Publication date: 27th June 2014
For over 30 years semiconductor nanocrystals (NCs) have been the subject of much interest for fundamental and applied studies. The synthesis of NCs has developed and matured over this time such that production of monodisperse, photostable NCs with close to an exact size and shape are readily achievable. However, an understanding of the chemical reaction mechanism behind the synthesis of NCs has lagged the ability to synthesize high quality nanoparticles. In this presentation, NC synthetic mechanisms that have been proposed for metal-chalcogenide (ME) semiconductor NCs, particularly CdE and PbE, will be discussed. Specifically, for PbE NCs synthesized under relatively low temperatures (< 200 ºC) it was found that secondary phosphine chalcogenides are the primary reactive species that determines the formation of NC nuclei. Tertiary phosphine chalcogenides are completely unreactive at these temperatures. Small quantities of secondary phosphine impurities in the conventional tertiary phosphine based synthesis thus play an important role in determining the number of NCs formed and the rates of the reaction. For NCs synthesized under much higher temperatures (generally > 250 ºC), such as CdE NCs, several other mechanistic pathways start to dominate the reactivity. In particular, strong evidence exists for the formation of highly reactive metal-alkyl species in situ, which fundamentally bears a striking resemblance to some of the original CdSe NC syntheses developed over 20 years ago. Also to be discussed will be how an understanding of fundamental reaction mechanism can lead to improved NCs with controllable surface chemistry and with tailored optical properties.
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.