Water is the foundation of life. Although 75% of the Earth’s surface is covered by water, 97% of the water is salty water, leaving only 3% as fresh water. However, two-thirds of the fresh water on Earth is frozen in snow and ice in glaciers and ice caps, which leaves only about 1% of all the Earth’s water as liquid and fresh, making it a very scarce natural resource. Nowadays, water scarcity is a severely growing problem in semi-arid desert regions, land-scarce countries, and in countries with high levels of economic activity. As more people put ever increasing demands on limited supplies, the cost and effort to build or even maintain access to water is increasing. So far to meet the increasing freshwater requirements, many countries depend on desalination technologies to obtain fresh water should economic conditions allow.^1–5  Particularly in the Middle East, seawater desalination is a vital freshwater resource in countries such as Saudi Arabia, United Arab Emirates, and Kuwait.⁵  However, due to the high energy consumption in these desalination processes, rising energy costs, and diminishing fossil fuel stock, more sustainable desalination methods that utilize alternative energy resources are still highly desired.^6–10  On the other hand, in remote and rural areas where access to centralized drinking water supply and even electricity is unavailable, the desalination method is not suited.^11–15