Getting precious metals out of green energy with catalysts (and putting carbon back in)

From plastics, to pharmaceuticals, to fertilisers, most industrial chemicals are made with catalysts.

Catalysts don’t get consumed in the manufacturing process  – they just make the reactions possible.

But the world is going to need more catalysts as we decarbonise, particularly to use in making hydrogen fuel and capturing carbon.

According to Professor Liming Dai, director of the new ARC Centre of Excellence for Carbon Science and Innovation, and a researcher at the University of New South Wales, to be genuinely sustainable  we’re going to need to update our catalyst science – and get rid of some metals.

Cosmos spoke to Dai at the First Australian Conference on Green and Sustainable Chemistry and Engineering, being held in Cairns this week.

“Now, people use metal-based catalysts, particularly for clean and renewable energy technologies,” he says.

Noble metals (not the same as noble gases), including silver, platinum, palladium and gold, are particularly good catalysts.

These metals are all expensive, and difficult to mine in large quantities.

“Critical minerals, including the noble metals and some precious metals, are concentrated in several countries only. So, due to geopolitical risks, the price of noble metals will increase further,” says Dai.

“So, we need to find cheaper, abundant materials to use in catalysts for many things. That’s why metal-free catalysts can play important roles in clean energy technologies.”

Dai’s research group started working on metal-free catalysts 12 years ago, and has helped spur researchers around the country and the rest of the world to follow suit.

“We opened the metal-free catalyst research field,” he says.

They’ve found particular success with carbon-based materials, many of which have been derived from graphite and carbon nanotubes.

“We found that carbon catalysts are really good to replace platinum, say, for fuel cell technologies to generate clean electricity with hydrogen,” says Dai.

Carbon is abundant on Earth – and there’s flexibility in the feedstocks people can use.

“Carbon catalysts can be made from carbon dioxide, which reduces carbon dioxide emissions,” points out Dai.

They can also be made from biomass and other agricultural sources – even grasses or plants.

The new Centre of Excellence has received $35 million in funding across seven years.

With this funding, Dai is confident they’ll find better chemicals to use in climate change solutions. “We will develop new carbon catalysts for clean energy production and storage without any carbon dioxide emissions, and also, clean production of chemicals to reduce carbon dioxide emissions.”

Ellen Phiddian’s airfare to Cairns was paid by the Royal Australian Chemical Institute, which is managing the First Australian Conference on Green and Sustainable Chemistry and Engineering.