Functional polyelectrolyte nanospaced MoS2 multilayers for enhanced photoluminescence.

Molybdenum disulfide (MoS2) multilayers with functional polyelectrolyte nanospacing layers are presented. Taking advantage of the facile method of layer-by-layer (LbL) assembly, individual chemically exfoliated MoS2 layers are not only effectively isolated from interlayer coupling but also doped by functional polymeric layers. It is clearly demonstrated that MoS2 nanosheets separated by polymeric trilayers exhibit a much larger increase in photoluminescence (PL) as the number of layers is increased. The enhanced PL has been correlated to the ratio of excitons to trions with the type of polymeric spacers. Because uniform heterogeneous interfaces can be formed between various transition metal dichalcogenides and other soft materials, LbL assembly offers possibilities for further development in the solution-processable assemblies of two-dimensional materials.