Solar Fuel Generation Technology

As the search for renewable sources of energy grows more urgent, more and more attention is focusing on the blueprint offered by biological photosynthesis for translating the energy of our Sun into energy rich molecules like H₂ and hydrocarbons, commonly known as "solar fuels." These solar fuels have enormous potential to store high densities of energy in the form of chemical bonds as well as being transportable. This technology is based on the inexpensive photocatalytic materials to generate  hydrogen using solar radiation with improved efficiency, stability.

Driven by the ever-growing demand for energy and the rising atmospheric CO₂ level, there is a thriving interest to tap renewable energy sources. The Sun supplies about 7,000 times more energy than the total energy demand on the Earth. Only a very small fraction of abundantly available solar energy is consumed by biological photosynthetic processes to be stored as biomass (carbohydrates and oils) that can be used as fuels. The development of technologies that can capture solar energy and convert and store it in usable form on a massive scale (greater than what is available with existing technologies) is highly desired for a long-term solution to meet the ever-increasing energy demand. Biological photosynthesis provides a blueprint to translate solar energy into energy-rich molecules (such as H₂ and carbohydrates), commonly known as solar fuels. These solar fuels have enormous potential to store a high density of energy in the form of chemical bonds that are transportable. We at IMMT have been engaged to mimic photosynthesis and developing the understanding about the tricks/concepts that are crucial in designing efficient photocatalytic systems to efficiently generate H₂ and convert CO₂ to energy rich compounds.

CURRENT STATUS:

• A hetero-structured photocatalyst based system has been developed which show the the photocurrent density 7 mA cm^-2 (many folds higher than that of reported in literature for any niobate photocatalyst) and ~12,000 µmol g^-1 h^-1 H₂ generation rate. (TRL LEVEL-4/5)
• An inexpensive carbon based photocatalyst system has been developed which show the H₂ generation rate of the order of ~21,000 µmol g^-1 h^-1. (TRL LEVEL-4)

Some of the impacts of this technology under various perspective are mentioned below:

Socio-Economic Impact:  An alternate energy generation process/device.

Technology /S&T Gap: Carbon neutral alternative energy generation. There is no scalable process for solar H₂ generation available in India and abroad.

Environment Conservation: Carbon neutral energy generation process.