Bai, Yiming; Tian, Shilei; Guan, Yuzhe; Wang, Xi; Wang, Fuzhi; Li, Meicheng; Tan, Zhan'ao; Liu, Guicheng Source: Small, 2024; ISSN: 16136810, E-ISSN: 16136829; DOI: 10.1002/smll.202402903; Publisher: John Wiley and Sons Inc

Articles not published yet, but available online Article in Press

Author affiliation:

State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing; 102206, China

Key Laboratory of Semiconductor Materials Science, Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, Beijing; 100083, China

School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing; 102206, China

Beijing Laboratory of New Energy Storage Technology, North China Electric Power University, Beijing; 102206, China

Abstract:

Integrated electrochromic devices powered by photovoltaic cells have evoked a lot of interest due to their promising commercial prospects. However, their application has been restricted by the voltage adaption between the self-powered voltage and the color-changing threshold voltage (Vt). Herein, a strategy of bidirectional voltage regulating is proposed to develop a novel stand-alone integrated photovoltachromic device (I-PVCD), which integrates perovskite/organic tandem solar cells (P/O-TSCs) to drive color-changing process of conjugated poly(3-hexylthiophene) (P3HT) films. To lower the driving-voltage of electrochromic layer, C60 is introduced to decrease the onset oxidation potential of P3HT film, and thus leading to a reduced Vt of 0.70 V benefiting from the enhanced highest occupied molecular orbital level and decreased charge transfer resistance from 67.46 to 49.89 Ω. Simultaneously, PBDB-T is utilized as the hole transport layer in the interconnecting layer of CsPbI2Br/PTB7-Th:IEICO-4F P/O-TSC to improve its open-circuit voltage (Voc) to 1.85 V. Under their synergetic merits, a I-PVCD with a wider self-adaptive voltage range is achieved. This device can undergo fast and reversible chromic transition from beautiful magenta to transparent only under the solar radiation, and demonstrates a coloration efficiency of 351.90 cm C and a switching time of 2 s besides its excellent operating reliability.