Preparation and deposition of supercooled, electron-doped, water-cluster clathrate nanoparticles in confined geometries and on substrates from proprietary nanoemulsions is described. The compositions can yield high-Tc superconductors, e.g., in the vicinity of −43 deg C., useful for SQUID devices in electronic and magnetic application. In certain embodiments, the water-cluster clathrates are formed in nanoemulsions.