中间带太阳电池进展

中间带太阳电池是第三代光伏发电研究中很热门的研究领域之一。论述了中间带太阳电池的原理,以及实现中间带材料的三种方法,即量子点中间带电池、杂质带电池、高失配合金。量子点中间带太阳电池的红外吸收测量证实中间带太阳电池的基本原理是正确的。介绍了为提高短路电流,采用应力补偿技术,增加量子点层数,增大量子点的吸收系数。目前量子点中间带太阳电池的效率达到18%。阐述了杂质带的机理,研究表明,当Si中掺Ti浓度超过Mott相变浓度时,杂质抑制非辐射复合,有效载流子寿命增加。高失配合金具有不寻常的能带结构,AlGaN材料的带隙接近中间带的理想值,很可能成为下一个研究的热点。

Progress in Intermediate Band Solar Cells

The intermediate band solar cell(IBSC) is one of the popular research fields in the study of the third generation photovoltaics.The principle of the IBSC is discussed,and the three methods to realize intermediate band material,including quantum dot intermediate,impurity intermediate band,and highly mismatched alloys,are also discussed.Proved by the infrared absorption measurement of the quantum dot IBSC,the IBSC basic principle is correct.In order to improve the short circuit current,the stress compensation technology is adopted,the layer number and absorption coefficient of the quantum dot are increased.The efficiency of the quantum dot IBSC is 18% at present.The mechanism of the impurity band is discussed,the research shows that when the Ti-impurity concentration in Si is beyond the Mott phase change concentration,the impurity restrains the nonradiative recombination,and the effective carrier lifetime is increased.The highly mismatched alloy exhibits unusual energy band structure.The band gap of AlGaN is very close to the optimum value of the intermediate band,so it will be the next research hot spot.