A method includes coating, via chemical vapor deposition, electronics disposed on a printed circuit board (PCB) with an electrical insulation coating of between one micron to 25 microns. The method further include depositing, on the electrical insulation coating, a metallic nano-layer comprising a porous metallic nano-structure. The method further includes, after the coating and the depositing, immersing the PCB in a water-based fluid to cool the electronics while the electronics are powered on.