Photovoltaics Laboratory , Korea Institute of Energy Research , 152 Gajeong-ro , Yuseong-gu, Daejeon 34129 , Republic of Korea.
Department of Materials Science and Engineering , Yonsei University , Seoul 03722 , Korea.
ACS Appl Mater Interfaces. 2019 Nov 20;11(46):43244-43251. doi: 10.1021/acsami.9b16144. Epub 2019 Nov 11.
Control of the constituent phase and stoichiometry of iron pyrite (FeS) is a prerequisite for high-performance photovoltaic devices based on this material. If the pyrite contains sulfur-deficiency-related secondary phases which have a metallic character and a high possibility of coexistence in pyrite films, then significant carrier recombination is expected. In this work, the beneficial role of Na in suppressing the formation of nanoscale or amorphous sulfur-deficient secondary phases is reported with experimental evidence, leading to a higher phase purity for solution-processed pyrite films. The potential reduction of charge recombination via these metallic secondary phases results in significant improvements in both the photopotential and photocurrent intensity of Na-modified pyrite films compared with reference samples.
控制黄铁矿（FeS）的组成相和化学计量比是基于该材料的高性能光伏器件的前提条件。如果黄铁矿中含有与硫缺陷相关的具有金属特性且很可能在黄铁矿薄膜中共存的次要相，则预计会发生显著的载流子复合。在这项工作中，通过实验证据报道了 Na 抑制纳米级或非晶态硫缺陷次生相形成的有益作用，从而提高了溶液处理黄铁矿薄膜的相纯度。通过这些金属次生相降低电荷复合的可能性，与参考样品相比，Na 改性黄铁矿薄膜的光电位和光电流强度都有显著提高。
