Tuesday, June 24, 2008

US Patent 7389671 - Ultrafast palladium nanocluster sensor


Hydrogen sensor are an important component in many fuel cell and internal combustion engine designs but can suffer from slow response times ranging from seconds to minutes. This patent teaches the use of palladium nanoclustors formed on a low stiction interface material (siloxane) to form a more high speed reaction time for hydrogen sensing. Claim 1 reads:

1. A hydrogen detector, comprising:

a non-conducting substrate having mobile Pd or Pd alloy nanoclusters forming a film on said substrate, said film being on the threshold of percolation;

a mechanism electrically connected to said Pd or Pd alloy film for sensing a change in electrical resistance in response to the presence of hydrogen in contact with said Pd or Pd alloy film;

whereby as hydrogen is absorbed by said Pd or Pd alloy nanoclusters they swell resulting in an increase in the conductivity thereof and wherein said non-conducting substrate has a stiction-reducing coating thereon.