Application of Carbon Aerogels in Lithium-Air Batteries
One of the main challenges with today’s batteries is their relatively low volumetric and specific capacities. The highest specific capacity can be achieved with lithium-air batteries, which use metallic lithium as the anode and typically some form of porous carbon as the cathode. To enhance performance, aerogels—among the world’s lightest solid materials—are ideal candidates for cathodes. Resorcinol-formaldehyde (RF)-based carbon aerogels, for example, serve this purpose well. In my work, I utilized two types of carbon aerogels as cathode materials: one derived from pyrolyzed resorcinol-formaldehyde polymer and the other a graphene-oxide-modified version of this carbon gel. I integrated the carbon aerogels I had pyrolyzed into lithium-air batteries to improve the cell’s performance, energy density, and capacity compared to cells using activated carbon. In my research, I examined the pore structure and surface properties of these materials in aqueous media using NMR (nuclear magnetic resonance) relaxometry and cryoporometry, exploring their impact on battery efficiency. I found that the graphene-oxide-containing sample's pores filled with water in a layered manner, indicating a more hydrophilic surface, which suggests a denser arrangement of oxygen-containing functional groups compared to the unmodified carbon aerogel. The pore sizes were reduced after adding graphene oxide, resulting in an increased specific surface area for the sample. Incorporating the reduced graphene-oxide-containing carbon aerogel enabled the creation of a more efficient, higher-capacity battery than with the RF carbon aerogel. This improved performance is likely due to the aerogel’s higher oxygen content and altered morphology. The increased oxygen content provides more active sites for oxygen reduction, meaning that a greater specific power output can be obtained from the battery.
Evaluation of the Effect of Different Nutrients' Concentration and Composition on Hydroponically Grown Plant
As the world population grows, the demand of food products grows as well and there will be an expected food crisis in the coming years. To prevent those crises, alternative food farming methods must be used. This paper studied two farming systems in different conditions, to compare and find the best, natural and cost-effective system that will cover the current and future demand. The system which can also be used in those areas where soil is less cultivated with insufficient aeration. The first system is the soil-based system (traditional), and the other is hydroponic system. Hydroponic is a technique of growing plants in nutrient solutions with or without the use of an inert medium. Two types of seeds; peas and spinach were observed in both systems over a period of 25 days. In hydroponic plants coco peat was used in place of soil along with the Aegis nutrient. 8 plants were seeded for both types of plants in different systems, conditions, concentrations and pH to conclude the best condition. Growth parameters of all plants including root, shoot and leaf length were observed and recorded daily. On the uprooting, their weight (g), no. of root hairs and used nutrient’s volume(ml) were also recorded. Fungus and insects were seen in the soil plants. The results executed that the growth was maximum in spinach having normal manufacturer nutrient’s spray concentration(1.25ml/625ml) with pH 6 and in peas having normal supplier concentration (5ml/625ml) with pH 4. So, it can be concluded that hydroponic spinach, which is a green leafy plant, can ideally grow at the pH of 6 and peas in slightly acidic condition. Hydroponic planting system has a better growth effect than traditional soil system and this system don’t need any fertilizer, insecticide, pesticide, fungicide and herbicide. While soil plants’ growth was adversely affected by fungus and insects in the absence of these chemicals which can contaminate our food and make it less hygienic for our health. This result achieves the aim of this paper which is finding a planting system and its conditions that can increase the productivity to cover the food demand.