Ⅰ. Introduction 1 II. Experimental 5 2.1 Chemicals and Materials 5 2.2 Synthesis of AgBiS2 Colloidal Nanocrystals 5 2.3 Fabrication of AgBiS2 Solar Cells 6 2.4 Device Characterization and Analysis 6 III. Result and discussions 8 3.1 Electron Transport Layer 8 3.1.1 Characterization of Engineered ETL 8 3.1.2 Measurement of Engineered Solar Cell Performance 16 3.2 Hole Transporting Layer 18 3.2.1 Characterization of Engineered HTL 18 3.2.2 Measurement of Engineered Solar Cell Performance 21 IV. Conclusion 23 Reference 30