Microstructured gas-liquid-(solid) interfaces: A platform for sustainable synthesis of commodity chemicals.

Gas-liquid-solid catalytic reactions are widespread in nature and man-made technologies. Recently, the exceptional reactivity observed on (electro)sprayed microdroplets, in comparison to bulk gas-liquid systems, has attracted the attention of researchers. In this perspective, we compile possible strategies to engineer catalytically active gas-liquid-(solid) interfaces based on membrane contactors, microdroplets, micromarbles, microbubbles, and microfoams to produce commodity chemicals such as hydrogen peroxide, ammonia, and formic acid. In particular, particle-stabilized microfoams, with superior upscaling capacity, emerge as a promising and versatile platform to conceive high-performing (catalytic) gas-liquid-(solid) nanoreactors. Gas-liquid-(solid) nanoreactors could circumvent current limitations of state-of-the-art multiphase reactors (e.g., stirred tanks, trickle beds, and bubble columns) suffering from poor gas solubility and mass transfer resistances and access gas-liquid-(solid) reactors with lower cost and carbon footprint.