Environmentally benign novel green pigments: Pr<inf>1-x</inf>Ca <inf>x</inf>PO<inf>4</inf> (x = 0-0.4)

Rare earth based materials have recently attracted considerable attention as potential eco-friendly colourants for low temperature as well as high temperature applications. In the present study, we have synthesized a series of Ca-doped PrPO4 compounds with the general formula, Pr 1-xCaxPO4 (x = 0-0-4 in steps of 0-1) and characterized the compounds by powder X-ray diffraction. All the compositions show a monoclinic monazite structure. The optical properties of the brilliantly coloured pigments [L (brightness), a* (+ red - green), b* (+ yellow - blue)] have been examined. These materials can find application as potential green colourants. © Indian Academy of Sciences.