Efficient methanol upcycling to ethylene glycol and glycolaldehyde via divergent C−C coupling synthesis

Direct photocatalytic conversion of methanol into high-value multi-carbon chemicals through precisely controlled C − C coupling represents an extremely appealing but challenging goal. Herein, we demonstrate the efficient photoredox-driven dehydrocoupling of methanol into divergent synthesis of ethylene glycol and glycolaldehyde concomitantly with H 2 production by structural regulation of atomically dispersed Ni species. We showcase distinctly different reaction pathway for divergent C − C coupling of methanol over two types of atomically dispersed Ni cocatalyst-decorated SiO quantum dots, namely those with single Ni atoms (Ni 1 -SiO/SiO 2 ) and Ni clusters (Ni n -CdS/SiO 2 ). The Ni 1 -CdS/SiO 2 generates ethylene glycol with 90% selectivity by a radical homo-coupling pathway, whereas the Ni n -CdS/SiO 2 achieves 96% selectivity towards glycolaldehyde by a radical addition-elimination pathway. This work not only offers a fascinating nonpetroleum route for the divergent C–C coupling synthesis of ethylene glycol and glycolaldehyde but also underscores the broad vista of modulating non-selective radicals toward selective transformation of methanol into multi-carbon products.