{'fraction_non_alphanumeric': 0.046831955922865015, 'fraction_numerical': 0.017447199265381085, 'mean_word_length': 5.193181818181818, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Influence of p-type doping on perovskite solar cells fabricated with dithiophene-benzene copolymer as the hole-transporting layer

We fabricated perovskite solar cells (PSCs) employing high and low molecular weight dithiophene-benzene (DTB) copolymers as hole-transporting materials under nitrogen atmosphere. We then measured current density–voltage (J–V) characteristics of PSC devices in ambient air. After exposure to air for 5 h, device performance was poor and power conversion efficiency (PCE) was 3.05%. However, device performance gradually improved when the device was kept in dry air, and PCE was 16.20% after 173 h. This result indicates that the carrier density of DTB increased due to oxygen-doping. After oxygen-doping reached saturation, the superior molecular order of the high molecular weight DTB-based device yielded a higher PCE than the low molecular weight DTB-based device. When tris(pentafluorophenyl)borane (BCF) was added to DTB, the initial characteristics improved (PCE = 12.12%) further (PCE = 16.89%) by oxygen-doping, yielding the maximum PCE in this study.