CdSe 1D/2D Mixed‐Dimensional Heterostructures: Curvature‐Complementary Self‐Assembly for Enhanced Visible‐Light Photocatalysis

Abstract

Mixed‐dimensional heterostructures (MDHs), which combine nanomaterials of different dimensionalities deliver on the promise to bypass intrinsic limitations of a given low‐dimensional material. Here, a strategy to engineer MDHs between two low‐dimensional materials by curvature‐complementary self‐assembly is described. CdSe nanotubes rolled from 2D nanosheets and 1D CdSe nanorods, with negative and positive curvatures, respectively, are selected to illustrate complementary curvature self‐assembly. The assembly process, optical, and photoelectrical properties of the CdSe MDHs are thoroughly investigated. Several remarkable features of CdSe MDHs, including increased light absorption, efficient charge separation, and appropriate bandgap structure are confirmed. The MDHs significantly alleviate the sluggish kinetics of electron transfer in the quantum sized CdSe subunits (onset potential of 0.21 V vs RHE for MDHs; 0.4 V lower than their low‐dimensional building blocks), while the spatial nano‐confinement effect in the CdSe MDHs also assists the interfacial reaction kinetics to render them ideal photocatalysts for benzylamine oxidation (conversion > 99% in 4 h with a two times higher rate than simple mixtures). The results highlight opportunities for building MDHs from low‐dimensional building blocks with curvature‐complementary features and expand the application spectrum of low dimensional materials in artificial photosynthesis.

Chiral superstructures of inorganic nanorods by macroscopic mechanical grinding

“…CdSe NRs were synthesized based on a previous report 39 , 41 . CdSe NRs capped with TOP, TOPO, TDPA, and TBP were synthesized using a Schlenk-line.…”

Encapsulated CdSe/CdS nanorods in double-shelled porous nanocomposites for efficient photocatalytic CO2 reduction

“…Hence, imparting porosity, especially for hierarchical pores ranging from micropores to mesopores, into the QDs solids would overcome the gas diffusion-limited issue. Packing of QDs into non-close-packed (NCP) structure in confined medium could be one of the possible solutions, but it requires precise design of colloidal building blocks 29 , 30 . The development of reticular chemistry enables the synthesis of metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), and porous organic cages (POCs), which potentially provides diversified yet robust porous scaffolds hosting the QDs solids 31 – 35 .…”

Ag-Doped CdSe Nanosheets as Photocatalysts for Uranium Reduction

“…For example, Wei et all. assembled two-site nanosheets with negative curvature and one-dimensional CdSe nanorods with positive curvature to adjust the band gap structure of CdSe to form a hybrid dimensional heterojunction material . Khalaf et al successfully grew CdSe nanocrystals on glass substrates by plasma sputtering with film thicknesses ranging from 350 to 600 nm and found that the optical band gap decreases with increasing sample size …”