Nature has created the most sophisticated and efficient solar energy conversion system in plants, algae, and a wide variety of photosynthetic bacteria. These photosynthetic organisms use light harvesting antenna protein to capture the sun's energy. This energy is then transferred to a reaction center (RC) where the primary process of charge separation begins. The excited electrons then go through an electron transport chain to make chemical compounds to fuel the organisms' activities. The ability to understand how we could harvest the electrons produced during photosynthesis would help us to better design photovoltaic devices with higher conversion efficiency. The natural biomolecules still possess a plethora of useful functionalities that can be exploited for novel engineering devices. With a prime focus on exploring these functionalities for developing biohybrid devices, we apply cutting edge Materials Engineering approaches in Nanomaterials synthesis and Nanofabrication in conjunction with bio-chemical and genetic engineering principles.
Plants have developed a very complex photosynthetic apparatus over several ages of evolution and the photosynthetic proteins from these plants demand a better understanding of their structure and function for effective application in bio-hybrid devices.
Bacteria have a relatively well understood photosynthetic apparatus with a simple structure and function enabling ready application in a variety of bioelectronic devices. Our research thus is primarily based on exploiting bacterial photosynthetic proteins for bioelectronic and energy storage applications.
We develop new device architectures for bio-electrochemical cells and bio-photovoltaics with tools of nanotechnology, band-gap engineering, bio-chemistry and genetic engineering
The field of artificial photosynthesis has gained a lot of attention in the recent times and is one of the top emerging research technologies listed by the World Economic Forum in 2017. There is now a great quest to learn from nature’s photosynthetic apparatus in meeting our future energy needs. This field holds a huge potential for the future society and most popularly, in 2015, Bill Gates described it have a “magical” potential. There are two promising directions of research in Artificial Photosynthesis; one is to mimic the structure and function of a natural photosynthetic system in fully man-made synthetic systems and the other is to develop semi-artificial or bio-artificial systems that combine natural photosynthetic proteins with engineered electronic and electrochemical material systems in a hybrid device.
With the aim of realizing sustainable and autonomous solar water splitting, we develop hybrid artificial photosynthetic systems for photocatalytic hydrogen evolution and CO2 reduction with the use of natural and synthetic photocatalysts
Energy storage is one of the actively-researched areas both in academia and in industry and developments in the field hold a great commercial value. Besides improving the device performance in batteries and capacitors, there is now a need to tune the devices to meet the demands on the growing electronics industry. We develop energy storage devices with more robust and sustainable materials for use in flexible and wearable electronics.
Rather than electrically charging the devices, the concept of directly charging energy-storage devices with solar light energy is also emerging with huge promises for modern electronics. As opposed to many recent efforts on supercapacitors and batteries charged by solar cells in a hybrid system, we work on developing a single integral material-system that possesses the capabilities of a solar cell and a battery put together (i.e. light harvesting, charge separation and charge storage). Photosynthesis offers great inspirations in developing such models.
Low intensity indoor lightings are often wasted and unutilized, when they could be harvested to produce electrical energy. Unfortunately, there is currently no solar cells which could harvest low light intensity efficiently.
We develop novel materials and systems that aid in harvesting energy from low-light ambience. Photovolatic devices developed with energy transfer redox couples (ETRCs) make use of Forster Resonance Energy Transfer (FRET) between an electrolyte-donor and a dye-acceptor. With this approach photovoltaic efficiency 28% higher than that in the conventional silicon solar cells could be achieved under low light intensity.
Scavenging ambient energy sources in the environment to meet human energy demands either partly or fully has gained impetus in recent years to promote a sustainable society. Ambient energy sources typically include solar energy, thermal energy, air flow, mechanical movements/vibrations, electromagnetic fields, and radio waves. We develop new approaches in scavenging ambient energy to generate electrical energy to power devices.
A rather overlooked ambient source is atmospheric humidity which not only is seen as redundant but also seen as a burden as it demands enormous energy input to keep its levels within thermal comfort. We develop super-hygroscopic electrochemical systems to tap energy from ambient humidity.
