Proceedings of nanoGe September Meeting 2015 (NFM15)
Publication date: 8th June 2015
Cu2ZnSn(SSe)4 (CZTSSe) in colloidal nanocrystal form is a very interesting multicomponent semiconductor due to high absorption coefficient, earth abundance of the constituent elements, and band-gap tunability. The occurrence of polytypism between the zinc-blende and wurtzite phases in nanocrystals of CZTSSe is a regular feature of their synthesis due to the low energy differential between the two crystal phases. The occurrence of two phases in a single particle can be advantageous for some applications such as thermoelectrics and equally disadvantageous for other applications such as photocatalysis or photovoltaics. To-date there is no control of polytypism in the colloidal synthesis of CZTSSe and also it has not been possible to achieve anisotropic shape control in a particle that is a single crystal to generate the important nanorod form. A systematic understanding of key influential factors to achieve full control over the occurrence of polytypism or elimination is highly desirable for optimization of both the shape and phase of CZTSSe nanocrystals for different applications.
Herein, we show colloidal synthetic approaches to obtain high degree of shape and phase control in the colloidal CZTSSe nanocrystal system. The pivotal role of ligands and metal precursors along with temperature in determining the shape and phase during the nanocrystal growth is demonstrated. We show that under the combined influence of alkylamine and alkylphosphonic ligands, polytypic nanocrystals with wurtzite and zinc-blende phased segments could be achieved. The shape of these polytypic nanocrystals could be tuned by the choice of metal precursors from ellipsoids to arrow-shaped and bullet shaped nanorods. We have also achieved, the formation of pure wurtzite phase 1-D nanorods in a complex quinary system by substituting alkylamine and phosphonic acids with non-coordinating solvent. Preference for 1D growth in these wurtzite nanocrystals is facilitated by adjusting the loading of copper precursor in the initial reaction flask. As CZTSSe is of interest for a range of diverse applications, the ability to control both shape and polytypism at the nanoscale in a colloidal process offers a reproducible route to a wide range of geometries and morphologies that can be optimised as needed.
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.