NOVELTY - A photovoltaic device comprises a nano-structured template made from n-type first charge transfer-material; a p-type second charge-transfer material conformally coating at least one wall of the template elements leaving additional space; and a third material in the additional space. The third material is a p-type or conducting material that volumetrically interdigitates with the second charge-transfer material.    USE - As photovoltaic device, e.g. solar cells or other devices.    ADVANTAGE - The device is solid-state device that do not contain a liquid electrolyte and thus are subject to significantly fewer leakage and corrosion problems of the type associated with devices using liquid electrolytes. The charge-splitting layer of the device exhibits a three-dimensional topology that is very regular along its length and width, but also along its depth. The device is not dye-sensitized and do not depend entirely on a monolayer of a dye adsorbed to an n-type inorganic material as a light absorber and absorb light more effectively and can be more efficient on a volume basis in converting incident light to electrical energy. The device does not use a liquid-based electrolyte or redox chemistry to transport holes away from the light absorbing material. The devices can be produced on large-scale with low-cost.    DETAILED DESCRIPTION - A photovoltaic device comprises a nano-structured template made from n-type first charge transfer-material; a p-type second charge-transfer material conformally coating at least one wall of the template elements leaving additional space; and a third material in the additional space. The third material is a p-type or conducting material that volumetrically interdigitates with the second charge-transfer material. A lowest unoccupied molecular orbital (LUMO) or conduction band of the first charge-transfer material differs from a LUMTO or conduction band of the second charge-transfer material by less than 1 eV. A light absorbance of at least one charge transfer material is greater than 103/cm at the peak of the absorption spectrum. The nano-structured template has template elements of 1 - 500 nm in diameter with a template element density of 1012 - 1016 elements/m2.    An INDEPENDENT CLAIM is included for making a photovoltaic device involving    (a) forming a nanostructured template from a first charge-transfer material;    (b) coating the walls of the template elements with a second charge-transfer material in a way that leaves additional space; and    (c) filling the additional space with a third charge-transfer material that includes elongated structures that interdigitated the second charge transfer material.    The second charge-transfer material has complementary charge-transfer properties with respect to the first charge-transfer material.