Ito Nozomi, Kamarudin Muhammad Akmal, Hirotani Daisuke, Zhang Yaohong, Shen Qing, Ogomi Yuhei, Iikubo Satoshi, Minemoto Takashi, Yoshino Kenji, Hayase Shuzi
Graduate School of Life Science and Systems Engineering , Kyushu Institute of Technology , 2-4 Hibikino , Wakamatsu-ku, Kitakyushu-shi , Fukuoka-ken 808-0196 , Japan.
Faculty of Informatics and Engineering , The University of Electro-Communications , 1-5-1 Chofugaoka , Chofu , Tokyo 182-8585 , Japan.
J Phys Chem Lett. 2018 Apr 5;9(7):1682-1688. doi: 10.1021/acs.jpclett.8b00275. Epub 2018 Mar 20.
Lead-based perovskite solar cells have gained ground in recent years, showing efficiency as high as 20%, which is on par with that of silicon solar cells. However, the toxicity of lead makes it a nonideal candidate for use in solar cells. Alternatively, tin-based perovskites have been proposed because of their nontoxic nature and abundance. Unfortunately, these solar cells suffer from low efficiency and stability. Here, we propose a new type of perovskite material based on mixed tin and germanium. The material showed a band gap around 1.4-1.5 eV as measured from photoacoustic spectroscopy, which is ideal from the perspective of solar cells. In a solar cell device with inverted planar structure, pure tin perovskite solar cell showed a moderate efficiency of 3.31%. With 5% doping of germanium into the perovskite, the efficiency improved up to 4.48% (6.90% after 72 h) when measured in air without encapsulation.
近年来，铅基钙钛矿太阳能电池取得了进展，其效率高达20%，与硅太阳能电池相当。然而，铅的毒性使其成为太阳能电池应用的不理想候选材料。相比之下，锡基钙钛矿因其无毒性质和丰富储量而被提出。不幸的是，这些太阳能电池存在效率低和稳定性差的问题。在此，我们提出一种基于锡和锗混合的新型钙钛矿材料。通过光声光谱测量，该材料的带隙约为1.4 - 1.5 eV，从太阳能电池的角度来看这是理想的。在具有倒置平面结构的太阳能电池器件中，纯锡钙钛矿太阳能电池的效率为中等的3.31%。当在空气中无封装条件下测量时，向钙钛矿中掺入5%的锗后，效率提高到4.48%（72小时后为6.90%）。
