Fossil fuels cause environmental deterioration is not anything new, and for this many scientists world over are focused on finding efficient alternatives. Hydrogen fuel cells have emerged as an alternative high hopes bank on, however, the storing, transporting, and huge cost associated with hydrogen deters their feasibility. In contrast, methanol – a type of alcohol – is easier to transport, does not require cold storage, and possesses higher energy density. With such benefits, transition to a methanol-based economy is a more viable goal.
Methanol fuel cells associated with ambient shortcomings
However, it requires direct methanol fuel cell at room temperature to generate electricity. And, sadly, direct methanol fuel cell offers subpar performance. In fact, one of the main problems in direct methanol fuel cells is undesired methanol oxidation reaction, when it passes from the anode to the cathode. This reaction causes degradation of the platinum catalyst that is essential for the operation of the cell. While a number of strategies to alleviate this problem have been suggested, so far, none has been good enough due to stability or cost issues.
A recent study carried out by a team of scientists is published in ACS Applied Materials & Interfaces. Using a relatively simple procedure, the team created a catalyst composed of Pt nanoparticles capsuled within a carbon shell. This shell builds an almost impenetrable carbon network with small apertures caused by nitrogen defects. Although oxygen – one of the key reactants in direct methanol fuel cell – can outreach the Pt catalyst through these holes, methanol molecules are big in size to pass through. In fact, the carbon shell works as a molecular sieve and selectively allows molecules to pass through toward the desired reactants, for them to land on the catalyst sites.