Method for preparing monoclinic phase vanadium dioxide and doped nano powder thereof

The invention provides a method for preparing nano powder of monoclinic phase vanadium dioxide by using a hydrothermal-high temperature solid phase synthesis method. The method comprises the following steps of: a) reacting a vanadium source with a reducing agent to obtain vanadium dioxide (VO2)(B), VO2(A) or VO2 (paramontroseite) by using a hydrothermal method; b) washing the VO2(B), the VO2(A) or the VO2 (paramontroseite) and then thoroughly drying the VO2(B), the VO2(A) or the VO2 (paramontroseite) to form powder; c) vacuum-packaging the powder of the VO2(B), the VO2(A) or the VO2 (paramontroseite) in an airtight and high-temperature resistant container; and d) annealing the container at the temperature of between 350 and 1,200 DEG C for over 3 hours to obtain the nano powder of the monoclinic phase vanadium dioxide. The method has the characteristics of simple production technology, low production cost, environmental friendliness, higher product yield, higher product purity and easy industrial mass production.