Zirconium phosphate-based porous heterostructures: A new class of materials for ammonia sensing

Metal(IV) phosphates such as zirconium phosphate (ZrP) are well known proton conductors based on the mobility of protons localized at Brønsted-acid sites. By introduction of mesoporous silica into the interlayer region, these compact materials are transformed into Porous Phosphate Heterostructures (PPH). Here we studied the electrical properties of PPH and show that the proton conductivity is supported by ammonia, which does not occur neither in ZrP nor in the mesoporous silica. This demonstrates that transforming the layer structure of ZrP into a mesoporous hybrid material leads to a new ammonia gas sensing material. This concept might be promising for the development of new gas sensor materials in general.