It is well-known that the conventional supported catalyst powders usually suffer from a large flow resistance, and the poor heat transfer through the powders will easily lead to unacceptably non-uniform temperature distributions.However, the structured catalyst have smaller characteristic lengths, larger surface to volume ratio, and more compact size, and therefore have the advantages of intensified heat and mass transfer, improved reaction efficiency, and ease of use in portable applications.Typical examples include the microreactors [1], mieorfibrous composites bed [2] reactor and monolith structured reactor [3], which supported Ru or Ni catalysts exhibiting good activity for ammonia decomposition.