In this article we report the growth kinetics of ultrafine monodispersed silver nanoparticles prepared via thermal reduction of silver nitrate with oleylamine. Effect of nucleation and growth temperature and time on the quality and quantity of silver nanoparticles was monitored in terms of product yield, crystal phase, morphology, aggregation, particle size and size distribution. To understand the effect of kinetic parameters, purified silver nanoparticles were characterized by UV-visible, FTIR and photon correlation spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM) and thermogravimetry (TG).Irrespective of the kinetic conditions, oleylamine always reduces AgNO 3 into spherical Ag nanoparticles with simple cubic structure. The nanoparticle yield is highest for 21 mM oleylamine. Its size decreases with increasing oleylamine concentration and levels off at 3.5 nm with a polydispersity of 0.12. When concentration of oleylamine is ,15 mM, agglomerated silver nanoparticles resulted while they selfassembled into hexagonal close pack structure when oleylamine is ¢15 mM. Nucleation at 200 uC for 30 min and growth at 150 uC for 4 h are the optimum processing parameters for highest nanoparticle yield (60%), lowest particle size (3.5 nm) and polydispersity index (0.12) with no or very little agglomeration.

Solar cells based on perovskites have emerged as a transpiring technology in the field of photovoltaic. These cells exhibit high power conversion efficiency. The perovskite material is observed to have good absorption in the entire visible spectrum which can be well illustrated by the quantum efficiency curve. In this paper, theoretical analysis has been done through device simulation for designing solar cell based on mixed halide perovskite. Various parameters have efficacy on the solar cell efficiency such as defect density, layer thickness, doping concentration, band offsets, etc. The use of copper oxide as the hole transport material has been analyzed. The analysis divulges that due to its mobility of charge carriers, it can be used as an alternative to spiro-OMeTAD. With the help of simulations, reasonable materials have been employed for the optimal design of solar cell based on perovskite material. With the integration of copper oxide into the solar cell structure, the results obtained are competent enough. The simulations have shown that with the use of copper oxide as hole transport material with mixed halide perovskite as absorber, the power conversion efficiency has improved by 6%. The open circuit voltage has shown an increase of 0.09 V, short circuit current density has increased by 2.32 mA/cm 2 , and improvement in fill factor is 8.75%.

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