A multi-layer structure β-FeOOH@GO/AgNWs membrane with robust photo-Fenton self-cleaning property for high-efficiency wastewater remediation

Developing an anti-fouling and multifunctional membrane with efficient separation performance is great potential for alleviating water crisis. Here, combining the heterogeneous β-FeOOH/Ag catalyst layer, intercepted GO nanosheets layer, and porous polyvinylidene fluoride (PVDF) substrate, a multi-layer composite membrane (β-FeOOH@GO/AgNWs) was designed and fabricated by the polyphenol (TA)-metal (Fe 3 + ) crosslinking and inductive effect. Hence, the β-FeOOH@GO/AgNWs membrane possesses robust physical and chemical stability, superhydrophilicity (water contact angle ∼0°) and underwater superoleophobicity (underwater oil contact angle >150°). Due to the construction of heterojunctions of β-FeOOH/Ag, the β-FeOOH@GO/AgNWs membrane achieved the degradation of various dyes under the photo-Fenton system, the degradation rate constant is 0.0986 min −1 . Meanwhile, the synergistic effect of multi-layer structure can efficiently intercept the various soluble dyes by electrostatic effect, π-π action and layered channels, the reject rate recached above 97.89 % under the acidic and neutral environment. Faced the membrane fouling phenomenon during the separation process, the flux and rejection of fouled membrane recovered to above 95.1 % and 97.9 % after photo-Fenton cleaning for 10 min. Moreover, the β-FeOOH@GO/AgNWs membrane also realized efficient separation performance for various oil-in-water emulsions, the flux reached 329.2 ± 25–486.1 ± 15 L m −2 h −1 bar −1 , the corresponding separation efficient was above 99 %. Similarly, the photo-Fenton cleaning strategy also regenerated the fouled composite membrane, the flux recovery rate was above 95 %. Therefore, we think that β-FeOOH@GO/AgNWs membrane can bring a new thinking of developing the multifunctional membrane to achieve complex wastewater remediation.