# Energy, Society, and the Environment/Aerogel

Aerogel, worlds lightest and least dense solid. It is 99.8% air and has a porous solid network that contains air pockets, with the air pockets taking up the majority of space within the material and some aerogel are so light that if the air is removed from it it will be less dense than air. its mostly transparent it appears smoky blue against dark backgrounds and yellowish against bright backgrounds. aerogels are solid, rigid, and dry materials. It has a property of friability although modern variations do not suffer from this that much. Aerogels are one of the best thermal insulators because they almost nullify two of the three methods of heat transfer conduction and convection. It is produced by a sol–gel process followed by supercritical drying of the wet gel in an autoclave and porosity extends from about 1 to 100 nm as a result why properly made aerogels are highly transparent. Aerogel can be made from variety of material but silica aerogels are mostly used and studied Aerogels have many application such as Batteries, Dielectric Materials, Piezoelectric Materials, Cosmic (Comet) Dust Collection by Silica, Aerogels for Inertial Confinement Fusion(ICF),Silica Aerogels for Nuclear Waste Storage, Applications in Fundamental Sciences, Application of Aerogels in Catalysis, Silica Aerogel and Life Science, however the most common use of aerogel is seen on thermal and electric application, Another common use of aerogel is water proofingit works great as a hydrophobic insulator.

## Use Of Aerogel In Lithium-Sulfur Battery

lithium–sulfur battery is a type of rechargeable battery, which is better than traditional lithium ion battery notable for its high specific energy and storage and showing a prominent growth in the industry. Aside all of these prominent advantages this kind of battery has a major flaw such as using lithium-metal anode results in lithium dendrite formation, which creates short-circuiting, and explosions of cells,sulfur being very low electronic conductive material, dissolved lithium polysulfides between the sulfur cathode and the lithium anode as a result of chemical reaction, volume expansion of active sulfur in its charging cycle makes its performance poor and low Coulombic efficiency. So to solve this issue graphene based aerogel proved prominent results such as using Li 2 S-coated N- or B-doped graphene aerogel cathode has improved battery capacity, performance, and cycle stability compared to the undoped ones, another graphene base aerogel would be PGCNF/S aerogel as a cathode which results in a better electron flow shortened diffusion distance of lithium ions, long term cycling stability up to 600 cycles, and average Coulombic efficiency.
* ↑ Aerogels by Jochen Fricke Andreas Emmerling https://ceramics.onlinelibrary.wiley.com/doi/abs/10.1111/j.1151-2916.1992.tb04461.x
* ↑ Aerogels: production, characterization, and applications https://www.jstage.jst.go.jp/article/kona/15/0/15_1997008/_pdf
* ↑ Chemistry of Aerogels and Their Applications https://is.muni.cz/el/1431/podzim2006/C7780/um/Read/2711172/aerogel_Pajonk_ChRev02_4243.pdf
* ↑ Aerogel-based thermal insulation https://www.sciencedirect.com/science/article/abs/pii/S0022309398001252
* ↑ Electrochemical Properties of Carbon Aerogel Electrodes: Dependence on Synthesis Temperature file:///C:/Users/hp/Downloads/molecules-24-03847.pdf
* ↑ https://journals.sagepub.com/doi/abs/10.1177/0040517515591781
* ↑ High-Performance Lithium-Sulfur Batteries with a Self Supported, 3D Li 2 S-Doped Graphene Aerogel Cathodes http://utw10370.utweb.utexas.edu/publications/P163.pdf
* ↑ Self-supported 3D Aerogel Network Lithium Sulfur Battery Cathode: Sulfur Spheres Wrapped with Phosphorus Doped Graphene and Bridged with Carbon Nanofibers https://www.researchgate.net/profile/Hao-Hu-50/publication/340044616_Self-supported_3D_Aerogel_Network_Lithium_Sulfur_Battery_Cathode_Sulfur_Spheres_Wrapped_with_Phosphorus_Doped_Graphene_and_Bridged_with_Carbon_Nanofibers/links/5ea6ed1645851553fab2f565/Self-supported-3D-Aerogel-Network-Lithium-Sulfur-Battery-Cathode-Sulfur-Spheres-Wrapped-with-Phosphorus-Doped-Graphene-and-Bridged-with-Carbon-Nanofibers.pdf
* ↑ High-Performance Lithium-Sulfur Batteries with a Self Supported, 3D Li 2 S-Doped Graphene Aerogel Cathodes http://utw10370.utweb.utexas.edu/publications/P163.pdf
* ↑ Self-supported 3D Aerogel Network Lithium Sulfur Battery Cathode: Sulfur Spheres Wrapped with Phosphorus Doped Graphene and Bridged with Carbon Nanofibers https://www.researchgate.net/profile/Hao-Hu-50/publication/340044616_Self-supported_3D_Aerogel_Network_Lithium_Sulfur_Battery_Cathode_Sulfur_Spheres_Wrapped_with_Phosphorus_Doped_Graphene_and_Bridged_with_Carbon_Nanofibers/links/5ea6ed1645851553fab2f565/Self-supported-3D-Aerogel-Network-Lithium-Sulfur-Battery-Cathode-Sulfur-Spheres-Wrapped-with-Phosphorus-Doped-Graphene-and-Bridged-with-Carbon-Nanofibers.pdf