Hierarchical Porous Aerogel Research Articles

Carbon-intercalated halloysite-based aerogel efficiently encapsulating phase change materials with excellent photothermal conversion and energy storage

Latent heat storage systems based on organic phase change materials (PCMs) are considered to be an efficient solar energy utilization strategy, but leakage vulnerability and insensitivity to sunlight of PCMs limit their further application in energy storage. In this work, a new hierarchical porous aerogel was constructed with the carbon intercalated halloysite nanotubes (CHNTs) as the assembly units for PCMs encapsulation to improve the load weight, stability and sunlight absorption. The CHNTs were first successfully synthesized through intercalation and carbonization, with the aim of increasing their specific surface area and sunlight absorption.Subsequently, the CHNTs/polyvinyl alcohol (PVA) aerogels with 3D honeycomb structure were prepared by self-assembly using a freeze-drying method, which can significantly promote the encapsulation ratio of lauric acid (LA) in the pores of both aerogels and CHNTs. The CHNTs can not only improve compressive strength of the aerogels and shape stability of the composite PCMs, but also enhance light absorption ability of the composites compared to pristine HNTs. As a support material, CHNTs aerogel (CHNP) loaded more than 92 wt% PCM (LA@CHNP) and exhibited an extremely high latent heat capacity (170.9 J/g). The LA@CHNP had good structural and thermal stability in 300 cycles without visible leakage. Besides, solar energy absorption increased from 43 % to 98 %, and the solar-to-thermal energy conversion efficiency increased to 95.88 %, which could be attributed to 3D porousness and carbon nanolayers of the CHNTs. We have successfully synthesized an eco-friendly and facile composite LA@CHNP, which will contribute to the design of advanced composites with excellent solar energy storage properties, and provide a new direction for the application of carbonized materials.

A Hierarchical Porous Aerogel Prepared from Conjugated Polymer for Rapid and Effective Removal of Organic Micro‐Pollutants from Water

AbstractWater pollution caused by organic micro‐pollutants is seriously harmful to aquatic ecosystem and human health. In this work, a hierarchical porous aerogel (HPAG) prepared from rigid conjugated polymers is used to remove organic micro‐pollutants from water. Thanks to the hierarchical porous structure and rich π electrons, HPAG showed a fast adsorption rate and high adsorption capacity for adsorbates. The maximum equilibrium adsorption capacity of HPAG for bisphenol A, 1‐naphthylamine, and naphthalene is 60.5, 50.9 and 63.9 mg g−1 at 10 ppm, respectively, and the adsorption behaviors were in accordance with the Freundlich model. HPAG exhibited a high preference in adsorbing organic micro‐pollutants with high hydrophobicity, and the removal efficiency for polycyclic aromatic hydrocarbons reached over 95%. The HPAG can be easily recycled and regenerated after washing with dichloromethane, and the adsorption performance maintained above 82% after 5 cycles.