Fig. 1. Crystal structures of black phosphorus. (a) Side view; (b) side view of single layer black phosphorus; (c) top view of single layer black phosphorus

Fig. 2. Optical images of black phosphorus before and after Ar+ plasma etching. (a) Before etching; (b) after etching

Fig. 3. Preparation of two-dimensional black phosphorus by electrochemical method

Fig. 4. Preparation of black phosphorus quantum dots by probe ultrasonic combined with ice bath ultrasonic

Fig. 5. Preparation of black phosphorus quantum dots by solvothermal method

Fig. 6. Preparation of black phosphorus quantum dots by shearing method

Fig. 7. Diagram of chemical vapor deposition. (a) Preparation of red phosphorus film; (b) preparation of black phosphorus film

Fig. 8. BN-BP-BN interlayer heterogeneous section. (a) Preparation process diagram; (b) device structural diagram; (c) O2-plasma etching; (d) optical image of device

Fig. 9. Preparation route of two kinds of heterojunction

Fig. 10. Solar cell based on BP/PCBM heterojunction. (a) Structural diagram; (b) energy level structure diagram

Fig. 11. Quasi-solid double-sided N-type dye-sensitized solar cell. (a) Structural diagram; (b) energy level diagram

Fig. 12. Two kinds of organic solar cells. (a) Diagram of solar cell; (b) J-V characteristic curve of conventional structure; (c) J-V characteristic curve of inverted structure

Fig. 13. Synthesis diagram of black phosphorus/perovskite hybrid structure

Fig. 14. Structural diagram of hybrid perovskite solar cells