Emulsion Droplet Microreactors for Efficient Heterogeneous Photoreforming Hydrogen Evolution

Abstract Photocatalytic reforming bio‐alcohols H 2 evolution is favorable for green sustainability. Pickering emulsions (PEs) provide multiple microreactor systems for heterogeneous catalysis. However, some key factors on interfacial mass transfer and reaction kinetics are limited. This work developed a series of TiO 2 /MWCNTs (TCN)‐stabilized PEs for interfacial photoreforming hydrogen (H 2 ) evolution. TCN composite connected through ester bonds and electrostatical attraction reduced interfacial tension of H 2 O‐n‐Octanol system, enhancing stability of PEs. Electrons transferred from TiO 2 to MWCNTs at PEs interfaces via DFT calculations. The optimal photoreforming H 2 production amount with TCN (3%) stabilized PEs reached 3991.8 µmol g −1 after 3 h, which is 9.93 times higher than that of TiO 2 in single water (401.8 µmol g −1 ). The apparent quantum yield of TCN (3%) stabilized PEs is 5.2 times higher than that of an oil‐water mixture. Under the necessity of stability, PE interfaces facilitated the transport of active species, promoting efficient H 2 production and partial organic oxidation while improving mass transfer and reaction kinetics. This study provides valuable theoretical insights into enhanced photoreforming reactions in liquid‐liquid heterogeneous systems and potential for reutilizing biomass derivatives.