A recyclable ZnIn2S4/PAN photocatalytic nanofiber membrane for boosting visible light hydrogen evolution in seawater without cocatalyst

Using seawater for photocatalytic hydrogen production is always a highly promising direction. However, traditional powdered photocatalysts encounter challenges like ion interference and difficulty in reuse. To address these issues, we have combined the photocatalyst ZnIn2S4 (ZIS) with a polymer (PAN) using electrospinning technology to produce a composite photocatalytic ZIS/PAN nanofiber membrane. In aqueous solution, the ZIS/ PAN nanofiber membrane achieves a maximum hydrogen evolution rate of approximately 1836 mu mol/g/h, which is 3.37 times that of ZIS particles. Additionally, cyanide groups on PAN fibers can capture a small portion of photogenerated electrons, which then adsorb ions from seawater, reducing their impact on the photocatalyst and demonstrating excellent seawater hydrogen production performance. At specific ion concentrations, the membrane's activity is 20 % higher than in aqueous solution. Moreover, it overcomes the limitations of powdered photocatalyst structures, enabling device integration that facilitates easy recovery and reuse.