Green Nanotechnology in Solar cells by Rani Jarkas

Green nanotechnology is the development of clean technologies, “to minimize potential environmental and human health risks associated with the manufacture and use of nanotechnology products, and to encourage replacement of existing products with new nano-products that are more environmentally friendly throughout their lifecycle” As the growing needs to protect our environment are increasing, many scientists are looking into ways to develop clean, affordable, and renewable energy sources, with a smaller environmental footprint and minimise pollution.

Solar Panels

One major project that is being worked on is the development of nanotechnology in solar cells. Solar cells are more efficient as they get tinier and solar energy is a renewable resource. A group of researchers are making solar power significantly more efficient by scooping up more of that wasted energy.

Researchers at Stanford University have found a way to trap light in organic solar cells. The idea is that the longer light is in the solar cell the more electrons will be generated. The researchers found that by making the organic layer much thinner than the wavelength of light and sandwiching the organic layer between a mirror layer and a rough layer the light stayed in the solar cell longer and excited more electrons.

Researchers at Michigan Technological University have developed a honeycomb like structure of graphene in which the graphene sheets are held apart by lithium carbonate. They have used this “3D graphene” to replace the platinum in a dye sensitized solar cell and achieved 7.8 percent conversion of sunlight to electricity.

Researchers at Los Alamos National Lab have demonstrated a solar cell that uses a copper indium selenide sulfide quantum dots. Unlike quantum dots containing lead or cadmium the copper based quantum dot is non-toxic as well as low cost.

A field emission scanning electron microscopy (FESEM) image of 3D honeycomb-structured graphene. [ranijarkas.wordpress.com]

MIT researchers have made major strides toward developing solar cells that are inexpensive, efficient, flexible, and transparent using a design that combines two special components: nanowires and graphene. Tests with assembled solar cells showed that incorporating the nanowires pushed up device efficiency and that there was no performance penalty for replacing a conventional high-cost, brittle electrode with their version made of abundant, inexpensive carbon.

Rani Jarkas, the Chairman of Cedrus Investments.

Rani Jarkas is a highly experienced financial services executive, with over 20 years of international banking experience. Currently, Mr. Jarkas is the Chairman of Cedrus Investments, a global boutique investment firm. Cedrus’ domain expertise is in life sciences, natural resources, energy, cleantech and nanotechnology. – Rani Jarkas