Highly Strong and Tough Transparent Aramid Nanofiber Aerogel Films for Passive Heating Energy-Efficient Windows

Abstract

Aerogel energy-efficient glass can effectively reduce building energy consumption, but the low light transmission and weak mechanical properties greatly limit the application of aerogel in energy-efficient windows. Herein, a modified aramid nanofiber aerogel with outstanding mechanical strength (1.80 MPa, pull over 30000 times its weight), transparency (94.38% in the infrared region), and resistance to extreme environments (thermal insulation, frost resistance, flame retardancy, and self-extinguishing) is designed and synthesized using nanowire domain space structure strategy. The aerogel used for energy-efficient windows to reduce energy consumption in buildings is demonstrated. When the aerogel energy-efficient windows are applied in winter, the average temperature of the energy-efficient windows during the period from 10:00 a.m. to 4:00 p.m. is 4.01 and 7.01 °C higher than the ordinary glass house and the outdoor temperature, respectively. Carbon reduction calculations show that even in the coldest provinces of China, poly(terephthaloyl chloride-co-phenylenediamine-co-2-(4-Aminophenyl)-1H-benzimidazol-5-amine) (PTPA) aerogel for passive heating can reduce CO₂ emissions by 94.14 Kg m⁻² per year. This study provides a new strategy for synthesizing transparent aramid aerogels and a new way to develop passive heating and warming energy-efficient windows for the next generation of energy-efficient and environmentally friendly buildings.