 This is where the concept of using sunlight for all of our energy needs comes in, made possible by artificial photosynthesis enabling humans to mimic nature's billion-year-old method of sustaining life. Photosynthesis is the process by which light is converted into chemical energy in plants. It involves breaking water to release oxygen and converting carbon dioxide to glucose. Similarly, the "artificial leaf," a biomimicry device that produces energy from sunlight, water, and carbon dioxide, is at the center of artificial photosynthesis. In contrast to natural leaves, which use sunlight to convert carbon dioxide and water into oxygen and glucose, artificial leaves produce clean fuels like methanol instead of glucose. Through this method, greenhouse gases are effectively converted into green energy while also producing renewable energy. Similar to chlorophyll in actual leaves, the artificial leaves work using semiconductor catalysts that absorb light and produce electron-hole pairs, which are small particles required for the release of light's energy. The semiconductor catalysts are the chemical reactions' accelerators. They ensure that everything moves along swiftly and effectively. Materials such as silicon, titanium dioxide, and gallium arsenide play important role in a photoelectrochemical pathway that splits water. These semiconducting materials capture sunlight and use it to create electron-hole pairs that convert light into energy. The process is then divided into two set of reactions: oxidation and reduction. During oxidation, holes in the semiconductor capture water molecules and break them apart releasing oxygen into the air, similar to how leaves release oxygen. Meanwhile, during reduction, the electrons work on carbon dioxide, converting it into useful fuels such as methanol. This is recycling, which also converts carbon dioxide into important carbonaceous fuels, and thus greenhouse gases to green energy. To maximise their performance, these materials have to undergo sophisticated improvements. Nanostructuring increases the active surface area of the semiconductors, allowing them to absorb light more efficiently. Other modifications, such as doping or creating heterojunctions (joining different materials together), help maintain the energy of the captured electrons longer, ensuring more sunlight is converted into energy. Globally, artificial photosynthesis holds tremendous potential. A study by The National Academy of Science and Engineering estimates that implementing this technology on a large scale, such as across all agricultural land in Germany, could capture around 1,200 billion kWh annually making nearly 30% of the country's total primary energy consumption. In subtropical countries such as India, adopting artificial photosynthesis could significantly shift the energy landscape. This alteration is going to exploit a very valuable natural resource, besides cutting the nation’s reliance on imported non-renewable energy sources, and thereby prepare for a more eco-friendly and sustainable future. At the lead of this shift are big players in the market like Reliance Industries and Indian Oil Corporation which are spearheading the National Hydrogen Energy Mission. The move is part of broader attempts to adopt hydrogen fuel used primarily in oil refining and chemical industries, now as efficient green fuel in energy and transportation sectors. Following this national initiative, many academic institutions in India are contributing to the development of hydrogen fuel technologies. The scientific progression of this domain is also being pushed by distinguished R&D establishments with the assistance of government policies aligning India as a major global player in energy. The Indian Institute of Science has recently developed a technology that is capable of converting sunlight into chemical energy more efficiently than natural photosynthesis. This is significant because it represents a key step in the potentiality of solar conversion. Another team working at The Jawaharlal Nehru Center for Advanced Scientific Research created a system that takes carbon dioxide out of the air and then turns it into carbon monoxide by using sunlight. Their invention not only helps lower levels of CO2 but recycles it as useful chemicals, too. Further contributions from India include work by scientists at IISER-Thiruvananthapuram and IIT-Indore, who have documented enhanced efficiencies for solar energy conversions in prestigious scientific journals, highlighting India's proactive role in pushing the boundaries of sustainable technology globally. However, the road to widespread adoption of artificial photosynthesis in India is not free of hurdles. The selection and development of suitable materials remain a significant problem with issues such as cost, availability, and performance under real-world conditions needing resolution. For instance, the cost per watt for Organo-photovoltaics to run water splitting electrolysis has decreased from over $5 to around $0.50 in the last decade, primarily due to improvements in material efficiency and production processes. However, achieving broader market penetration requires that these costs be reduced further, ideally below $0.30 per watt. Scalability is another key challenge; translating laboratory successes into commercially viable solutions requires overcoming substantial technological and economic hurdles. Additionally, the necessary infrastructure needed to support the broad use of artificial photosynthesis such as facilities for safe and efficient production, storage, and transportation of solar fuels is complex and expensive to implement. Despite these technological and infrastructural challenges, the strides made by Indian researchers and institutions promote a dynamic shift towards sustainable energy. As these technologies evolve and scale, the promise of a cleaner, greener future seems clearer than ever, propelling India closer to achieving its ambitious energy and environmental goals. The latest breakthroughs by Indian researchers in developing an efficient artificial light-harvesting system align seamlessly with the National Green Hydrogen Mission, which India's Union Cabinet has supported with nearly Rs 20,000 crore. This advancement has the potential to lower the production costs of green hydrogen, making it a more viable alternative fuel. The success of this technology could catalyse India's transition to renewable energy, boosting its ability to meet energy demands domestically and possibly through exports, thereby supporting its goal to achieve net zero carbon emissions by 2070.Niharika Gupta, Shruti Laddha, Yuvna Jain, Dhruv Menon are B.Tech students at Plaksha University, Mohali. The Promise of Artificial Photosynthesis: India's Sustainable Energy Vision | MorungExpress | morungexpress.com |
