Controlling placement of quantum states in phosphorene nanoribbons using ligands
Not provided.
Chemistry↗
Engineering topics
Lambert, Ryan
Publications and source records attributed to Lambert, Ryan.
Transforming the electronic properties of phosphorene through charge transfer superatomic doping
Phosphorene is a two-dimensional electron poor p-type semiconductor with great promise for applications in electronics and optoelectronics. Here, in this work, we propose how the two most important properties of a semiconductor, the band gap energy and the nature of carriers, can be controlled by changing the dimensionality or through charge transfer doping with metal-chalcogenide superatoms. Our studies on nanoribbons examine how the band gap can be changed by controlling the width of the ribbons. We investigate the stability and properties of bare and H-terminated nanoribbons. We show that small non-passivated ribbons can be metallic while the passivated ribbons show variation in the band gap energy as a function of the width of the ribbon. We next investigate an alternative approach to band gap and carrier control via doping with ligated metal-chalcogenide superatom clusters whose redox properties can be changed by ligand exchange. Our results obtained from deposition of Co 6 S 8 (PH 3 ) 5-n (CO) n clusters on a phosphorene support showed that the band gap energy can be controlled by exchanging the electron donating phosphine ligands with electron withdrawing CO. We then show that by depositing Re 6 Se 8 (PH 3 ) 5-n Cl n clusters, phosphorene can be converted into a p- or n- type semiconductor as the relative composition of ligands is changed. Our studies provide a novel approach to controlling carrier type and band gap in phosphorene.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
The superatomic state beyond conventional magic numbers: Ligated metal chalcogenide superatoms
The field of cluster science is drawing increasing attention due to the strong size and composition-dependent properties of clusters and the exciting prospect of clusters serving as the building blocks for materials with tailored properties. However, identifying a unifying central paradigm that provides a framework for classifying and understanding the diverse behaviors is an outstanding challenge. One such central paradigm is the superatom concept that was developed for metallic and ligand-protected metallic clusters. The periodic electronic and geometric closed shells in clusters result in their properties being based on the stability they gain when they achieve closed shells. This stabilization results in the clusters having a well-defined valence allowing them to be classified as superatoms – thus, extending the periodic table to a third dimension. This perspective focuses on extending the superatomic concept to ligated metal-chalcogen clusters that have recently been synthesized in solutions and form assemblies with counterions that have wide-ranging applications. Here we illustrate that the periodic patterns emerge in the electronic structure of ligated metal-chalcogenide clusters. The stabilization gained by the closing of their electronic shells allows for the prediction of their redox properties. Further investigations reveal how the selection of ligands may control the redox properties of the superatoms. These ligated clusters may serve as chemical dopants for two-dimensional semiconductors to control their transport characteristics. Superatomic molecules of multiple metal-chalcogen superatoms allow for the formation of nano pn junctions ideal for directed transport and photon harvesting. As a result, the perspective outlines future developments, including the synthesis of magnetic superatoms.
36 MATERIALS SCIENCE↗