DOI: https://doi.org/10.29363/nanoge.incnc.2021.064
Publication date: 8th June 2021
A range of optoelectronic and photochemical applications have driven interest in CdS nanocrystals over the last few decades. Of particular note is the use of semiconductor nanocrystals in both photooxidative and photoreductive systems, where the high molar absorptivity of CdS nanocrystals, and the tunable redox potentials of the conduction and valence band can be utilized. In most photoreduction systems using Cd chalcogenide nanocrystals, an external chemical reductant is necessary to generate photocharged states. Here we present an intrinsic photocharging process in CdS nanocrystals without the need for an external reductant. We observe photocharging in CdS nanocrystals across a range of capping ligands, solvent environments, and nanocrystal morphologies. This photocharging process is mediated via hole transfer to the organic surface capping ligand (oleate or octadecyl phosphonate) which then subsequently dissociates. The remaining photoexcited electron persists for many minutes, and the photocharging process is entirely reversible over multiple illumination and recovery cycles. In contrast, nanocrystals with more tightly bound ligands with thiol binding moieties (eg. 3-mercaptopropionate) do not exhibit intrinsic photocharging. This process has significant implications for the photophysical study of CdS nanocrystals, a common model system, as photoreduced states can accumulate even under room lights. However, the long-lived nature of the photoexcited electron also provides a promising avenue for high efficiency electron transfer processes.
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.