Solid waste and graphite derived solar steam generator for highly-efficient and cost-effective water purification

•Efficient solar evaporator was developed from solid wastes and graphite.•Solar evaporation rate as high as 1.61 kg/m2 h was achieved under 1 sun.•Quantitative studies suggest the design of highly-efficient solar steam generator.•High efficiency and cycling stability were proved for purifying various water.•Prototype can produce 8–13 L of clean water daily with 1 m2 of material.