum regime. Integration of devices into a portable fluidic system and an electrode isolation strategy affords a stable environment and enables long time robust FET sensing measurements in a liquid environment to be carried out. Investigations of the physical and chemical sensitivity of our devices at different pH values and a comparison with theoretical limits are also discussed. We believe that such a combination of nanofabrication and engineering advances makes this Schottky barrier-powered silicon nanowire lab-on-a-chip platform suitable for efficient biodetection and even for more complex biochemical analysis.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 51101135)
文摘We investigate diffusion behaviors of hydrogen(H),deuterium(D),and tritium(T) in bulk niobium(Nb) using first-principles method.The diffusion energy barrier with quantum-correction has been calculated to be 0.12 eV,which is in good agreement with the experimental value of ～0.106 eV.According to diffusion theory presented by Wert and Zener,the diffusion pre-exponential factors of H,D,and T are shown to be 7.74×10-8m 2 s-1,5.47×10-8 m 2 s-1 and 4.48×10-8 m 2 s-1,respectively.These results are also in quantitative agreement with the corresponding experimental values.
文摘We demonstrate a pH sensor based on ultrasensitive nanosize Schottky junctions formed within bottom-up grown dopant-flee arrays of assembled silicon nanowires. A new measurement concept relying on a continuous gate sweep is presented, which allows the straightforward determination of the point of maximum sensitivity of the device and allows sensing experiments to be performed in the optimum regime. Integration of devices into a portable fluidic system and an electrode isolation strategy affords a stable environment and enables long time robust FET sensing measurements in a liquid environment to be carried out. Investigations of the physical and chemical sensitivity of our devices at different pH values and a comparison with theoretical limits are also discussed. We believe that such a combination of nanofabrication and engineering advances makes this Schottky barrier-powered silicon nanowire lab-on-a-chip platform suitable for efficient biodetection and even for more complex biochemical analysis.
