The inadequate hole injection limits the efficiency and lifetime of the blue quantum dot light‐emitting diodes (QLEDs), which severely hampers their commercial applications. Here a new discotic molecule of 3,6,10,11‐tetrakis(pentyloxy)triphenylene‐2,7‐diyl bis(2,2‐dimethylpropanoate) (T5DP‐2,7) is introduced, in which the hole transport channels with superior hole mobility (2.6 × 10 –2 cm 2 V –1 s –1 ) is formed by stacking. The composite hole transport material (HTM) is prepared by blending T5DP‐2,7 with the cross‐linked 4,4′‐ bis(3‐vinyl‐9H‐carbazol‐9‐yl)‐1,1′biphenyl (CBP‐V) which shows the deep highest occupied molecular orbital energy level. The increased hole mobility of the target composite HTM from 10 –4 to 10 –3 cm 2 V –1 s –1 as well as the stepwise energy levels facilitates the hole transport, which would be beneficial for more balanced carrier injection. This composite hole transport layer (HTL) has improved the deep‐blue‐emission performances of Commission International de I'Eclairage of (0.14, 0.04), luminance of 44080 cd m −2 , and external quantum efficiency of 18.59%. Furthermore, when L 0 is 100 cd m −2 , the device lifetime T 50 is extended from 139 to 502 h. The state‐of‐the‐art performance shows the successful promotion of the high‐efficiency for deep blue QLEDs, and indicates that the optimizing HTL by discotic molecule stacking can serve as an excellent alternative for the development of HTL in the future.

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The absent photo‐response in near‐infrared (NIR) light (>800 nm) of lead‐based perovskite solar cells (PSCs) limits the further improvement of their power conversion efficiency (PCE). Here, a narrow bandgap p‐type phthalocyanine derivative (Copper(II) 2,3,9,10,16,17,23,24‐octakis((4‐(bis(4‐methoxyphenyl)amino)phenyl)ethynyl)phthalocyanine –8TPAEPC) with NIR absorption is synthesized to extend the photovoltaic response of perovskite to 850 nm. After doping the 8TPAEPC into the perovskite photoactive layer, the perovskite crystal quality is improved, resulting in its good electrical conductivity and less surface defects. Furthermore, the molecules stacking on the grain boundaries construct the charge transportation paths, as well as the p–n bulk heterojunction with enhanced built‐in potential. The target PSCs are optimized with notably enhanced PCE from 20% up to 22.10%, and excellent stability that is over 80% of the initial level at 70–80% relative humidity can be maintained for more than 500 h, benefiting from the improved hydrophobicity of 8TPAEPC. In addition, 8TPAEPC also serves as a dopant‐free, highly carrier‐mobile, and moreover, NIR‐responsive hole transport layer (HTL) with boosted PCE of 20.42% that reaches state of the art level among the dopant‐free metal phthalocyanines HTL‐based PSCs.