This　research　investigated　photo-Fenton　enhanced　in　a　twin-reactor　for　hydrogen　evolution　and　wastewater　photodegradation　simultaneously.　The　twin-reactor,　which　was　two　coupled　reactors　divided　by　a　membrane,　can　simultaneously　photodegrade　isopropanol　wastewater　and　separate　hydrogen　from　water　splitting.　Fe2+/Fe3+　pair　was　used　as　electron　mediator　in　the　twin　reactor　by　counter-diffusing　between　hydrogen　and　photodegradation　sides.　Moreover,　Fe3+　also　triggered　photo-Fenton　reaction　to　enhance　the　degradation　of　organic　wastewater.　SrTiO3:Rh,　Pt/SrTiO3:Rh　and　Ru/SrTiO3:Rh　were　used　for　hydrogen　evolution.　For　isopropanol　degradation,　P25　(TiO2)　and　WO3　were　applied.　The　light　source　was　simulated　sunlight　using　300　W　Xe　lamps　with　AM1.5　filter.　Compared　with　the　single　reactor,　the　isopropanol　removal　increased　125%　and　hydrogen　evolution　was　up　37%　due　to　H2　separation　and　inhibition　of　reverse　reaction　of　water　splitting.　In　the　twin　reactor,　95%　of　pure　hydrogen　was　obtained　in　the　hydrogen　evolution　side,　thus　saved　the　cost　of　afterward　purification.　©　2020　Elsevier　B.V.