Mention the names of four principles of green chemistry.(b) Write advantages of nanoparticles and nanotechnology in the field of energy sector.

Answer:

(a) Any four of: (1) Prevention of waste or by-products, (2) Atom economy, (3) Less hazardous chemical synthesis, (4) Designing safer chemicals, (5) Use of safer solvents and auxiliaries, (6) Design for energy efficiency, (7) Use of renewable feedstock, (8) Reduce derivatives, (9) Use of catalysts, (10) Design for degradation, (11) Real-time analysis for pollution prevention, (12) Inherently safer chemistry for accident prevention.

(b) Energy sector:

• Nanomaterials give batteries and fuel cells of higher capacity, faster charging and longer life.
• Nanostructured materials (e.g. quantum dots, nano-coatings) increase the efficiency and lower the cost of solar cells.
• Nano-catalysts make production of fuels (e.g. hydrogen) and refining more efficient and help in hydrogen storage.
• Lighter and stronger nanocomposites reduce the weight of vehicles, saving fuel; nano-insulation and LED lighting reduce energy losses.