Gate-tunable Schottky junction solar cells (SJSCs) based on graphene and graphene mesh electrodes on n-type Si are fabricated and the effect of the external gate voltage (Vg) on the photovoltaic characteristics is investigated. The power conversion efficiencies (PCEs) of both devices continuously increase with increasing absolute values of Vg. Importantly, despite the slightly lower PCE values at Vg = 0 V, the graphene mesh on Si SJSC shows more rapid enhancement of PCE values, from 5.7% to 8.1%, with Vg varied from 0 V to −1 V. The finite element simulation highlights the benefits of the graphene mesh electrodes from the non-uniform and dynamic modulation of potential distributions driven correlatively by a work function change in the graphene regions and electric-field penetration through the hole regions.
ASJC Scopus subject areas
- Materials Chemistry