Our recent publication in Journal of Materials Chemistry A 2023, 11, 19854 (doi 10.1039/d3ta03654e) in collaboration with the Institute of Chemical Technology (UPV-CSIC) in Valencia (among others) adresses the problem found in Tandem Catalysis of having»spatially proximate but thermally distant» catalysts contained in a single reactor. An elegant solution arose through the specific heating of the hot catalyst by magnetic susception. A thermal gradient of 50 ºC between the hot and cold catalysts was infered by luminescence lifetime thermometry by using Eu3+-doped and Cr3+-doped nanoprobes. A probe of concept was demostrated by direct production of propene from ethene, via sequential olefin dimerization and metathesis reactions.