Wide-Spectrum Modulated Electrochromic Smart Windows Based on MnO₂/PB Films

Abstract

Inorganic materials have been extensively studied for visible electrochromism in the past few decades. However, the single inorganic electrochromic (EC) material commonly exhibits a single color change, leading to a narrow spectrum of modulation, which offsets or limits the maximally energy-saving ability. Here, we present a wide-spectrum modulated EC device designed by combining the complementary EC nanocomposite of manganese dioxide (MnO 2 ) and Prussian blue (PB) for enhanced energy savings. Porous MnO 2 nanostructures serve as host frameworks for the templated growth of PB, resulting in MnO 2 /PB nanocomposites. The complementary optical modulation ranges of MnO 2 and PB enable a widen-spectrum modulation across the solar region with the development of the MnO 2 /PB nanocomposite. The colored MnO 2 /PB device exhibited an optical modulation of 32.1% in the wide solar spectrum range of 320−1100 nm and blocked 72.0% of the solar irradiance. Furthermore, fast switching responses (2.7 s for coloration and 2.1 s for bleaching) and a high coloration efficiency (83.1 cm 2 •C −1 ) of the MnO 2 /PB EC device are also achieved. The high EC performance of the MnO 2 /PB nanocomposite device provides a new strategy for the design of highperformance energy-saving EC smart windows.

Novel Prussian White@MnO2-Based Inorganic Electrochromic Energy Storage Devices with Integrated Flexibility, Multicolor, and Long Life

“…The cluster morphology was different from that in the Prussian blue film and MnO 2 /PB composite films as stated in previous studies. 42,43 It is explained that the MnO 2 nanoparticle was also uniformly deposited on a reduced Prussian white (PW) cluster, not only on a film surface. From the lower-resolution SEM image of PW@MnO 2 , the crack gap interval was dotted with a spherical cluster on the film surface (Figure S5c).…”

“…In contrast to the tedious preparation method in the literature, PW@MnO 2 can be obtained facilely by step-by-step electrodeposition within 8 min in this work, while there was at least 9 h for one-time formation of the MnO 2 film in the literature. 42 The common electrochromic cathodic material WO 3 acted as the EESD negative electrode and was prepared by magnetron sputtering. A flexible Li-based solid-state EESD was successfully fabricated by the electrolyte solidification method.…”

An electrochemically stable Ag@Au–Co core–shell nanowire network-based transparent conductor for flexible self-powered Zn-based electrochromic smart devices

“…Electrochromic smart windows can present different color response when different voltage was inputted, and it is attracting increasing interest for reducing the building energy consumption [58][59][60][61][62] . In comparison with rigid ECDs, flexible ECDs can be installed onto the pristine glass window without replacing all windows 63 .…”

Towards two-dimensional color tunability of all-solid-state electrochromic devices using carbon dots

“…Electrochromic devices (ECDs) have attracted increased attention in smart windows, displays and color-tuneable optical elements because of their zero energy consumption when at various working states ( Ma et al, 2021 ; Kim et al, 2021 ; Cui et al, 2019 ; Seong et al, 2018 ; Park et al, 2017 ; Wu et al, 2021 ). Especially, multicolor electrochromic displays are one of the most versatile applications because they can retain their colored states without the need to supply electrical power.…”