A metal foam, such as copper metal foam, is used for water filtration and purification. A method is used to manufacture a new water purification device with the capability of killing bacteria and viruses using three dimensionally connected copper foam filter consisting of random or elongated channel pores and large surface area, thereby increasing the copper surface area in contact with contaminated water drops and purifying them. The copper foam water filter has pores on the order of several to tens of micrometers and porosity ranging from 50 percent to 75 percent to properly control the water filtration time and the contact time between the copper foam pore surface and water drops during filtration.