Abstract: The present disclosure relates to a rotary triboelectric generator, device comprising different triboelectric materials for generating electricity, said generator comprising: a rotor shaft; a first triboelectric material plate fixed on said shaft; a bracket framework for receiving at least a second triboelectric material plate; a second triboelectric material plate fixed in said framework; arranged such that the first triboelectric plate comes into successive contacting and sliding against the second triboelectric plate, when said rotor shaft rotates, wherein both the first triboelectric material plate and the second triboelectric material plate are flexible plates. In particular, the first triboelectric material plate and the second triboelectric material plate are flexible plates having a different stiffness. In particular, the plate or plates fixed on the shaft are flexible and the plate or plates fixed on the brackets are stiff or flexible but less flexible than the plate or plates fixed on the shaft.