Janus Graphene Oxide Nanoparticles for High-Temperature CO ₂ Foam Stabilization: Biparental over a Wide pH Range

This work successfully synthesized a pH-responsive double-sided graphene oxide foam stabilizer (Janus GO-KH560-DETA) through an innovative molecular bridging approach. Its functional groups (amino and carboxyl groups) exhibit reversible protonation–deprotonation behavior under acidic and alkaline conditions, endowing the material with novel and unique pH-responsive properties. Experimental results demonstrated that the Janus GO-KH560-DETA significantly extended foam half-life by 68 min (under ambient conditions) while maintaining stable foam structures across broad pH ranges (3–12) and elevated temperatures (160 °C). The foam stabilization mechanism of the nanoparticles is illustrated in conjunction with molecular dynamics simulations. This graphene oxide solid particle foam stabilizer provides a new way of thinking about the lack of foam stability in harsh fracking environments and offers valuable insights into CO 2 storage and conversion.