Dipotassium-2,3,9,10,16,17,23,24-octacyanophthalocyanine-potassium (K2Pc(CN)(8)-K) complex nanograss was fabricated on a single KCl crystal. The process was controlled to achieve monodisperse nanograss with individual rod diameters of 60 nm and lengths of 250 nm. The gaps between the rods were fully covered with K2Pc(CN)(8)-K complex grains. The film continuity at the interface between the substrate and the nanograss layer allowed measurement of the field-effect-transistor characteristics of the material. The K2Pc(CN)(8)-K complex film exhibited n-type conduction characteristics, and the energy of the highest occupied molecular orbital was determined to be 5.8 eV. Organic photovoltaic cells containing K2Pc(CN)(8)-K as an n-type semiconductor were also fabricated, and the power-conversion efficiency of a cell containing vertical-aligned-nanograss was approximately four times larger than that of a nanograss dispersed bulk-heterojunction-type cell. (C) 2013 Elsevier B.V. All rights reserved.