Potential huge energy savings through nanocatalysts for nitrogen fixation

A fundamental component of protein, nitrogen is the most common pure element on Earth, making up nearly 80 percent of our atmosphere. Yet despite its abundance, atmospheric nitrogen cannot enter the food chain without first being converted into a form that can be used by plants.

In modern agriculture, the tried-and-true way to do this is to turn nitrogen into ammonia. In 2018, the UN Food and Agriculture Organization expects global demand for ammonia for fertilizers will exceed 115 million tonnes. Meeting that demand relies on a process that uses a great deal of heat and pressure to coerce extremely stable nitrogen molecules to split apart and bond with hydrogen – so much heat and pressure, in fact, that this single industrial process chews up nearly 2 percent of the world’s total energy output.

Imagine a catalyst that could replace this energy-intensive, century-old process with one driven by sunlight at room temperature. Bridging the disciplines of green chemistry and nanoelectronics, McGill University professor Chao-Jun Li and adjunct professor Zetian Mi have succeeded in using III-nitride semiconductor technology to develop a nanocatalyst to synthesize ammonia from nitrogen at ambient temperature and pressure.

“Currently, the reaction works well with UV light,” Li says. “The main obstacle is how to use the entire solar spectrum and to increase the rate of the reaction to practical applications.”

Together with McGill physics professor Hong Guo, Li and Mi have been awarded an MSSI Ideas Fund grant to support further theoretical and experimental work on finding a way past this obstacle.

About the MSSI Ideas Fund

The MSSI Ideas Fund provides small amounts of seed funding to enable faculty and students alike to explore bold projects and novel ideas which, if successful, could make a significant impact on sustainability. The funding allows recipients to explore the feasibility of ideas before dedicating significant resources to flesh them out.

› Learn more about the McGill Sustainability Systems Initiative (MSSI)