Nucleation kinetics, growth, mechanical, thermal and optical characterization of sulphamic acid single crystal

Abstract

Sulphamic acid (HSO 3 NH 2 ) is a potential material that exhibits excellent piezoelectric and non-linear optical properties.Nucleation and growth kinetics give valuable information about the crystal growth process, which can be employed in the growth of large size crystals. Thus we have studied its nucleation parameters such as solubility, metastable zone width, induction period, interfacial tension, critical free energy, volume free energy change, critical nucleus and found that good quality sulphamic acid crystal can be grown at low temperature. Growth of good quality crystal was done by adopting slow evaporation solution growth technique at room temperature and as a result, good quality single crystal was grown. The grown bulk single crystal of the title compound was subjected to various characterization analyses. Its unit cell dimensions were confirmed using powder X-ray diffraction. Further its crystalline perfection was assessed using high resolution X-ray diffraction and X-ray topography techniques and it was found that it is reasonably good. Its various functional groups were identified from the Fourier transform-Raman method. Nanoindentation was performed to identify the load dependence and independence of hardness (H) and Young's modulus (E) using the Oliver-Pharr method and it was found that both H and E exhibit peak load dependence. Photopyroelectric study was performed to identify its thermal properties such as thermal diffusivity (α), thermal conductivity (k), thermal effusivity (e), and heat capacity (cp). These studies reveal that it has high thermal stability compared to other single crystals. The optical homogeneity of the grown crystal was assessed using a birefringence interferometer and it was found to be reasonably good.

Growth of a bulk-size single crystal of sulphamic acid by an in-house developed seed rotation solution growth technique and its characterization

“…The FWHM of the curve was found to be $8.0 00 , which is close to that expected for an ideal perfect single crystal as predicted by the plane wave theory of dynamical X-ray diffraction (Batterman & Cole, 1964). It is observed that the FWHM of the SA crystal grown by the SRT technique is less than what is typically achieved via the conventional SEST (Jat et al, 2013). This low value of FWHM indicates that the grown SA crystal possesses good crystalline perfection.…”

“…It is a strong inorganic acid, which is moderately soluble in water (Senthil Pandian et al, 2010). Sulphamic acid forms zwitterions when dissolved in water and possesses outstanding catalytic features which make it different from other acidic catalysts (Jat et al, 2013). Because of these advantages, the Japanese Industrial Standards Committee has considered this reagent as a standard substance for titrimetric analysis (Yoshimori & Tanaka, 1973).…”

Enhancement of thermoelectric figure of merit in Bi2Se3crystals through a necking process

“…This clearly happened owing to significant decrement in the hardness of the title compound with increase in the load. The increasing value of the contact depth h c can also be correlated with the indentation size d. Thus we have a relation between peak load and contact depth as (Jat et al, 2013) …”

“…13(c), the dependence of the stiffness on the contact depth can be observed. The relation of S with h c is given as (Jat et al, 2013) …”

“…We maintained a constant loading and unloading speed of 20 mN min À1 throughout the measurement, having a dwell time of 10 s between the loading and the unloading step. Using the Oliver and Pharr standard method (Jat et al, 2013), nine indentations were made on the cleaved surface of the bismuth selenide crystal.…”