A Single-Source Precursor Route to Unusual PbSe Nanostructures by a Solution–Liquid–Solid Method

PbSe nanowires (NWs) have been synthesized by using a single-source precursor route. Carefully controlling the conditions of individual reactions leads to PbSe NWs with well-defined diameters (8–25 nm) and lengths (100 nm–1 μm). The as-grown PbSe NWs are highly crystalline, defect free, and readily dispersible in organic solvents. The NWs have been characterized by X-ray diffraction and high-resolution transmission electron microscopy

A Single-Source Precursor Route to Unusual PbSe Nanostructures by a Solution–Liquid–Solid Method

PbSe nanowires (NWs) have been synthesized by using a single-source precursor route. Carefully controlling the conditions of individual reactions leads to PbSe NWs with well-defined diameters (8–25 nm) and lengths (100 nm–1 μm). The as-grown PbSe NWs are highly crystalline, defect free, and readily dispersible in organic solvents. The NWs have been characterized by X-ray diffraction and high-resolution transmission electron microscopy

Determination of Internal Structures of Heterogeneous Nanocrystals Using Variable-Energy Photoemission Spectroscopy

This article describes the determination of the internal structure of heterogeneous nanoparticle systems including inverted core–shell (CdS core and CdSe shell) and alloyed (CdSeS) quantum dots using depth-resolved, variable-energy X-ray photoelectron spectroscopy (XPS). A unique feature of this work is the combination of photoelectron spectroscopy performed at lower X-ray energies (400–700 eV), to achieve surface sensitivity, with bulk sensitive measurements at high photon energies (>2000 eV), thereby providing detailed information about the whole nanoparticle structure with a great accuracy. The use of high photon energies furthermore allows us to investigate nanoparticles much larger than those studied thus far. This capability is a consequence of the much-increased mean free path of the photoelectron achieved at high excitation energies. Our results show that the actual structures of the synthesized nanoparticles are considerably different from the nominal, targeted structures, which can be post facto rationalized in terms of the reactivity of different constituents