溶胶-凝胶辅助水热法制备硼掺杂纳米VO2粉体

Synthesis of Boron-doped Monoclinic VO2 nanoparticles by sol-gel hydrothermal method

摘要:

采用溶胶-凝胶辅助水热法制备了硼掺杂纳米二氧化钒（VO2）粉体，探究了双氧水（H2O2）浓度、水热时间、退火温度、不同硼掺杂剂、硼掺杂量等工艺参数对合成硼掺杂纳米VO2(M)粉体的影响，并采用X-射线衍射仪（XRD）、X-射线光电子能谱分析仪（XPS）、电感耦合等离子体光谱仪（ICP）、场发射扫描电镜（SEM）、差示扫描量热仪（DSC）对硼掺杂纳米VO2粉体的结构、形貌和相变特性进行了表征。结果表明：H2O2浓度为15%，水热时间为72 h，退火温度为600 ℃，硼掺杂剂为硼酸、硼掺杂量≤10%为较优合成工艺条件；所制备出的硼掺杂纳米VO2粉体尺寸约为100 nm，形貌呈珊瑚状；硼原子成功替代了VO2(M)晶格中的钒原子，当实际掺杂量为0.6 at.%时，相变温度降低7.2 ℃。

Abstract:

Boron-doped vanadium dioxide (VO2) nanopowders were prepared by the sol-gel hydrothermal method. Effect of process parameters including the hydrogen peroxide (H2O2) concentration, hydrothermal time, annealing temperature, type of boron dopant and boron doping amount on the synthesis of boron-doped VO2 powders was investigated. The structure, morphology and phase transition properties of the boron-doped VO2 powders were characterized by the X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), field emission scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The results show that the superior synthesis process parameters are 15% for the H2O2 concentration, 72 h for the hydrothermal time, 600 °C for the annealing temperature, boric acid as the boron dopant, and less than 10 at.% for the boron doping amount. The obtained boron-doped VO2 powders have the size of around 100 nm with the morphology of coral-like structure. The boron atoms successfully replace the vanadium atoms in the VO2(M) lattice. The phase transition temperature is reduced by 7.2 °C, when the actual doping amount is 0.6 at.%.