By: Lucy Goodchild van Hilten, Posted on: July 19, 2017

The method overcomes one of the biggest roadblocks to a hydrogen fuel economy

A new, cheaper method of producing hydrogen for fuel cells could help accelerate the energy transition and make it easier for us to move away from the fossil fuel economy. Using the new method, published in Chinese Chemical Letters, researchers have produced high quality hydrogen from methanol at a low temperature and normal atmospheric pressure and without the need for additional chemicals, making it much cheaper than existing methods.

The authors of the study, from Suzhou Institute of Nano-Tech and Nano-Bionics and Shanghai University in China, say their findings are significant for establishing a carbon neutral economy.

Hydrogen has great promise for our future energy needs: it has high energy density, so a small amount produces a lot of energy, it is easy to convert to electrical and mechanical energy, and it produces only water when converted to energy. It is transported as part of other molecules, like methanol, then broken down and released when it’s needed. This means it could be possible to use our existing gas systems for hydrogen in the future, which is an important consideration when looking for large-scale alternatives to fossil fuels.

But so far, all the methods of producing hydrogen from methanol for applications like fuel cells have been prohibitively expensive, because they require high temperatures and pressures, and use additional chemicals. The team behind the new method wanted to find a way of converting methanol to hydrogen without the high cost. They were able to produce high quality hydrogen by breaking down methanol at the low temperature of 70˚C and atmospheric pressure.

“Our global demand for energy is increasing, while our supply of fossil fuel is depleting, so the development of large-scale alternatives to fossil fuel is becoming increasingly important,” said study author Dr. Xiao-Chun Zhou, from Suzhou Institute of Nano-Tech and Nano-Bionics. “Using hydrogen as an energy source in fuel cells has tremendous potential to decrease greenhouse gas emissions, but we first need to lower the cost of producing it.”

The researchers used a homogeneous catalyst – a substance in a solution that helps speed up the reaction – that contains the metal rhodium. They didn’t need any additional alkaline or organic chemicals, which conventional methods need. The gas produced contained no carbon monoxide, which is a common contaminant of hydrogen, so the hydrogen could be used directly in the fuel cell without the need for purification.

The method also works well at 70˚C and atmospheric pressure – much milder conditions than existing methods require. This opens the possibility of using the excess heat produced by the fuel cell itself to convert methanol into hydrogen.

“Fuel cells can transfer chemical energy to electrical energy very efficiently and are already showing promise in cars and many other applications,” said Dr. Zhou. “But the energy source – the hydrogen – is still a big problem. Our new method opens the possibility to produce clean hydrogen using only waste heat of fuel cells to power the reaction, which we think will be significantly beneficial for the further development of fuel cells.”

About the article

“Hydrogen generation from methanol reforming under unprecedented mild conditions,” by Yu-Lu Zhan, Yang-Bin Shen, Shu-Ping Li, Bao-Hua Yue, Xiao-Chun Zhou (https://doi.org/10.1016/j.cclet.2017.03.038). It appears in Chinese Chemical Letters, (In Press), published by Elsevier.

About Chinese Chemical Letters