NOVELTY - A photovoltaic device has inorganic nanostructured template, charge-transfer material (108) coating template leaving additional space, and charge-transfer material (109). Template has template elements having diameter of 1-500 nm and density of 1012-1016 elements/m2. Lowest unoccupied molecular orbital (LUMO) or conduction band of material (108) differs from LUMO or conduction band of material (109) by more than 0.2 eV.    USE - E.g. solar cell.    ADVANTAGE - The photovoltaic device has favorable corrosion resistance and leakage resistance, and effectively absorbs light. The photovoltaic device is economical, and efficiently converts incident light to electrical energy.    DETAILED DESCRIPTION - A photovoltaic device has an insulating inorganic nanostructured template, a charge-transfer material (108) coating the nanostructured template material leaving additional space, and a charge-transfer material (109) filling the additional space. The template has regular template elements having diameter of 1-500 nm and structure density of 1012-1016 elements/m2. The materials (108,109) are volumetrically inter-digitated, and have complementary charge transfer properties with respect to each other. The lowest unoccupied molecular orbital (LUMO) or conduction band of material (108) differs from LUMO or conduction band of material (109) by more than 0.2 eV. The absorbance of material (108 and/or 109) is more than 103/cm at the peak of absorption.    An INDEPENDENT CLAIM is included for formation of photovoltaic device, which involves forming the nano-structured template having template elements, coating one or more walls of template elements with charge transfer material (108), such that additional space is left, and filling the additional space with charge transfer material (109).    DESCRIPTION OF DRAWING(S) - The figure shows a vertical cross-sectional view of photovoltaic device.    active layer (101)    interface layer (104)    transparent conducting electrode (106)    optical conductive layer (107)    charge transfer materials (108,109)    base electrode (110)    metal layer (112)