Bidirectional and reversible tuning of the interlayer spacing of two-dimensional materials

Interlayer spacing is expected to influence the properties of multilayer two-dimensional (2D) materials. However, the ability to non-destructively regulate the interlayer spacing bidirectionally and reversibly is challenging. Here we report the preparation of 2D materials with tunable interlayer spacing by introducing active sites (Ce ions) in 2D materials to capture and immobilize Pt single atoms. The strong chemical interaction between active sites and Pt atoms contributes to the intercalation behavior of Pt atoms in the interlayer of 2D materials and further promotes the formation of chemical bonding between Pt atom and host materials. Taking cerium-embedded molybdenum disulfide (MoS2) as an example, intercalation of Pt atoms enables interlayer distance tuning via an electrochemical protocol, leading to interlayer spacing reversible and linear compression and expansion from 6.546 +/- 0.039 angstrom to 5.792 +/- 0.038 angstrom (similar to 11 %). The electronic property evolution with the interlayer spacing variation is demonstrated by the photoluminescence (PL) spectra, delivering that the well-defined barrier between the multilayer and monolayer layered materials can be artificially designed. Modifying the interlayer spacing in two-dimensional materials is an effective approach to tune their chemical and physical properties. Here the authors report that intercalation of Pt atoms into cerium-doped MoS2 enables adjusting the interlayer spacing bidirectionally and reversibly.

Automated summary

The ability to tune the interlayer spacing bidirectionally and reversibly in 2D materials by introducing active sites (Ce ions) to capture and immobilize Pt single atoms has been demonstrated in this study. Taking cerium-embedded molybdenum disulfide (MoS2) as an example, intercalation of Pt atoms enabled reversible and linear compression and expansion of the interlayer spacing. This approach offers a potentially effective way to modify the chemical and physical properties of two-dimensional materials.