A one-pot strategy for anchoring single Pt atoms in MOFs with diverse coordination environments

It is challenging to precisely control and identify the coordination environment of single-atom active sites due to non-uniform substrate surfaces. This complicates the task of bridging experimental and theoretical investigations. Here, using a one-pot method, we immobilized single Pt(0) atoms within various terephthalic acid-based metal–organic frameworks, thereby constructing well-defined active sites with varied organic coordination environments. In the isoreticular metal–organic framework UiO-6–X (–X = –H, –NH₂, –Br and –I), influenced by the functional groups, the resulting Pt₁ sites exhibited distinct catalytic activities for hydrogenation and sintering resistance. Mechanistic studies reveal that this is related to alteration of the electronic state of Pt centres and the adsorption behaviour of intermediates on the Pt sites. Pt₁@UiO-66–Br gave the highest activity and excellent thermal stability, with no metal agglomeration in H₂ up to 300 °C. Our work introduces a strategy for the precise environmental modification of isolated metal atoms for better catalytic performance.