Herein, we report a facile method to reduce the J–V hysteresis using nickel oxide(NiO_x)/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) double hole transport layer (DHTL) fabricated p-i-n perovskite solar cells. The device using the NiO_x/PEDOT:PSS DHTL shows a reduced hysteresis with an average hysteresis index of 0.020. This is smaller than a single NiO_x device (0.142) or single PEDOT:PSS (0.093). First-principles calculations reveal that O and S in PEDOT:PSS couple with the Ni in NiO_x, and PSS forms hydrogen bonds with O on NiO_x. This coupling generates an interfacial dipole moment directed toward the PEDOT: PSS layer, evidenced by dark current-voltage plots. Electrochemical impedance spectroscopy (EIS) indicates that these dipoles lead to kinetically-favorable charge extraction and contribute to the suppressed hysteresis. Kelvin probe force microscopy indicates that the generated dipoles dispel the accumulated iodine ion vacancies at the hole transport layers side that enhanced charge collection and thereby decreased the hysteresis. Intensity modulated photocurrent spectroscopy demonstrates that the device with the NiO_x/PEDOT:PSS DHTL shows faster charge transport rate k_trans than that of device with single PEDOT:PSS or NiO_x, and further demonstrates that a more efficient outward charge flow in PSCs with the NiO_x/PEDOT:PSS DHTL reduces hysteresis.

本文中，我们报告了一种使用氧化镍（NiO _x）/聚（3,4-乙撑二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT：PSS）双孔传输层（DHTL）制成的针状钙钛矿降低J–V磁滞的简便方法太阳能电池。使用NiO _x / PEDOT：PSS DHTL的设备显示出降低的磁滞，平均磁滞指数为0.020。这比单个NiO _x设备（0.142）或单个PEDOT：PSS（0.093）小。第一性原理计算表明，PEDOT：PSS中的O和S与NiO _x中的Ni耦合，而PSS与NiO _x上的O形成氢键_。这种耦合会产生一个指向PEDOT：PSS层的界面偶极矩，这由暗电流-电压图证明。电化学阻抗谱（EIS）表明，这些偶极子会导致动力学上有利的电荷提取，并有助于抑制磁滞现象。开尔文探针力显微镜检查表明，产生的偶极子消除了空穴传输层一侧累积的碘离子空位，从而增强了电荷收集，从而降低了磁滞现象。强度调制光电流光谱法表明，具有NiO _x / PEDOT：PSS DHTL的器件显示的电荷传输速率k _trans比具有单个PEDOT：PSS或NiO _x的器件更快。，并进一步证明，使用NiO _x / PEDOT：PSS DHTL在PSC中提供更有效的向外电荷流动可减少磁滞现象。