Recently, many colleges and universities' laboratories have shown good news: Prof. Han Liyuan of Shanghai Jiaotong University made a statement. The team lasted 3 years on the basis of the preparation of large-area high-quality perovskite films, and developed a perovskite battery module with an effective area of ​​36.1cm2. For the first time, international certification agencies have achieved 12.1% certification efficiency. The emergence of this achievement means that the future of perovskite PV technology has the potential to go beyond the laboratory and achieve large-scale industrialization. The new perovskite solar cell independently developed by Huazhong University of Science and Technology is actively preparing for mass production. The Huake team has obtained more than 16% of the photoelectric conversion efficiency, and the cost per peak watt is only 1/5 of that of traditional solar cells, and each square meter is expected. The cost will be as low as 100 yuan. Photoelectric conversion rate When referring to new photovoltaic materials, the first consideration is the photoelectric conversion rate. Some students will ask why the photoelectric conversion rate of perovskite solar cells mentioned in the above two news reports differs by 4 percentage points. This data difference is due to several reasons: First, the photoelectric conversion rate of the perovskite battery is directly related to the area and thickness of the battery. Depending on the existing technology for preparing the thin film, the larger the area of ​​the perovskite film, the easier the flaws occur and the lower the efficiency of the battery. The area of ​​perovskite solar cell modules with more than 20% international certification efficiency can only reach 0.04 to 0.2 square centimeters, which is at most like that of rice. The 12.1% proposed by Shanghai Jiaotong University is under the premise of an area of ​​36.1 cm2. Second, in this perovskite ABX3 structure, A is a methylamino group (CH3NH3), B is a metal lead atom, and X is a halogen atom such as chlorine, bromine, or iodine. Because the relatively complex crystal structure has higher requirements on the atom (or radical) radius at the three sites of A, B, and X, the composition of the perovskite light-absorbing material is relatively fixed. Recently, some research groups replaced methylamine at the A position with methylimidazole, narrowing the band gap (1.48 eV) and obtaining higher photocurrent. For the Pb atom in the B position, there has been no report of photoelectric response after the Sn atom replaces the Pb atom. Atomic atoms in the X-position can currently use halogen atoms such as chlorine, bromine, and iodine. However, only the iodine-based perovskite has a suitable bandgap to achieve high conversion efficiency. In addition to CH3NH3PbI3, CH3NH3PbI3-xClx is currently the most studied material. Under the condition of keeping the energy level structure basically unchanged, the doping of a small amount of chlorine can increase the electron mobility and show more excellent photoelectric properties. Therefore, changes in some elements also have a profound effect on the photoelectric conversion rate. The most common perovskite material in high-performance perovskite solar cells is lead methylamine iodide CH3NH3PbI3 with a bandgap of about 1.5 eV. (Theoretic studies have shown that the energy gap is between 1 and 1.5 eV. The absorption efficiency of sunlight is the highest. The energy gap of the typical perovskite ABX3 mostly falls within this range, and the extinction coefficient is high. A few hundred nanometers thick film can fully absorb the sunlight below 800 nm. Moreover, this material is simple to prepare, and a solution containing PbI2 and CH3NH3I can be obtained by spin coating at room temperature to obtain a uniform film. The above characteristics make the perovskite-type structure CH3NH3PbI3 not only achieve absorption of visible light and part of near-infrared light, but also the generated photocarriers are not easy to recombine, and the energy loss is small. This is a perovskite type solar cell that can achieve high efficiency. root cause. Hp Graphite Electrode,Graphite Electrodes Hp,Nipples Electrode Graphite,Carbon Graphite Electrode For Sale Carbographite Industrial PTE.LTD , https://www.graphites.pl