Executive Summary : | The increasing global energy demand and consumption heavily rely on traditional fossil fuels, leading to environmental issues such as global warming. Despite extensive research on renewable energy sources, the share of renewable energy in total energy consumption remains low. In 2018, coal was the fastest primary energy consumption in the last decade, and oil and natural gas are predicted to remain for around 150 years. To reduce and optimize energy consumption, a major revolution in energy technology is necessary. Buildings use almost 30%-40% of primary energy worldwide, dominated by air conditioning for indoor cooling. Invisible near-infrared (NIR) radiation from solar irradiation accounts for about 50% of total solar energy reaching the earth and contributes significantly to solar heating and unpleasant indoor conditions.
This project aims to fabricate an electrochromic (EC) smart window that can absorb vis-to-NIR radiation by its redox-induced dark state selectively regulated by a small low voltage window. The project will introduce three solution-processable, low bandgap, novel donor-acceptor (D-A) type covalent organic frameworks with triphenylamine, biphenyl biscarbazole, and fused benzotrithiphene as donor moieties, respectively, and thiazolothiazole based acceptor as electrochromic materials (ECMs). The COFs-based ECMs will generate stable polaron or bipolaron states with lower bandgap to exhibit absorption in the NIR region with dark shades to regulate solar heat.
The project also plans to explore bright-to-dark electrofluorochromism with electrochromic devices (ECDs) and fabricate large-size devices for commercial viability. |