Cerium Metal–Organic Framework Incorporating Quinoline Sulfonic Acid for Photocatalytic Carbon Dioxide Reduction

Cerium metal–organic frameworks (Ce-MOFs) have
attracted
extensive attention due to their potential in photocatalytic applications.
However, Ce-MOFs constructed with organic carboxylic acids as ligands
typically exhibit wide band gaps, which limit their utilization in
the visible-light region. This work proposes a strategy to design
visible-light-active Ce-MOFs by employing quinoline sulfonic acid
as a ligand. The synthesized compound (1-Ce) features
a high surface area, open Ce metal sites, and large-sized 1D channels.
Benefiting from ligand-to-metal charge transfer, 1-Ce demonstrates good visible light absorption. Additionally, the chelating
coordination of nitrogen and oxygen atoms endows 1-Ce with excellent chemical stability. Owing to its abundant metal sites,
high porosity, and visible light responsiveness, 1-Ce exhibits outstanding photocatalytic activity for CO2 reduction
under visible light, achieving a CO production rate of 138 μmol·g–1·h–1surpassing previously
reported Ce-MOF photocatalysts.

铈基金属有机框架（Cerium metal–organic frameworks, Ce-MOFs）因其在光催化应用领域的潜在价值而受到广泛关注。然而，以有机羧酸为配体构建的Ce-MOFs通常具有较宽的带隙，这限制了其在可见光区域的实际应用。本研究提出了一种以喹啉磺酸为配体，设计具备可见光响应活性的Ce-MOFs的策略。合成得到的化合物（1-Ce）具备高比表面积、开放的铈金属位点以及大尺寸一维通道。得益于配体到金属的电荷转移效应，1-Ce展现出优异的可见光吸收性能。此外，氮、氧原子的螯合配位作用赋予1-Ce出色的化学稳定性。凭借丰富的金属位点、高孔隙率以及可见光响应特性，1-Ce在可见光驱动的CO₂还原反应中表现出优异的光催化活性，一氧化碳生成速率可达138 μmol·g⁻¹·h⁻¹，优于此前已报道的Ce-MOF类光催化剂。