Inclusion of metal nanoparticles at the core-shell interface of GaAs0.99Bi0.01/ZnO/ITO core-shell nanowire solar cell for photovoltaic performance enhancement

Abstract Optoelectronic performance analysis of perpendicularly aligned conformally coated GaAs 0.99 Bi 0.01 /ZnO/ITO core–shell nanowire solar cell having a core length of 1 μ m, core diameter of 160 nm, shell thickness of 10 nm and period of 280 nm, decorated with Au metal nanoparticles(MNPs) of variable diameters at the core–shell interface is done employing FDTD method. Diameter optimization of MNPs with four different diameters values around core GaAs 0.99 Bi 0.01 nanowire is accomplished in terms of maximum short circuit current density (J sc ), which offered an optimized diameter combination of D 1 = D 2 = 50 nm and D 3 = 34 nm, D 4 = 10 nm, resulting in a maximum J sc of 32.6 mA cm −2 . A detailed analysis of the electric field profile including its top view and longitudinal view is presented to investigate the distribution of electric field upon optical illumination at different wavelength range. The overall photo generation rate profile is also presented to focus on the localized surface plasmon resonance effect caused by the metal nanoparticles (MNPs). In order to boost the electrical performance, a thin coating of electron selective ZnO shell is used around p type GaAs 0.99 Bi 0.01 core, which aids in charge carrier separation, thereby improving open circuit voltage (V oc ) and overall power conversion efficiency (PCE). The electrical characteristics of bare NW and MNP decorated GaAs 0.99 Bi 0.01 /ZnO core–shell nanowire solar cell for different MNP diameters have been compared. For the optimized diameter combination, as stated above, a V oc of 941 mV, J sc of 28 mA cm −2 , FF of 84.35% and PCE of 22.19% is obtained for SRV of 10 5 cm s −1 at the interfaces and SRH recombination lifetime as less as 10 ns. For SRV of 10 5 cm s −1 at the interfaces and SRH recombination lifetime of 1 μ s, this proposed structure can achieve a V oc of 1.06 V, J sc of 31.5 mA cm −2 , PCE of 29.37% and FF of 87.88% for equal diameters of D 1 = D 2 = D 3 = D 4 = 50 nm.