Photoelectric conversion device and method for producing the same

A photoelectric conversion device comprising:

• a positive electrode;
• a negative electrode;
• a photoelectric conversion layer including poly-[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] as a p-type organic semiconductor material and including fullerene or a fullerene derivative as an n-type organic semiconductor material;
• and
• a buffer layer, provided between the positive electrode and the photoelectric conversion layer, including MoO3,
• wherein the p-type organic semiconductor material and the n-type organic semiconductor material are in a mixed state over the entirety of the photoelectric conversion layer, and the proportion of the p-type organic semiconductor material in a first region, which is directly in contact with a surface of the buffer layer and extending within the photoelectric conversion layer, is higher than the proportion of the p-type organic semiconductor material in the entirety of the photoelectric conversion layer, and the proportion of the p-type organic semiconductor material in a second region, which is directly in contact with a surface of the negative electrode and extending within the photoelectric conversion layer, is lower than the proportion of the p-type organic semiconductor material in the entirety of the photoelectric conversion layer.