Influence of urea on growth habit and Physicochemical properties of ammonium chloride single crystal

Abstract

The Ammonium chloride (NH₄Cl) has dendritic growth habit. The dendritic growth habit of NH₄Cl was suppressed in the presence of urea. The single crystals with uniform dimensions were harvested using solution growth method by the slow evaporation. The single crystal XRD analysis of urea added NH₄Cl confirms the cubic crystal system and the lattice constant was found to be a = b = c = 3.877 Å and axial angle is α = β = γ = 90°. Purity of the grown crystal in the crystalline phase is shown by the powder XRD. No variation in cell parameter and crystal structure is observed from the results obtained from both single crystal and powder XRD. The presence of functional groups and vibration were confirmed using Fourier transform infrared spectroscopy. UV–Vis-NIR spectrum revealed the transparency of the grown crystal is 85 % and the obtained optical band gap energy of the grown crystal is 3.42 eV. The obtained SHG efficiency from the Kurtz and Perry powder technique is two times higher than KDP crystal. The broad emission from photoluminescence spectrum at 373 nm indicates that, the grown crystal possesses potential for the manufacture of light emitting diodes. The Thermal property of urea added with NH₄Cl molecule shows eutectic melting point at 275 °C. The work hardening coefficient of the grown crystal obtained from microhardness analysis is 1.77. Dielectric behaviour and ac conductivity of urea added NH₄Cl single crystal was studied for the different temperature and frequency and it’s lower activation energy was found that 0.00875 eV at applied frequency 1 kHz. The photoconductivity measurement verified that nature of the crystal was positive photoconductive.