Method for preparing nitrogen-doped bismuth tungstate powder photocatalyst through microwave hydrothermal method

The invention provides a method for preparing a nitrogen-doped bismuth tungstate powder photocatalyst through a microwave hydrothermal method. The method comprises the following steps of: adding de-ionized water into bismuth nitrate pentahydrate and sodium tungstate dihydrate serving as raw materials and urea serving as an N source, stirring to uniformly mix the raw materials, stopping the stirring and producing white precipitate; placing in an ultrasonic instrument to perform ultrasonic treatment for 10-30 minutes; performing complete precipitation reaction to obtain precursor of microwave hydrothermal reaction; transferring the precursor into a reaction kettle; reacting by using the microwave hydrothermal method for 30-90 minutes at 160-200 DEG C; and taking out of the reaction kettle, collecting the precipitate, cleaning and drying. The method has the advantages of low reaction temperature of about 180 DEG C and short reaction time of probability 50-60 minutes; and the prepared powder has high reaction activity and low energy consumption and is environmentally-friendly.