Figure 5. Solar-powered water purification equipment based on MF@HPB-PPy10-OA in realistic outdoor environment. (a) Lateral view, (b) top view (photo credit: Chun Chang, NENU) and (c) internal construction view. (d) Real-time monitoring of SVG data from 5:00 to 17:00. Purity measurements by using a multimeter: (e) world sea, (f) purified water, (g) drinking water (from the water purifier supply system of NENU) and (h) ultrapure water. (i) Salinity of two simulated seawater samples (3.5 wt% and 10.0 wt%) before and after purification based on MF@HPB-PPy10-OA.
intensity of about 0.61kw m-2), which is sufficient to meet the average daily drinking water demand of an adult. Impedance measurements are conducted by multimeter to evaluate the electrolyte concentration and purity of the purified water. In Figure 5e-5h, the water purification effect is outstanding and the water quality is markedly superior to the drinking water supplied by daily water purifier and well above that of seawater. After desalination, the salinities of water in samples (3.5 wt% and 10 wt% salinity) are all below the WHO and EPA (World Health Organization and US Environmental Protection Agency) drinking water quality standards by 1 to 2 orders of magnitude. The major ions, such as Na+, Mg2+, K+ and Ca2+, are decreased in concentration by 3-4 orders of magnitude compared to seawater (Figure S20). This system can also be applied to the purification of industrial wastewater containing heavy metals or dyes (Figure S21a and Figure S21b), where the concentration of pollutants in the purified water is also reduced greatly and meets the discharge standards. These outstanding purification results demonstrate the great potential of MF@HPB-PPy10-OA for practical photothermal seawater desalination and wastewater purification. Furthermore, the advantages of MF@HPB-PPy10-OA in terms of mechanical properties, applicability and fabrication process (simple, low-cost and batch fabrication) allow for facile scale-up in commercialization (2.7 USD m-2, see section 2.2 synthesis for details).