Conversion of Laboratory Waste Glass into Useful Micro and Nano Materials for Energy Storage Application

To meet the primary human needs, the use of fossil fuels has increased, ultimately contributing to the rapid depletion of energy. The shortage in the supply of fossil fuels has triggered a huge demand for alternative sources of energy and services associated with it to meet economic and social development. Thus, a plethora of research is being conducted to develop renewable, cleaner, and sustainable energy sources to address global warming and pollution. Various studies on energy conversion (fuel cells) and energy storage (Li-ion batteries) have captivated interest in minimizing dependence on fossil fuels. Hydrogen has been deemed a promising energy carrier for fuel cells instead of fossil fuels. Moreover, it is environmentally friendly and regenerative. The gravimetric and volumetric density of hydrogen in a storage material is crucial for both mobile and stationary applications. Till date, several storage techniques like gas, liquid, and solid have been studied. However, compared to the requirement of high-pressure gas cylinders for compressed hydrogen gas and cryogenic tanks to store liquid hydrogen, the storage of hydrogen in solid materials has been considered much more feasible. Hollow Glass Microspheres (HGMs) have been considered a promising material with several advantageous properties compared to other techniques. The storage capacity of hydrogen in HGMs is ̴ 100 MPa. These HGMs can be produced via cost-effective raw materials like glass cullet and low energy consumption. Similarly, rechargeable Li-ion batteries have also gained much attention as a next-generation energy storage device due to their wide applications in electric vehicles and portable electronic devices. Much effort is devoted to replacing the commercialized graphite anode to increase the Li-storage capacity. Silicon as an anode material has been considered to outperform the traditional material in Li-ion batteries. Several nanostructures of Si, including nanoparticles, nanowires, nanosheets, and nano hollows, can be fabricated via various sources and methods. In this chapter, waste glasses are one kind that can be used as a source to produce both hollow glass microspheres and Si nanomaterial. Despite several recycling programs, billions of waste glasses get dumped in landfills. In India, only 45% of glass waste gets recycled, and the rest end up in landfills every year. As glass does not decompose quickly, proper recycling is necessary and can also reduce the space in landfills. The laboratory glassware mainly comprises tempered borosilicate or soda-lime glass, which is not further recycled beneficially. Therefore, an effort should be made to recycle the waste laboratory glassware and produce some efficient materials which can be incorporated in numerous ways.