Inspired by natural creatures, bubble manipulation by surface microstructures in aqueous media has attracted great attention due to its promising applications in industrial production. Herein, a superhydrophobic/hydrophilic Janus aluminum membrane with tapered micropore arrays was fabricated by femtosecond laser drilling, surface fluorination, and subsequent fluorination removal. Compared with the single interception or penetration of double-faced hydrophilic or superhydrophobic membranes, the Janus membrane showed a distinctive unidirectional air bubble transport ability. In experiment, the air bubbles introduced on the lower hydrophilic surface could spontaneously move to the upper superhydrophobic surface, but they were prevented in the inverse direction. The dynamic process of unidirectional transport was in-situ monitored, and the physical mechanism was systemically investigated. In addition, the concepts of air-participating chemical/physical processes were demonstrated such as discoloration of purple litmus solution by CO2 injection, which proved the Janus membrane practicability.

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Cataluminescence is an attractive oxydic luminescence on the gas–solid interface, and metal-oxide@MOF core@shell architectures show great potential for cataluminescence sensing due to their integrated synergistic effect from core and shell components. However, restricting the direct nucleation and growth of metal–organic frameworks (MOFs) on the topologically distinct surface of metal oxides is a great challenge, owing to the high interface energy from the topology mismatch. Herein, for the first time, a novel liquid-phase concentration-controlled nucleation strategy is exploited to induce the direct assembly of a ZIF-8 layer on the surface of CeO2 nanospheres without any sacrificial templates or further surface modifications. The results show that the construction of the CeO2@ZIF-8 core@shell architecture can be accomplished within 1 min under the mediation of boosted nucleation kinetics. Furthermore, the universality of this developed strategy is demonstrated by the encapsulation of other metal-oxide cores such as magnetic Fe3O4 and ZnCo2O4 core particles with a ZIF-8 shell. Notably, compared to the pure CeO2 and ZIF-8, the obtained CeO2@ZIF-8 nanocomposite exhibits enhanced analytical performance for the cataluminescence sensing of propanal, in which the shell acts as the major catalytic reaction center, while the core contributes to further improving the catalytic efficiency. The proposed facile synthesis strategy with excellent simplicity, rapidity, and universality brings new insights into the engineering of core@shell advanced functional materials with mismatched topologies for catering to the diverse application demands.

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