Abstract At present, reducing the defect density at grain boundaries is still the main method to improve the performance of perovskite photodetectors. The increase of grain size can also improve the performance of perovskite photodetectors. In this work, we added POM @ g-C3N4 as a dopant into the perovskite precursor solution for the first time. The doping of g-C3N4 can control the crystallization rate of perovskite, thereby passivating the charge recombination center at the grain boundary to reduce the defect density. However, the conduction band energy level of g-C3N4 is higher than that of perovskite, which is not conducive to electron transmission. Polyoxometalate (POM) H3PMo12O40 (PMo12) has very good ultraviolet–visible light absorption. Adding it to perovskite can improve the ultraviolet–visible light absorption of the perovskite layer. Furthermore, the energy level of the polyoxometalate PMo12 matches the perovskite layer, which promotes the electron transport. Adding the composite material to the perovskite precursor solution not only increases the grain size of the perovskite crystals from 100 nm to 300 nm, but also increases the light absorption of the perovskite layer. Consequently, the photocurrent increased from 4.5 μA to 11.5 μA under the double regulation of the composite material, which is 2.6 times of the photocurrent of the reference group. This work provides a method of double adjustment of composite materials to increase the photocurrent of photodetectors.

中文翻译：

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g-C3N4@PMo12复合材料双调提高钙钛矿基光伏器件性能

摘要 目前，降低晶界缺陷密度仍是提高钙钛矿光电探测器性能的主要方法。晶粒尺寸的增加也可以提高钙钛矿光电探测器的性能。在这项工作中，我们首次将 POM@g-C3N4 作为掺杂剂添加到钙钛矿前驱体溶液中。g-C3N4的掺杂可以控制钙钛矿的结晶速率，从而钝化晶界处的电荷复合中心，降低缺陷密度。但g-C3N4的导带能级高于钙钛矿，不利于电子传输。多金属氧酸盐 (POM) H3PMo12O40 (PMo12) 具有非常好的紫外-可见光吸收。将其添加到钙钛矿中可以提高钙钛矿层的紫外-可见光吸收。此外，多金属氧酸盐 PMo12 的能级与钙钛矿层相匹配，从而促进了电子传输。在钙钛矿前驱体溶液中加入复合材料，不仅使钙钛矿晶体的晶粒尺寸从 100 nm 增加到 300 nm，而且增加了钙钛矿层的光吸收。因此，在复合材料的双重调节下，光电流从 4.5 μA 增加到 11.5 μA，是参考组光电流的 2.6 倍。该工作提供了一种双调节复合材料以增加光电探测器光电流的方法。在钙钛矿前驱体溶液中加入复合材料，不仅使钙钛矿晶体的晶粒尺寸从 100 nm 增加到 300 nm，而且增加了钙钛矿层的光吸收。因此，在复合材料的双重调节下，光电流从 4.5 μA 增加到 11.5 μA，是参考组光电流的 2.6 倍。该工作提供了一种双调节复合材料以增加光电探测器光电流的方法。在钙钛矿前驱体溶液中加入复合材料，不仅使钙钛矿晶体的晶粒尺寸从 100 nm 增加到 300 nm，而且增加了钙钛矿层的光吸收。因此，在复合材料的双重调节下，光电流从 4.5 μA 增加到 11.5 μA，是参考组光电流的 2.6 倍。该工作提供了一种双调节复合材料以增加光电探测器光电流的方法。