A General Strategy to Immobilize Single‐Atom Catalysts in Metal–Organic Frameworks for Enhanced Photocatalysis. Issue 6 (23rd December 2021)

• Record Type: Journal Article
• Authors: Sui, Jianfei; Liu, Hang; Hu, Shaojin; Sun, Kang; Wan, Gang; Zhou, Hua; Zheng, Xiao; Jiang, Hai‐Long
• Is Part Of: Advanced materials. Volume 34:Issue 6(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-23
• Subjects: H 2 production -- metal–organic frameworks -- photocatalysis -- single‐atom catalysts; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202109203
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Single‐atom catalysts (SACs) are witnessing rapid development due to their high activity and selectivity toward diverse reactions. However, it remains a grand challenge in the general synthesis of SACs, particularly featuring an identical chemical microenvironment and on the same support. Herein, a universal synthetic protocol is developed to immobilize SACs in metal–organic frameworks (MOFs). Significantly, by means of SnO2 as a mediator or adaptor, not only different single‐atom metal sites, such as Pt, Cu, and Ni, etc., can be installed, but also the MOF supports can be changed (for example, UiO‐66‐NH2, PCN‐222, and DUT‐67) to afford M1 /SnO2 /MOF architecture. Taking UiO‐66‐NH2 as a representative, the Pt1 /SnO2 /MOF exhibits approximately five times higher activity toward photocatalytic H2 production than the corresponding Pt nanoparticles (≈2.5 nm) stabilized by SnO2 /UiO‐66‐NH2 . Remarkably, despite featuring identical parameters in the chemical microenvironment and support in M1 /SnO2 /UiO‐66‐NH2, the Pt1 catalyst possesses a hydrogen evolution rate of 2167 µmol g –1 h –1, superior to the Cu1 and Ni1 counterparts, which is attributed to the differentiated hydrogen binding free energies, as supported by density‐functional theory (DFT) calculations. This is thought to be the first report on a universal approach toward the stabilization of SACs with identical chemical microenvironment on an identical support. Abstract : Single‐atom catalysts (SACs) are immobilized in metal–organic frameworks (MOFs) by a general strategy with SnO2 as a mediator onto metal–oxo clusters via a two‐step microwave‐assisted modification approach. Remarkably, the H2 production efficiency of Pt1 /SnO2 /UiO‐66‐NH2 under visible light surpasses that of Cu1 /SnO2 /UiO‐66‐NH2 and Ni1 /SnO2 /UiO‐66‐NH2, surpassing that of their corresponding metal nanoparticles (NPs) by far.