Cobalt oxide silica membranes for desalination

► CoOxSi membranes processed low (NaCl 1 wt.%) and high salinity (7.5-15 wt.%) waters. ► CoOxSi films became hydrostable after 5 days of water exposure up to 75 °C. ► Best water fluxes of 1.8 kg m−2 h−1 at 1 wt.% salt feed concentration. ► High salt rejections >99% were mainly attributed to CoOxSi molecular sieving.