Hole transport materials (HTMs) with different hole extraction abilities play an important role in dictating the efficiency of the perovskite solar cells (PSCs). Besides, employing a donor acceptor (D-A) random copolymer HTM to bring out deeper HOMO energy level is highly beneficial to the hole extraction and durability of PSCs. In this context, a highly soluble D-A based random copolymeric benzodithiophene-thienopyrroledione-thienothiophene derivatives (RCP-BTT) HTM has been derived from the backbone structure of Poly({4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl}) (PTB7). The synthesized dopant-free RCP-BTT HTM shows a deeper HOMO energy level (−5.28 eV) due to its high compatibility than PTB7 level (−5.15 eV) based on perovskite energy level. Gradient band alignment of RCP-BTT has provided efficient hole extraction in the PSCs made of Cs-containing triple cation perovskite as absorber resulting in the efficient photovoltaic performance of RCP-BTT. The RCP-BTT with dopant shows significantly increased V_oc (1.09 V) with respect to that of parent PTB7 (V_oc of 1.06 V), resulting in an enhanced efficiency of 14.57% than that of PTB7 (12.02%). On the whole, the improvement in photovoltaic performance of PSC based on the polymeric RCP-BTT HTM is attributable to its deeper HOMO energy level and exceptional hole extraction ability.

具有不同空穴提取能力的空穴传输材料（HTM）在决定钙钛矿太阳能电池（PSC）的效率方面起着重要作用。此外，采用施主受体（DA）无规共聚物HTM产生更深的HOMO能级，对PSC的空穴提取和耐用性非常有利。在这种情况下，从聚（{4,8-双[（2-乙基己基）氧基]苯并[1] ，2-b：4，5-b′]二噻吩-2，6-二基} {3-氟-2-[（2-乙基己基）羰基]噻吩并[3，4-b]噻吩二基}）（PTB7）。合成的不含掺杂剂的RCP-BTT HTM具有比基于钙钛矿能级的PTB7能级（−5.15 eV）高的相容性，因此具有更高的HOMO能级（−5.28 eV）。RCP-BTT的梯度带取向在由含Cs的三阳离子钙钛矿作为吸收剂制成的PSC中提供了有效的空穴提取，从而实现了RCP-BTT的高效光伏性能。带有掺杂剂的RCP-BTT显着增加V _OC（1.09 V）相对于该父PTB7（的V _OC 1.06的V），导致比PTB7（12.02％）的14.57％的增强的效率。总体而言，基于聚合物RCP-BTT HTM的PSC光伏性能的提高归因于其更深的HOMO能级和出色的空穴提取能力。