A Simple Disinfection Device for Families in Underdeveloped Regions

Nearly one-third of the global population lacks access to safe drinking water, with the unavailability of simple and efficient disinfection devices being a key contributing factor. Mercury lamps are effective, safe, and reliable UV-based disinfection devices, whereas their application is limited to regions with a stable power supply. Here, we design a manually operated triboelectric-electromagnetic hybrid generator able to power a UV mercury lamp. Combining the advantages of a triboelectric nanogenerator and an electromagnetic generator, this unit exhibits electrical output of variable impedance characteristics, matching the power requirement of UV mercury lamps. Powered with cranking or pedaling, enabled by our tailor-designed transmission system, the device achieves 8-log pathogen removal from 2 L of water in 25 min with cranking or 10 L in 15 min with pedaling. The latter is sufficient to meet the daily drinking water needs of a family of four set by the World Health Organization. With a low capital cost, this grid-free UV disinfection system could potentially provide safe drinking water, at a levelized cost of 8.57 USD/(capita·yr) to ∼1.8 billion people in over 375 million households in underdeveloped countries/regions, substantially contributing to the United Nations Sustainable Development Goal 6.