A novel maskless approach towards aligned, density modulated and multi-junction ZnOnanowires for enhanced surface area and light trapping solar cells

Abstract

A maskless method of employing polymer growth inhibitor layers is used to modulate theconflicting parameters of density and alignment of multi-junction nanowires via large-scalelow temperature chemical route. This low temperature chemical route is shown tosynthesize multi-junction nanostructures without compromising the crystal quality at theinterfaces. The final morphology of optimized multi-junctions nanowire arrays canbe demonstrated on various substrates due to substrate independence and lowtemperature processing. Here, we also fabricated devices based on density modulatedmulti-junction nanowires tuned to infiltrate nanoparticles. The fabrication of hierarchicallystructured nanowire/nanoparticles composites presents an advantageous structure,one that allows nanoparticles to provide large surface areas for dye adsorption,whilst the nanowires can enhance the light harvesting, electron transport rate, andalso the mechanical properties of the films. This work can be of great scientificand commercial interest since the technique employed is of low temperature (<90 °C) and economical for large-scale solution processing, much valued in today’s flexible displayand photovoltaic industries.