Nature is a fascinating mix of processes that work in perfect unison to help sustain life on Earth. And one of these key processes is photosynthesis, which constitutes the basic life-supporting mechanism for almost all life on the planet. Amazingly, scientists can now mimic photosynthesis to create hydrogen fuel which could be a game changer for securing our ever-increasing demand for renewable energy.
The science and other stuff to know
Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar. During the process, water is oxidized, losing electrons, while the carbon dioxide gets reduced, gaining electrons. The process transforms water into oxygen and carbon dioxide into glucose. The oxygen is released back into the air, without which life as we know it cannot exist.
The groundbreaking study published in the Journal of the American Chemical Society discusses how scientists have now found a way to mimic photosynthesis to convert light energy into chemical fuel.
In a joint effort by scientists from Florida State University (FSU) and the University of South Carolina, the researchers combined two molecules, a photoredox catalyst (i.e., a catalyst that moves electrons with light) and naphthol, a fluorescent organic compound, Phys.org reported.
The molecules were then exposed to light, enabling each to absorb a photon and generate hydrogen fuel, “mimicking a process referred to as the Z-Scheme in natural photosynthesis”, the paper said.
“One of the holy grails of alternative energy research is to use sunlight to make chemical bonds that can later be used as fuel,” FSU Associate Professor of Chemistry Ken Hanson was quoted by Phys.org as saying. “But making high-energy bonds is hard work and difficult to do with one packet of light energy or a photon.”
South Carolina Associate Professor of Chemistry Aaron Vannucci, who was part of the study team, said the system derived its uniqueness from the molecule “we use for the bond-forming reaction. Remarkably, despite being a simple and abundant molecule, naphthol absorbs light, accepts electrons and acts as the catalyst for hydrogen production”.
Alternative energy is a rapidly advancing field and one on which all climate preservation bets are being hinged. Several industries are experimenting with using alternative energy sources to meet energy demands and offer sustainable solutions. These industries include the automobile sector, where electric cars promise a future where transportation has net zero emissions. Toyota recently announced success with its first-ever hydrogen combustion engine, and others are set to come up with their own novel solutions.
This development could offer researchers additional insights into harnessing the abundant energy of the Sun and lead to subsequent successes down the road.
While the researchers admit that the system’s efficiency is only at 5 percent, it’s definitely a promising start, and achieving economies of scale always takes time. Despite more than a century-and-a-half of innovation behind it, the internal combustion engine, for example, can only still attain a thermal efficiency of roughly 40 percent at max. Improvement is always an ongoing endeavor, and technologies are rarely super efficient right off the bat.
The scientists hope the insights will help them improve the energy conversion efficiency and expand process utility to other reactions.