In the vast realm of materials science, aerogel shines like a dazzling star, gradually transforming the development trajectories of multiple fields. What makes this magical material so unique that it captivates scientists and enterprises worldwide?
Aerogel, a solid material with a nano - porous network structure, is filled with gaseous dispersion media inside. It is one of the least dense solids in the world. Figuratively speaking, it is like "frozen smoke". More than 90% of its volume is vacuum, and its density is 1000 times less than that of glass. However, it possesses numerous astonishing and excellent properties.
In terms of thermal insulation performance, aerogel is truly the "king of thermal insulation". Its thermal conductivity is extremely low, ranging from 0.012 - 0.024W/(m·K), which is 2 - 3 orders of magnitude lower than that of traditional thermal insulation materials. There are three ways of heat transfer: heat convection, heat radiation, and heat conduction. The unique nano - sized porous structure of aerogel restricts the free flow of air within it, blocking heat convection. The staggered pores without "through - holes" reduce heat radiation. Heat is transferred along countless pores, and the path is infinitely long, greatly weakening heat conduction. Thanks to these properties, aerogel has shown its prowess in the aerospace field. The "Zhu Rong" Mars rover is covered with aerogel, which can ensure the normal operation of the rover in a landing environment of up to 1000°C and an extreme low temperature of - 130°C.
In addition to the aerospace field, the applications of aerogel in industry and daily life are becoming more and more extensive. In the petrochemical industry, large - scale distillation towers and complex pipeline systems require efficient thermal insulation. The excellent thermal insulation effect of aerogel can significantly reduce heat loss. Its light weight and thinness can also reduce the weight of equipment and save space. In the construction field, using aerogel as a thermal insulation material can greatly improve the energy efficiency of buildings, reduce heating and cooling costs, and contribute to the goal of achieving green buildings. In outdoor clothing, the addition of aerogel has greatly enhanced the warmth - retaining performance of clothing while maintaining lightness and breathability, providing a better experience for outdoor sports enthusiasts.
However, the large - scale application of aerogel also faces challenges. On the one hand, its preparation cost is relatively high. Whether it is the complex equipment required for supercritical drying or the high - demand for the formula and process in atmospheric pressure drying, both increase the production cost. On the other hand, aerogel has low strength and poor toughness. Ordinary aerogel can be easily crushed by fingers, and its structural stability needs to be improved.
Nevertheless, researchers and enterprises have never stopped exploring. In recent years, new preparation techniques and modification methods have emerged continuously, aiming to reduce costs and improve performance. With the continuous progress of technology, aerogel is expected to break through the existing limitations, move from the laboratory to a broader market, deeply integrate into people's lives, inject new impetus into the development of various industries, and open a new chapter in material applications.