Polymer Meets Frustrated Lewis Pair: Second-Generation CO2 -Responsive Nanosystem for Sustainable CO2 Conversion.

Frustrated Lewis pairs (FLP), a couple comprising a sterically encumbered Lewis acid and Lewis base, can offer latent reactivity for activating inert gas molecules. However, their use as a platform for fabricating gas-responsive materials has not yet developed. Merging the FLP concept with polymers, we report a new generation CO2 -responsive system, differing from the first-generation ones based on an acid-base equilibrium mechanism. Two complementary Lewis acidic and basic block copolymers, installing bulky borane- and phosphine-containing blocks, were built as the macromolecular FLP. They can bind CO2 to drive micellar formation, in which CO2 as a cross-linker bridges the block chains. This dative bonding endows the assembly with ultrafast response (<20 s), thermal reversibility, and excellent reproducibility. Moreover, such micelles bound highly active CO2 can function as nanocatalysts for recyclable C1 catalysis, opening a new direction of sustainable CO2 conversion.