Unraveling the coordination structure-performance relationship in Pt1/Fe2O3 single-atom catalyst

Abstract

Heterogeneous single-atom catalyst (SAC) opens a unique entry to establishing structure–performance relationship at the molecular level similar to that in homogeneous catalysis. The challenge lies in manipulating the coordination chemistry of single atoms without changing single-atom dispersion. Here, we develop an efficient synthetic method for SACs by using ethanediamine to chelate Pt cations and then removing the ethanediamine by a rapid thermal treatment (RTT) in inert atmosphere. The coordination chemistry of Pt single atoms on a Fe2O3 support is finely tuned by merely adjusting the RTT temperature. With the decrease in Pt-O coordination number, the oxidation state of Pt decreases, and consequently the hydrogenation activity increases to a record level without loss of chemoselectivity. The tunability of the local coordination chemistry, oxidation states of the metal, and the catalytic performance of single atoms reveals the unique role of SACs as a bridge between heterogeneous and homogeneous catalysis.

Stable single platinum atoms trapped in sub-nanometer cavities in 12CaO·7Al2O3 for chemoselective hydrogenation of nitroarenes

“…4a, e). Here, the hydrogen activation process may also be promoted by the Pt single atoms with low CN of Pt-O in the surface cavities of C12A7, which is in good agreement with Pt 1 /Fe 2 O 3 55 . The 0.1Pt/ C12A7-800 and 0.1Pt/C12A7-1000 catalysts without single atomic species and with lower surface alkalinity exhibit much poorer catalytic performance, as shown in Fig.…”

Entropy-stabilized single-atom Pd catalysts via high-entropy fluorite oxide supports

“…An appropriate amount of H 2 PdCl 6 (K 2 PdCl 6 dissolved in diluted hydrochloric acid, corresponding to a Pd loading of 0.5 wt%) solution was added dropwise into the HEFO solution under magnetically stirring 51 . After continuing stirring for 5 h and followed by aging for 5 h, the suspension was filtered and washed with deionized water for several times, and dried at 60°C under vacuum 52 and then calcined at 300 and 900°C in air for 2 h, respectively, denoted as Pd/HEFO-p and Pd/HEFO-p-900.…”

Heterogeneous Single‐Atom Catalysts for Electrochemical CO2 Reduction Reaction

“…Apart from N and C coordinated atoms, the single metal atoms can also bond with O [ 92–94 ] and S [ 95 ] or form metal–metal bonds, [ 96 ] resulting in different electronic and geometric properties of the central atoms. In summary, the coordination environment of the single atoms in SACs, including the coordinated atoms, coordination numbers and the second‐ and high‐coordination shell, has a significant effect on the microscopic properties and catalytic performances of SACs.…”