Metal–organic frameworks (MOFs) based on Ti-oxo clusters (Ti-MOFs) represent a naturally self-assembled superlattice of TiO₂ nanoparticles separated by designable organic linkers as antenna chromophores, epitomizing a promising platform for solar energy conversion. However, despite the vast, diverse, and well-developed Ti-cluster chemistry, only a scarce number of Ti-MOFs have been documented. The synthetic conditions of most Ti-based clusters are incompatible with those required for MOF crystallization, which has severely limited the development of Ti-MOFs. This challenge has been met herein by the discovery of the [Ti₈Zr₂O₁₂(COO)₁₆] cluster as a nearly ideal building unit for photoactive MOFs. A family of isoreticular photoactive MOFs were assembled, and their orbital alignments were fine-tuned by rational functionalization of organic linkers under computational guidance. These MOFs demonstrate high porosity, excellent chemical stability, tunable photoresponse, and good activity toward photocatalytic hydrogen evolution reactions. The discovery of the [Ti₈Zr₂O₁₂(COO)₁₆] cluster and the facile construction of photoactive MOFs from this cluster shall pave the way for the development of future Ti-MOF-based photocatalysts.

中文翻译：

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[Ti ₈ Zr ₂ O ₁₂（COO）₁₆ ]簇：用于光敏金属-有机骨架的理想无机建筑单元

基于Ti-oxo团簇（Ti-MOFs）的金属有机框架（MOF）代表了TiO ₂纳米粒子的自然自组装超晶格，这些纳米晶格被可设计的有机连接物分隔为天线发色团，是太阳能转化的有前途的平台。然而，尽管Ti团簇化学具有广泛，多样和完善的发展，但仅有少量的Ti-MOF被记录在案。大多数Ti基团簇的合成条件与MOF结晶所需的条件不相容，这严重限制了Ti-MOF的发展。通过发现[Ti ₈ Zr ₂ O ₁₂（COO）₁₆]簇是光敏MOF的近乎理想的构建单元。组装了一系列等孔的光敏MOF，并在计算指导下通过有机连接基的合理官能化对它们的轨道排列进行了微调。这些MOF表现出高孔隙率，出色的化学稳定性，可调节的光响应以及对光催化氢释放反应的良好活性。[Ti ₈ Zr ₂ O ₁₂（COO）₁₆ ]团簇的发现以及从该团簇中轻松构建光活性MOF应当为未来基于Ti-MOF的光催化剂的开发铺平道路。