A radioisotope power sources that includes radioisotope nanoparticles and scintillator materials. An embodiment of the radioisotope power source includes radioisotope nanoparticles suspended within a polycrystalline scintillator; additional polycrystalline scintillator at least partially surrounding the polycrystalline scintillator with the radioisotope nanoparticles; and a photovoltaic device in light communication with the surrounding polycrystalline scintillator. A system that employs the radioisotope power source and a method of generating an electrical current are also disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.