Method for preventing oxidative degradation of black phosphorus nanosheet and application of black phosphorus nanosheet

[0051] Example 1

[0052] 1. Preparation of black phosphorus nanosheets

[0053] Black phosphorus nanosheets: Add 100 mg of black phosphorus powder to 1000 ml of N-methylpyrrolidone solvent, use a cell crusher to perform ultrasonic peeling for 6-10 hours, and centrifuge the obtained black phosphorus nanosheet suspension (6000 r/min) for 10 minutes, collect the supernatant, then centrifuge (10,000 r/min) for 20 minutes, collect the solid, and finally wash with ethanol 5 times to remove N-methylpyrrolidone After that, it was put into a vacuum oven at 40° C. for 12 hours to obtain black phosphorus nanosheets.

[0054] Hydrogenated black phosphorus nanosheets: 20 mg of black phosphorus nanosheet powder was transferred into a tube furnace under a mixed atmosphere of argon and hydrogen (argon flow rate: 50 mL/min, hydrogen flow rate: 5 mL/min) from room temperature The temperature was raised to 350°C at 5°C/min, and then kept for 4 hours; after the reaction was completed, it was naturally cooled to room temperature, and the transmission electron microscope photo was as follows. figure 1 As shown in (b), the spherical aberration electron microscope photo is as follows figure 2 (b), the infrared spectrum is shown in image 3 (b), the Raman shift spectrum is shown in Figure 4 (b), the Raman image is shown in Figure 5 (b). The hydrogenated black phosphorus nanosheets contain 5-10% molar ratio of P-H covalent bonds through elemental analysis.

[0055] 2. Stability test

[0056] The stability of the hydrogenated black phosphorus nanosheets was tested in two environments. One was in the water environment, under natural light, and the temperature was 25±5°C; Humidity is 80±10%. The stability test in the water environment is specifically as follows: preparing a suspension of hydrogenated black phosphorus nanosheets with a concentration of 25 mg/L, and at a set time point, tracking and testing the concentration of hydrogenated black phosphorus nanosheets with a UV-Vis spectrophotometer, obtaining Degradation and absorption curves of photocatalyst hydrogenated black phosphorus nanosheets in aqueous environment, such as Image 6 (b). The stability test in the atmospheric environment is as follows: apply the hydrogenated black phosphorus nanosheet suspension droplets to the mica sheet, quickly dry in a vacuum environment, and at a set time point, use an atomic force microscope to track and test the morphology and thickness of the nanosheets changes, such as Figure 8 where, (a) shows the morphological evolution of hydrogenated black phosphorus nanosheets in atmospheric environment for 2 hours, (b) shows the morphological evolution of hydrogenated black phosphorus nanosheets in atmospheric environment for 7 days, ( c) Picture showing the morphology evolution of hydrogenated black phosphorus nanosheets in atmospheric environment for 15 days.

[0057] 3. Hydrogen production stability test

[0058] 5 mg of the above hydrogenated black phosphorus nanosheets were added to a reaction tube with magnetons, and a mixed solvent of methanol and water (V alcohol:V water=1:5) and 0.5 mg of cobalt chloride were injected. After evacuating the air with an inert gas (nitrogen or argon, etc.), the reaction tube was irradiated with a blue LED lamp for 8 hours, and the system was cooled by water cooling.

[0059]Hydrogen production stability test of hydrogenated black phosphorus nanosheets as photocatalyst: After the above reaction, the product hydrogen was quantified by gas chromatography equipped with a thermal conductivity detector. The hydrogenated black phosphorus nanosheets can be collected by centrifugation as the photocatalyst for the next experiment. This test is cycled 10 times. The test results are as follows Figure 10 shown.