1. Designing Sustainable Catalysts: Catalysts are essential components in many chemical processes, but traditional catalysts often require toxic or non-renewable materials. Researchers are exploring the use of sustainable catalysts, such as enzymes, metal-organic frameworks, and renewable resources, to reduce the environmental impact of chemical reactions.

2. Developing Renewable Fuels: Fossil fuels are a major source of greenhouse gas emissions and contribute to climate change. Researchers are working to develop renewable fuels, such as biofuels from algae, waste, and other sustainable sources, to reduce our dependence on non-renewable resources and decrease carbon emissions.

3. Creating Biodegradable Polymers: Plastics are a major source of pollution and can take hundreds of years to decompose. Scientists are exploring the use of biodegradable polymers, such as polylactic acid (PLA) and polyhydroxyalkanoates (PHAs), as alternatives to traditional plastics.

4. Developing Green Solvents: Many chemical reactions require solvents, which can be toxic, flammable, or harmful to the environment. Researchers are investigating the use of green solvents, such as ionic liquids, supercritical fluids, and water, to reduce the environmental impact of chemical processes.

5. Recycling and Upcycling Waste: Waste is a major environmental issue, but it can also be a valuable resource. Researchers are exploring ways to recycle and upcycle waste materials, such as plastics, textiles, and electronics, to create new products and reduce waste in landfills.