Example embodiments relate to optoelectronic devices. An optoelectronic device may include a photoactive layer between first and second electrodes, and a ferroelectric layer corresponding to at least one of the first and second electrodes. At least one of the first and second electrodes may include graphene. The photoactive layer may include a two-dimensional (2D) semiconductor. The optoelectronic device may further include a third electrode, and in this case, the ferroelectric layer may be between the second electrode and the third electrode. The second electrode, the ferroelectric layer, and the third electrode may constitute a nanogenerator.