Analysis of the Definitions Related to Catalyst

: After first established in 1835, the definition of catalyst has undergone several progresses. In 1996, IUPAC Nomenclature Committee proposed a new definition of catalyst. But till now this new definition has not been adopted extensively. In this paper, the fundamental characteristics of catalyst are listed and discussed with the essential features being clarified. Based on these discussion, a new definition of catalyst is suggested. The concept of negative catalyst is analyzed based on the essential features of catalyst. It is suggested to replace negative catalyst by inhibitor. It is meaningful for us to get a better understanding of catalyst and correct misunderstandings in the present physical chemistry textbooks.