Metal/metal oxide nanoparticle-embedded polymer films were synthesized in situ wherein the polymerizing agent was utilized for both reduction and polymerization (such as curing). This in situ method avoids the use of any external reducing agent/stabilizing agent and leads to a uniform distribution of nanoparticles in the polymer matrix. In some embodiments, additional heating can be utilized to form the nanoparticles embedded in the polymer film.