Collection of Solar Cells
In recent years, perovskite materials become a research hotspot in the field of solar cells due to their excellent photovoltaic properties, but control of their interface defects still remains one of the key problems to be solved. In this study, an organic small molecule additive (L-3-(4-pyridyl)-alanine (PLA)) was introduced in the preparation of perovskite photoabsorption layer by two-step solution method. The characterizations showed that the introduction of PLA could comprehensively improve photoelectric performance of the device, with optimal energy conversion efficiency of 21.53%, in contrast to that of the reference device (20.10%). Further studies showed that PLA could reduce the trap state density of the device from 5.59×1016cm-3 to 3.40×1016cm-3, promote the interface charge extraction, and decrease the carrier recombination. The above improvements can be attributed to the PLA induced PbI2 enrichment at grain boundaries and PLA anchoring at defects, which play an important roles in passivate defects. This study can provide guideline for further regulating the defects of perovskite solar cells.
In the production process of multicrystalline silicon solar cells, diamond wire sawn (DWS) cutting technology attracts wide attention because of its advantages of high cutting speed, high precision and less loss of raw materials. But the traditional acid etching technology cannot match the shallow damage layer formed on the surface of diamond wire sawn cut multicrystalline silicon wafer to make the texture surface. On the contrary, the metal-catalyzed chemical etching method owns the advantages of simple operation, controllable structure and easy to form the structure with high aspect ratio, indicating a wide range of application on diamond wire sawn cut multicrystalline silicon wafer. This paper systematically summarizes the work of the etching mechanisms and the structures of textures by different metal catalysts in the process of making texture surface, and deeply discusses the single and composite catalytic etching process of Ag and Cu, the structure of texture surface, and the performance of solar cells. Finally, the problems of metal-catalyzed chemical etching on the surface of diamond wire sawn cut multicrystalline silicon are analyzed, and their future research directions are prospected.
Electron transport layer is a key part for perovskite solar cell (PSC), which can block holes and transmit electrons to reduce recombination. In this study, SnO2 was synthesized with low-temperature solution-processed method and used as electronic transport layer for perovskite solar cells. The influence of annealing temperature on the properties of SnO2 films and PSCs were systematically studied. The results showed that with the annealing temperatures at 60, 90, 120, 240 ℃, the surfaces of SnO2 films own more pores; while annealed at 150, 180, 210 ℃, the corresponding surfaces show fewer pores. It was found that the transmittance of FTO glass covered with SnO2 films is better than that of the bare FTO glass. With SnO2 annealed at 180 ℃, the electron mobility of the thin film is the highest. The corresponding PSC possesses the best transmission resistance, composite resistance, and superior photovoltaic performance. The photoelectric conversion efficiency, the open-circuit voltage, the short-circuit current and the filling factor were 17.28%, 1.09 V, 20.91 mA/cm2 and 75.91%, respectively.
As smart electronic products are increasingly applied in our daily life, there is not only an increasing demand for high-performance photovoltaic power generation devices, but also strong need for in-situ energy storage functions in these devices. The integration of energy generating components and energy storage components into one device has become an attractive challenging technology. The basic idea is that by integration design and engineering the assembly of the photoelectric conversion layer and the energy storage layer into one in-situ energy conversion and storage system could not only offer multiple functions, such as self-powered ability, weak light buffer and portability, but reduce sunlight fluctuation effect on energy output. This review summarizes the research progress in novel in-situ integrative photovoltaic-storage tandem cells, classified by silicon solar cell, sensitized solar cell and perovskite solar cell. Evaluation of methodology, operational principle, construction feature, and performance parameter are also discussed and critically reviewed, and the further development of in-situ integrative photovoltaic-storage tandem cell is also prospected.