Filing Date: 2006-12-08.-- Priority Data: US 60/748,340 (2005-12-08)A catalytic material includes a metal oxide catalyst anchored to a nano-sized metal oxide crystal as support and functions well at low temperatures. The catalytic material may optionally include another metal oxide as promoter deposited on the surface of the support to modify the properties of the metal oxide catalyst and/or the properties of the support. The catalyst may be vanadium oxide, tungsten oxide, manganese oxide, chromium oxide or molybdenum oxide; the support may be TiO 2 , SiO 2 , Al2O 3 , ZrO 2 , or WO 3 ; and the promoter may be vanadium oxide, tungsten oxide, manganese oxide, chromium oxide or molybdenum oxide. A method of preparing the catalytic material comprises: depositing a metal catalyst precursor on the surface of the metal oxide support; converting the metal catalyst precursor to active metal oxide catalyst; and removing excessive hydroxyl groups from the surface of the support. The catalytic material is useful in removing ammonia and other nitrogen containing contaminants.