Preparation method of porous black silicon material, preparation method of fluorescence sensor and method for detecting explosives by using fluorescence sensor

The invention discloses a preparation method of a porous black silicon material, a preparation method of a fluorescence sensor and a method for detecting explosives by using the fluorescence sensor. The preparation method comprises the following steps: blending isopropanol and deionized water, and adding soluble inorganic alkali into a mixed isopropanol solution; dissolving inorganic ferric nitrate in deionized water to prepare a ferric nitrate solution, adding hydrofluoric acid, and uniformly mixing to obtain an acid etching solution; immersing a clean silicon wafer into the alkali etching liquid, and obtaining an alkali etching silicon wafer after immersing and cleaning; immersing the alkali etching silicon wafer in the acid etching liquid, and obtaining the porous black silicon material after immersion and cleaning; etching the black silicon material into a pointed cone shape through an alkaline etching solution, and then performing surface modification through acid solution hydrothermal etching to obtain