Chinese scientists have developed membranes that could improve direct methanol fuel cells (DMFCs). DMFCs oxidise methanol to produce small amounts of electricity over long periods, making them ideal as portable power supplies. A vital component of DMFCs is the membrane, which separates the two reactions of the cell while allowing protons to move between them. But sometimes unreacted methanol can also pass through the membrane, which reduces the fuel efficiency and performance. 'This methanol cross-over is an Achilles' heel for the implementation of the DMFC,' says Yohannes Kiros, an expert in fuel cells and energy at the Royal Institute of Technology,...