Investigating the Third‐Order NLO Performance of a Three‐Phase Core‐Shell PANI@MIL‐101(Cr)@CeO₂ with Internal and External Synergies

Abstract Combining metal–organic frameworks (MOFs) with other functional materials can effectively improve the third‐order nonlinear optical (NLO) performances of MOFs. In this study, two distinct functional materials are selected and a PANI@MIL‐101(Cr)@CeO₂ composite is successfully synthesized. The test results of third‐order NLO indicate that introducing PANI regulates the distribution of π electron clouds within the structure of the composite. Additionally, the core@shell structure formed by PANI@MIL‐101(Cr) and CeO₂ promotes charge transfer and improves charge transfer efficiency under the weak heterojunction interaction, thereby enhancing nonlinear absorption and refractive signals. Under the double synergistic action of interior and exterior, a new charge transfer occurs between the components of the composite, resulting in excellent third‐order NLO performances. This study indicates that encapsulating polymer and loading metal oxides can effectively improve the NLO response of MOFs, which offers a new idea for more research on multiphase NLO materials.