Lu Li,Weiyi Chen,Meng Wang,Xinjiang Shi,Shiming Zhang,Debao Xiao
In this paper, we present the first application of organic hole-transporting semiconductors 4,4′,4′'-tris(carbazol-9-yl)triphenylamine (TCTA) and 4,4′-cyclohexylbis[N,N-bis(4-methylphenyl) aniline] (TAPC) in electrochromism area, demonstrating that TCTA or TAPC is suitable for use as hole-transporting materials on the anode of 1,1′-bis(3-sulfopropyl) viologen (SPV)-based electrochromic devices. For such devices, we obtain a decreased driving voltage of SPV-based electrochromic devices down to −2.0 V in the presence of TCTA or TAPC with comparison to that of ca. −2.5 V in the absence of the hole-transporting material. The optical contrast of the device increased from 57.19 % (without hole-transport layer) to 66.41 % (TCTA) or 62.97 % (TAPC) at 533 nm. The response time of 66.2 s in the absence of hole-transporting layer can decrease to 30.6 s with TCTA and 62.7 s with TAPC, respectively. The coloration efficiency of the as-fabricated devices at 533 nm can reach from 67.3 cm 2 /C (SPV-only) up to 153.2 cm 2 /C (TCTA) and 80.5 cm 2 /C (TAPC). This work paved a new way for boosting electrochromic performances of viologen-based devices via electrode modification of anode by hole-transporting material TCTA and TAPC which have been used effectively and efficiently in organic electroluminescent devices and solar cells.
Guo He,Dezhi Yang,Sizhe Tao,Liqing Yang,Dechao Guo,Jingbo Zheng,Ji Li,Jiangshan Chen,Dongge Ma
Perovskite photodetectors (PPDs) offer a promising solution with low cost and high responsivity, addressing the limitations of traditional inorganic photodetectors. However, there’s still room for improvement in terms of dark current and stability of air-processed PPDs. In this study, 4',4"-Tris(carbazl-9-yl)-triphenylamine (TCTA) is utilized as nucleation agent to enhance the quality of perovskite film. The synergistic effect of TCTA and moisture promotes rapid nucleation of PbI2-PbCl2, resulting in an increased nucleation rate and the elimination of pinholes in the film. By employing additive engineering, we obtain a PbI2-PbCl2 layer with high coverage, leading to a lower density of traps in the corresponding perovskite film. Consequently, the modified PPD exhibits a remarkable reduction in dark current density by over one order of magnitude, reaching 2.4×10-10 A cm-2 at -10 mV, along with a large linear dynamic range (LDR) of 183 dB. Furthermore, the resulting PPD demonstrates remarkable stability, retaining 90% of the initial external quantum efficiency (EQE) value even after continuous operation for over 3200 hours. Due to a fast response time in nanosecond range, the PPD can convert modulated light signals into electrical signals at a speed of 588 Kbit s-1, highlighting great potential in the field of optical communication.