Plasmonic nanostructures are synthesized by decorating B- or N-doped carbon nanotubes (CNTs) with Au nano-particles. While the plasmonic nano-particles promote exciton generation and dissociation, the B- and N-doped CNTs enable charge-selective transport enhancement in the organic active layer. Such concurrent enhancements of all the principal energy-harvesting steps improve the device efficiency up to 9.98% for organic single-junction solar cells.