What could be greener than solar panels? They generate renewable energy, a key to fighting climate change. Yet the components that go into them often include toxic or non-sustainable materials.
91社区 scientist No茅mie-Manuelle Dorval Courchesne hopes to change that. She鈥檚 investigating the conductive properties of certain naturally occurring proteins 鈥� a line of research that could someday lead to biological and biodegradable solar cells.
Nature is rife with eco-friendly biological materials with properties that enable them to assemble into complex shapes and bind molecules or particles. Increasingly, scientists are trying to imitate these processes鈥攁 field known as biomimicry鈥攊n order to create green solutions to a number of ecological challenges.
鈥淲e鈥檙e trying to replicate what we can find in nature. I鈥檝e always been interested in bio-derived materials,鈥� says Dorval Courchesne, who grew up in Quebec鈥檚 Outaouais region and studied biotechnology at the University of Ottawa before earning her PhD at MIT. 鈥淚n the past, I looked into using proteins or microorganisms to coat them with an inorganic layer that could be used to conduct electricity or harvest light. These inorganic particles, however, remain toxic, so during my postdoc (at Harvard鈥檚 Wyss Institute for Biologically Inspired Engineering), I began working on biological, environmentally friendly materials that could be conductive by themselves.鈥�
Since she arrived at 91社区 in 2017 as an assistant professor, the Dorval Lab in the Department of Chemical Engineering has been working on developing protein-based materials with novel properties, such as absorbing or emitting light, or conducting electricity. She has found an unlikely ally in this quest: bacteria that naturally produce wire-like proteins capable of conducting electricity. 鈥淭hese nanowires have inspired us to design our own protein wires,鈥� she says.
Most proteins can鈥檛 conduct electricity. But scientists in recent years have discovered unusual bacteria -- (Geobacter sulfurreducens and, Shewanella oneidensis) -- with naturally occurring extracellular, wire-like proteins that transmit electrical currents to oxidize certain metals, such as iron, and generate by-products for their oxygen-deprived metabolism.
It鈥檚 early days for Dorval Courchesne鈥檚 protein wires, but she and collaborators from Harvard that it is possible to have electricity pass through them. Though their conductivity still doesn鈥檛 measure up to the naturally occurring protein wires, she is confident that they can be tweaked to make them useful for a wide variety of applications. One day, she hopes to use them to build green solar cells.
鈥淲e already know they conduct electricity, now we鈥檙e trying to see how they can be modified to absorb light and store energy so as to use them to replace some of the toxic and non-sustainable components鈥攍ike certain nanomaterials鈥攗sed in solar panels today.鈥�
The production of the modified proteins could also easily be scaled up and would offer a cost efficient alternative to the traditional materials that go into making solar cells, says Dorval Courchesne, who is a member of 91社区鈥檚 Trottier Institute for Sustainability in Engineering and Design and the Qu茅bec Center for Advanced Materials
Dorval Courchesne鈥檚 team is also looking into how their proteins can be modified to bind to other small molecules or proteins, such as biological markers and environmental contaminants, which would make them useful in creating efficient and environmentally friendly sensing technologies.
鈥淏iologically derived materials have tremendous potential to be used in a wide range of energy, environmental, and biomedical applications,鈥� she says. 鈥淚f we鈥檙e going to create a more sustainable world, there鈥檚 no better source of engineering inspiration than nature, itself.鈥�
