Unveiling the Ir single atoms as selective active species for the partial hydrogenation of butadiene by operando XAS

Abstract

Single-atom catalysts represent an intense topic of research due to their interesting catalytic properties for a wide range of reactions. Clarifying the nature of the active sites of single-atom catalysts...

Regulating the electronic structure of single-atom catalysts for electrochemical energy conversion

“…[25][26][27][28][29] Since SACs were rst reported in 2011, numerous precious metal SACs, such as Pt, Ir, Ru, and Au, have been obtained through different synthetic strategies, i.e., co-precipitation, impregnation, atomic layer deposition, high-temperature pyrolysis, and low-temperature chemical reduction. [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49] To further lower the cost of precious metal SACs, 3d transition metal SACs, such as Fe, Co, and Ni, were also fabricated via bonding with O, N, S, and P atoms or anchoring at the defects to increase the durability. [50][51][52] Metal SAs anchored to the substrates interact with each other to generate many active sites.…”

“…, co-precipitation, impregnation, atomic layer deposition, high-temperature pyrolysis, and low-temperature chemical reduction. 30–49 To further lower the cost of precious metal SACs, 3d transition metal SACs, such as Fe, Co, and Ni, were also fabricated via bonding with O, N, S, and P atoms or anchoring at the defects to increase the durability. 50–52 Metal SAs anchored to the substrates interact with each other to generate many active sites.…”

Tailoring the Selectivity of 1,3-Butadiene versus 1-Butene Adsorption on Pt(111) by Ultrathin Ionic Liquid Films

“…Different heterogeneous transition-metal catalysts have been applied successfully in this reaction, most prominently Pd-based ones, − but also Pt, − Ni, Co, Rh, Ir, , Fe, Ru, Cu, and even Au , catalysts have shown activity. − The selectivity can be improved by various strategies, such as using tuned supports, ,,, co-fed CO, different metal alloys, − ,,,, sulfide materials, , single-atom catalysts, ,,, and since recently also the SCILL concept. ,, In a solid catalyst with ionic liquid layer (SCILL), supported nanoparticles are modified by adding a layer of ionic liquids (ILs). , ILs consist solely of cations and anions and possess a remarkably low melting point, often below room temperature . Catalytic test experiments with a SCILL system showed very promising results, increasing the selectivity toward butenes from 0 to 99% at 99.5% 1,3-butadiene conversion compared to a commercial Pd catalyst …”

“…An additional challenge is catalyst deterioration by the accumulation of higher hydrocarbons, so-called green oil, which are the products of C−C coupling side reactions. 3,4 Different heterogeneous transition-metal catalysts have been applied successfully in this reaction, most prominently Pd-based ones, 5−11 but also Pt, 12−15 Ni, 16 Co, 17 Rh, 18 Ir, 19,20 Fe, 21 Ru, 21 Cu, 22 and even Au 23,24 catalysts have shown activity. 2−4 The selectivity can be improved by various strategies, such as using tuned supports, 6,13,18,24 co-fed CO, 18 different metal alloys, [6][7][8]14,15,21,25 sulfide materials, 8,26 single-atom catalysts, 9,13,14,20 and since recently also the SCILL concept.…”

“…3,4 Different heterogeneous transition-metal catalysts have been applied successfully in this reaction, most prominently Pd-based ones, 5−11 but also Pt, 12−15 Ni, 16 Co, 17 Rh, 18 Ir, 19,20 Fe, 21 Ru, 21 Cu, 22 and even Au 23,24 catalysts have shown activity. 2−4 The selectivity can be improved by various strategies, such as using tuned supports, 6,13,18,24 co-fed CO, 18 different metal alloys, [6][7][8]14,15,21,25 sulfide materials, 8,26 single-atom catalysts, 9,13,14,20 and since recently also the SCILL concept. 10,11,16 In a solid catalyst with ionic liquid layer (SCILL), supported nanoparticles are modified by adding a layer of ionic liquids (ILs).…”