The invention relates to a preparation method of a
niobium (V)
pentoxide urchin-like nano sphere and an application of the nano sphere as a photocatalyst. The preparation method comprises the following steps: step one, weighing
alcohol and deionized water according to a volume ratio of 20:1 to 1:100 at a
room temperature, mixing water and
alcohol, and stirring to prepare an
alcohol solution; step two, weighing soluble
niobium salt, dissolving the soluble
niobium salt into the alcohol solution obtained in the step one, and stirring for 0.5 to 5 hours to obtain a transparent solution; step three, transferring the obtained transparent solution to a hydrothermal reactor, wherein the transparent solution accounts for 50 to 70% of the total volume of the reactor, and the hydrothermal reactions are performed at a temperature of 100 to 220 DEG C, after reactions, naturally cooling the reactor to the
room temperature, and washing and
drying the reaction products to obtain the niobium (V)
pentoxide urchin-like nano spheres. According to the preparation method, alcohol is used to adjust the polarity of the solution so as to adjust the
growth speed of niobium, and thus niobium (V)
pentoxide urchin-like nano spheres, which have uniform morphology and controllable diameters, are obtained. The prepared niobium (V) pentoxide urchin-like nano spheres has a high catalytic activity on degrading dyes in water in the presence of visible light.