Shen Yan, Xu Ningsheng, Deng Shaozhi, Zhang Yu, Liu Fei, Chen Jun
State Key Laboratory of Optoelectronic Materials and Technologies, Guangdong Province Key Laboratory of Display Material and Technology, and School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
Nanoscale. 2014 May 7;6(9):4659-68. doi: 10.1039/c3nr06811k.
A novel screw-like molybdenum nanostructure has been synthesized based on a simple thermal vapor deposition method. Each thread circle of the nanoscrews is formed by several crystalline Mo grains, which have a certain deflection with each other. The growth mechanism is described as a spiral growth mode, which depends heavily on the degree of supersaturation (σ) of deposited Mo vapors. The electrical property measurements and field emission properties on a single Mo nanoscrew show that their electrical conductivity should reach 3.44 × 10(4)-7.74 × 10(4) Ω(-1) cm(-1) and its maximum current should reach 15.8 μA. Mo nanoscrew film is also proved to have excellent field emission properties in different voltage driver modes. The largest emission current densities can reach 106.39 mA cm(-2) in the DC voltage driver mode and 0.66 A cm(-2) in the pulsed mode. A low turn-on field, good site distribution and remarkable emission stability is also recorded. These experimental results show that the highly conductive molybdenum nanoscrews should have potential applications as a cold cathode material for high current vacuum electron devices.
基于一种简单的热蒸发沉积方法合成了一种新型的螺旋状钼纳米结构。纳米螺旋的每个螺纹圈由几个结晶钼晶粒形成，这些晶粒相互之间有一定的偏转。其生长机制被描述为一种螺旋生长模式，这在很大程度上取决于沉积的钼蒸气的过饱和度(σ)。对单个钼纳米螺旋的电学性能测量和场发射性能表明，它们的电导率应达到3.44×10(4)-7.74×10(4)Ω(-1)cm(-1)，其最大电流应达到15.8μA。钼纳米螺旋膜在不同的电压驱动模式下也被证明具有优异的场发射性能。在直流电压驱动模式下，最大发射电流密度可达106.39mA cm(-2)，在脉冲模式下可达0.66A cm(-2)。还记录到了低开启场、良好的位点分布和显著的发射稳定性。这些实验结果表明，高导电性的钼纳米螺旋作为高电流真空电子器件的冷阴极材料应具有潜在的应用。
