Advances in single-atom catalysis

Conventional homogeneous strategies for the synthesis of deuterated alcohols — valuable synthetic targets due to their roles in pharmaceuticals, materials, and mechanistic studies — present limitations in terms of cost and catalyst recovery, with heterogeneous catalysis providing recyclability and enhanced scalability. In this Perspective, the authors discuss the evolution of heterogeneous catalytic systems into scalable and efficient platforms for deuterated alcohol synthesis, highlighting new directions for sustainable isotope incorporation.

Using Pd homogeneous catalysts for direct C–H arylation is an attractive approach for synthesizing natural products and organic functional materials, but limitations in terms of cost and catalyst recovery could be alleviated by alternative heterogeneous catalytic processes. Here, the authors report a Pd single-atom/cluster cocatalyst supported on non-enzymatic browning glucose for the direct coupling of inert C-H bonds with aryl iodides that breaks the activity-stability trade-off via a Pd^II/Pd^IV catalytic cycle, and demonstrate C(sp³)-H or C(sp²)-H bond activation tunability by tailoring the structure of the catalyst support.

Single atom catalysts dispersed on a surface demonstrate great promise for a variety of catalytic reactions, but their aggregation leads to a degradation of catalytic activity. Here, the authors use quantum mechanical calculations to study the catalytic activity of Cu adatoms stabilized with N-heterocyclic carbenes (NHCs) on a Cu(100) surface, finding that NHC-decoration significantly reduces the energy barriers to electrocatalytic CO hydrogenation and C–C coupling.

Economical and high-efficiency synthesis of single-atom catalysts is a tremendous challenge hampering their large-scale industrialization, which is mainly attributed to the complex equipment and processes necessary for both top-down and bottom-up synthesis methods. Now, a facile three-dimensional printing approach tackles this dilemma. From a solution of printing ink and metal precursors, target materials with specific geometric shapes are prepared with high output, directly and automatically.

Single-atom catalysts (SACs) are highly promising materials for applications such as electrocatalytic water splitting, but coordination geometries around catalyst centers remain the subject of debate. Here, the authors use spin-polarized ab initio molecular dynamics simulations to compare the aqueous reactivities of iron porphyrin and iron pyridine SACs embedded in graphene, and predict the interfacial water dissociative adsorption mechanism under a moderate electric field for an iron porphyrin SAC.

Fe-N-C single atom electrocatalysts offer high catalytic activities for the oxygen reduction reaction, but limited attention has been paid to the morphology of the catalyst layers. Here, the authors demonstrate the impact of three different commercial ionomers on the electrocatalytic performance of porous Fe-N-C layers in alkaline media.

Dry reforming of methane (DRM) is a promising method for sustainable valorisation of methane and carbon dioxide, but its application is hampered by sintering of the active catalytic phase and coke formation. Here, the authors study DRM with non-noble metal atoms in supported gallium-rich liquid alloys which suppress both catalyst sintering and coke formation.