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• The g-C3N4/TiO2 heterojunction nanoparticles are firmly immobilised on PAA/PTFE UFM. • The g-C3N4/TiO2/PAA/PTFE UFM shows superb hydrophilicity, anti-fouling and water flux. • Exceptional visible-light regeneration of the fouled g-C3N4/TiO2/PAA/PTFE is demonstrated. • The enhanced anti-fouling and photocatalytic self-cleaning mechanisms are reasonalised. Membrane fouling due to superhydropobicity of polytetrafluoroethylene ultrafiltration membranes (PTFE UFMs) represents a grand challenge for their practical applications in diverse water treatment industries. Surface immobilisation of hydrophilic and chemically stable inorganic metal oxides (TiO 2 , ZrO 2 , etc) has been developed to improve hydrophilicity of the PTFE UFMs, though they still suffer from expensive and repeating regenerations once fouled. To address such issues, we strive to firmly immobilize g-C 3 N 4 modified TiO 2 (g-C 3 N 4 /TiO 2 , hereafter CNTO) onto PTFE UFM via a facile plasma-enhanced surface graft technique using polyacrylic acid (PAA) as a bridging agent. As reported here, the obtained CNTO/PAA/PTFE UFM shows much smaller surface water contact angle (WCA) of 62.3° than that of bare PTFE UFM(115.8°), leading to enhanced water flux of 830 L m−2 h-1 in the initial ultrafiltration of modelled waste-water containing methylene blue (MB). The CNTO/PAA/PTFE UFM is highly resistant to fouling in the prolonged filtration of 1000 mg/L bovine serum albumin (BSA) solution, while the fouled CNTO/PAA/PTFE UFM is able to regenerate rapidly under either UV or visible-light irradiation. The enhanced performance of the novel CNTO/PAA/PTFE UFM is reasonably attributed to its high wettability and robust photocatalytic activity of the g-C 3 N 4 /TiO 2 coating that follows different self-cleaning mechanisms under UV and visible light irradiations. [ABSTRACT FROM AUTHOR]