▎ 摘　　要

Graphene-Si solar cells have the potential to become low-cost, high-efficiency photovoltaics owing to simplified manufacturing process and compatible integration of two-dimensional graphene with Si wafers. Here, we present an effective way to improve the solar cell performance by introducing carbon nanotubes (CNT) into graphene, a structure called CNT-embroidered graphene (CeG) film, and achieved a power conversion efficiency of 15.2% under standard illumination conditions, which is the highest efficiency for graphene-involved Si solar cell reported so far. The bi-continuous structure consisting of an interconnected CNT spider-web uniformly embedded in graphene film is the material-related factor for improvement, while the co-existence of both graphene-Si and CNT-Si junctions is distinct from previous solar cells based on only one of these junctions. The stability of our CeG-Si solar cells in air storage or chemical doping has been studied, in which the influence of oxide growth and a linear relationship between the Schottky barrier height and open-circuit voltage have been experimentally observed. (C) 2015 Elsevier Ltd. All rights reserved.