Continuous electrochemical water splitting from natural water sources via forward osmosis

Significance The growing need for the widespread adoption of renewable energy necessitates scalable energy storage. A potential route to meeting this challenge is electrochemical water splitting driven by renewable energy that will require, at scale, abundant and accessible sources of water. Recognizing that 96.5% of global water reserves exist as brackish water and seawater, water splitting approaches utilizing these sources and other impure water sources are warranted. The approach described here couples water splitting with forward osmosis to enable saltwater to be utilized directly without pretreatment or purification while circumventing the challenges posed by impurities and parasitic energy-wasting side reactions.