NOVELTY - Preparation of black titanium dioxide nanotube involves dissolving ammonium molybdate in deionized water, magnetically stirring, adding analytical grade nitric acid, stirring, placing into 100 ml stainless steel autoclave with Teflon (RTM: PTFE) substrate, carrying out hydrothermal reaction, filtering, washing precipitate with deionized water, drying at room temperature to obtain molybdenum trioxide nanobelt, adding molybdenum trioxide nanobelt into deionized water, adding pure glycerin, magnetically stirring, carrying out hydrothermal reaction and filtering.    USE - Method for preparing black titanium dioxide nanotube (claimed) used in lithium ion battery, photocatalysis and solar cells.    ADVANTAGE - The method is simple and has low production cost.    DETAILED DESCRIPTION - Preparation of black titanium dioxide nanotube comprises dissolving 0.1 g ammonium molybdate in 30 ml deionized water, magnetically stirring, adding 6 ml analytical grade nitric acid, stirring for 0.5 hour, placing into 100 ml stainless steel autoclave with Teflon (RTM: PTFE) substrate, carrying out hydrothermal reaction at 180 degrees C for 24 hours, filtering, washing precipitate with deionized water for 3-6 times, drying at room temperature to obtain molybdenum trioxide nanobelt, adding 0.1-0.4 g molybdenum trioxide nanobelt into 10-30 ml deionized water, adding pure glycerin, magnetically stirring for 0.5-1 hour to obtain mixture A where volume ratio pure glycerin and deionized water is 0.5-1:1-2, adding 0.5-2 ml pure titanium tetrachloride to 0.1-0.5 ml analytically pure hydrazine hydrate, magnetically stirring for 0.5-1 hour to obtain mixed solution B, adding mixed solution B to mixture A, stirring, placing into 100 ml stainless steel autoclave with Teflon (RTM: PTFE) substrate, carrying out hydrothermal reaction at 140-230 degrees C for 12-16 hours, filtering, washing precipitate with anhydrous ethanol for 3-6 times and drying to obtain nanotubes with length of 1-10 mu m, diameter of 300-500 nm and thickness of 10-20 nm.