Multifunctional integrated electrochromic device by p-n conductive polymers for self-powered smart windows and miniaturized spectrometers
Xiaojian Zhang, Hao Lu, Juxuan Xie, Zhaohong Tan, Shuaiqi Li, Chongwu Gan, Wei Xiong, Xianghao Duan, Shuai Li, Zeshui Xu, K. B. Zhang, Yazhong Wang, Haoran Tang, Fei Huang
Abstract
Electrochromic devices enable dynamic modulation of light and heat, yet their broader adoption is hindered by limited color tunability, slow switching kinetics, and low coloration efficiency. Here, we present a complementary organic electrochromic device that addresses these challenges by employing dual conductive polymers: poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) and poly(benzodifurandione). The resulting device delivers exceptional performance, featuring a high optical contrast of 51% at 570 nm, ultrafast switching speeds (0.17/0.36 s for coloration/bleaching), a record-high coloration efficiency (1688 cm2 C⁻1 at 550 nm), and excellent cycling stability over 10,000 cycles. By integrating the device with a semitransparent organic solar cell, we realize a fully self-powered smart window with reducing indoor temperatures by 7 °C. Furthermore, coupling the electrochromic filter with a 4 × 4 organic photodetector array featuring on-chip Fabry–Pérot cavities enables a miniaturized spectrometer with 7.2 nm spectral resolution. This multifunctional electrochromic platform seamlessly bridges smart-window technology and spectral sensing, paving the way for energy-efficient, and compact optoelectronic systems. Electrochromic devices offer dynamic modulation of light and heat but suffer from limited color tunability, sluggish switching speeds, and low coloration efficiency, especially in inorganic electrochromic materials, which impede their widespread adoption. Here, the authors show a complementary organic electrochromic device that employs dual conductive polymers and overcomes these limitations.