Lin Yuan, Wang Ying, Feng Ziying, Gui Yunyun, Liu Lijun
Hubei Key Laboratory of Biomass Fibers and Eco-dyeing & Finishing, School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430200, PR China.
Hubei Key Laboratory of Biomass Fibers and Eco-dyeing & Finishing, School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430200, PR China.
J Colloid Interface Sci. 2025 Mar 15;682:381-391. doi: 10.1016/j.jcis.2024.11.232. Epub 2024 Nov 30.
Photocatalytic HO synthesis offers an efficient and sustainable means to convert solar energy into chemical energy, representing a forefront and focal point in photocatalysis. S-scheme heterojunctions demonstrate the capability to effectively separate photogenerated electrons and holes while possessing strong oxidation and reduction abilities, rendering them potential catalysts for photocatalytic HO synthesis. However, designing S-scheme heterojunction photocatalysts with band alignment and close contact remains challenging. Here we report CeOS/CeO multiphase nanofibrous prepared via an in situ sulphuration/de-sulphuration strategy. This in situ process enables intimate contact between the two phases, thereby shortening the charge transfer distance and promoting charge separation. The interfacial electronic interaction and charge separation were investigated using in situ X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations. The work function difference enables CeOS to donate electrons to CeO upon combination, resulting in the formation of an internal electric field (IEF) at interfaces. This IEF, along with bent energy bands, facilitates the separation and transfer of photogenerated charge carriers via an S-scheme pathway across the CeOS/CeO interfaces. The CeOS as the reduction photocatalyst exhibits significant O adsorption and activation along with a low energy barrier for the HO production. The optimal CeOS/CeO nanofibers heterojunction demonstrate enhanced photocatalytic HO production of 2.91 mmol gh, 58 times higher than that of pristine CeO nanofibers. This investigation provides valuable insights for the rational design and preparation of intimate contact nanofibrous heterojunctions with efficient solar HO synthesis.
光催化合成过氧化氢提供了一种将太阳能转化为化学能的高效且可持续的方法，是光催化领域的前沿和焦点。S型异质结能够有效分离光生电子和空穴，同时具有很强的氧化和还原能力，使其成为光催化合成过氧化氢的潜在催化剂。然而，设计具有能带匹配和紧密接触的S型异质结光催化剂仍然具有挑战性。在此，我们报道了通过原位硫化/去硫化策略制备的CeOS/CeO多相纳米纤维。这种原位过程使两相之间紧密接触，从而缩短了电荷转移距离并促进了电荷分离。利用原位X射线光电子能谱（XPS）和密度泛函理论（DFT）计算研究了界面电子相互作用和电荷分离。功函数差使CeOS在复合时能够向CeO提供电子，从而在界面处形成内电场（IEF）。这种IEF与弯曲的能带一起，通过S型途径促进了光生载流子在CeOS/CeO界面上的分离和转移。作为还原光催化剂的CeOS表现出显著的氧吸附和活化，以及较低的过氧化氢生成能垒。最优的CeOS/CeO纳米纤维异质结表现出增强的光催化过氧化氢生成能力，为2.91 mmol g⁻¹ h⁻¹，比原始CeO纳米纤维高58倍。这项研究为合理设计和制备具有高效太阳能驱动过氧化氢合成的紧密接触纳米纤维异质结提供了有价值的见解。
