Nanowire-based solar cells opened a new avenue for increasing conversion efficiency and rationalizing material use by growing different III-V materials on silicon substrates. Here, we propose a multiterminal nanowire solar cell design with a theoretical conversion efficiency of 48.3% utilizing an efficient lateral spectrum splitting between three different III-V material nanowire arrays grown on a flat silicon substrate. This allows choosing an ideal material combination to achieve the proper spectrum splitting as well as fabrication feasibility. The high efficiency is possible due to an enhanced absorption cross-section of standing nanowires and optimization of the geometric parameters. Furthermore, we propose a multiterminal contacting scheme that can be fabricated with a technology close to standard CMOS. As an alternative we also consider a single power source with a module level voltage matching. These new concepts open avenues for next-generation solar cells for terrestrial and space applications.
Christophe Ballif, Aïcha Hessler-Wyser, Antonin Faes, Jacques Levrat, Umang Bhupatrai Desai, Gianluca Cattaneo, Fahradin Mujovi, Matthieu Despeisse
Michael Graetzel, Shaik Mohammed Zakeeruddin, Felix Thomas Eickemeyer, Peng Wang, Ming Ren