Effect of EDTA on the growth kinetics, structural, optical and mechanical properties of ADP crystal

Abstract

The pure ammonium dihydrogen phosphate (ADP) and ethylenediamine tetra acetic acid (EDTA) added ADP crystals were grown by isothermal evaporation method. The solubility of ADP was determined for five different temperatures. Metastable zone width of aqueous solutions of ADP saturated at different temperatures was determined by nucleation method in pure form and adding with 0.5 mol.% EDTA. The induction period τ was measured and experiments were performed at selected degrees of supersaturation (C/C*) and the critical nucleation parameters like interfacial energy (σ), energy of formation of the critical nucleus (ΔG*) were calculated based on the classical theory of nucleation. The grown crystals have been subjected to study the structural, optical and mechanical properties. FTIR analysis has been carried out to characterize the grown crystals. The transmission spectra from (100) planes of the grown crystals show that the transmission increases from 55.86 to 83.23% due to addition of EDTA in the visible region and band gap was found to increase from 1.31 to 1.41 eV. The microhardness test was carried out on (100) plane. The load dependent hardness and work hardening coefficient were measured.