Fuel cells, which have been used to power green car, are a clean source of electricity. They produce power through an electrochemical reaction of hydrogen with oxygen, generating heat and water as by-products.
By Holly Chik
Scientists in China and Australia have developed a catalyst which uses urea-loaded waste water to efficiently generate clean energy, paving the way for low-cost portable fuel cells that work like batteries.
Fuel cells, which have been used to power green car, are a clean source of electricity. They produce power through an electrochemical reaction of hydrogen with oxygen, generating heat and water as by-products.
The new technique oxidises urea – an abundant substance in human and animal urine which is also found in factory waste water. The researchers found they could speed up the process of obtaining hydrogen from water and use it to power fuel cells.
The technique also reduces the amount of urea in waste water, which otherwise could break down into ammonia and cause acid rain if released into the environment without treatment.
The researchers, from Anhui University, the University of Science and Technology of China, and the University of Adelaide in Australia, published their findings in the peer-reviewed journal Nature Energy on Monday.
“It requires less energy and could also reduce the urea content of waste water. This work opens a new avenue to develop alternative electrocatalysts for urea oxidation reactions with a boosted activity and stability,” they wrote.
Co-author Chen Ping, a professor at Anhui University’s school of materials science and engineering, said the technique could be applied anywhere human and animal urine can be collected.
“Our goal is to make human and animal urine and industrial waste water the source of urea. That way we can turn waste into energy. It would be meaningless if we manufactured urea at a high cost to generate energy,” he said.
In the study, the researchers tested the catalyst using simulated urine that mimics the urea levels in human urine and its complex composition. The researchers found the urea accelerated the process of extracting hydrogen from water, reducing energy input and producing more hydrogen than existing catalysts.
China aims to have 1 million fuel cell vehicles on the road by 2030, served by 1,000 refuelling stations around the country, according to a road map published in 2016 by an advisory committee from the Society of Automotive Engineers of China.
A projection by industry guild the China Hydrogen Alliance suggests fuel cells could make up 10 per cent of the country’s energy consumption by 2050. And in June, Shanghai said it expected to have 10,000 hydrogen-powered cars on its roads and 100 hydrogen refuelling stations built by 2023.
Other cities like Beijing and Shenzhen have also planned for the development of hydrogen-powered vehicles, following President Xi Jinping’s pledge to make the country carbon neutral by 2060.
Originally published at South China morning post