▎ 摘　　要

In the study, the chemically-derived reduced graphene oxide flakes on the pyramidal Si substrate to construct the heterojunction solar cells via simple spin-coating process have been presented. The total reflectance of chemically-derived graphene on pyramidal Si is similar to 12% at the wavelength of 550 nm which is remarkably reduced compared with that of reduced graphene oxide on planar Si. By modifying the density and distribution of reduced graphene oxide flakes on Si, the power conversion efficiency of 5.20% is achieved. Additionally, the simulated absorbance of different-thick graphene is implemented to optimize the performance of graphene/pyramidal Si devices. The fabrication technique for rGO-based devices has the merits of simplicity, large scale, high throughput and low cost, which is a new starting point in the direction of graphene-based material for the applications of next generation optoelectronics.