Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV18)
Publication date: 21st February 2018
Given the greater chemical tunability of non-fullerene acceptors, a promising strategy towards increasing the open-circuit voltage in organic solar cells consists of reducing donor and acceptor energy level offsets. However, this approach could result in opening an additional recombination channel for the charge-transfer (CT) complex via a lower-lying polymer triplet level. Competition between this so-called electron back-transfer (EBT) process and charge dissociation will be detrimental to the overall device performance and energetic alignment between the donor and acceptor should be tailored to suppress EBT losses.
Our research interest towards small-molecule acceptors based on the dithienylthiazolo[5,4-d]thiazole (DTTzTz) structural motif was driven by its strong electron-accepting character and efficient π-π stacking, allowing for high mobilities, as observed in donor polymers based on this unit [1]. Although efficient CT in low-driving force blends of a series of DTTzTz acceptors with MDMO-PPV and P3HT could be established by nearly complete photoluminescence quenching, device performance in these systems was particularly poor, with power conversion efficiencies of <0.1% [2]. Hence, in order to understand the low device efficiencies, the formation of triplets and polarons after CT was studied by means of photo-induced absorption (PIA) and doping-induced absorption spectroscopy to assess the role of EBT in these systems. Strong signatures of efficient polymer triplet level population in PIA support the identification of EBT as a dominant loss mechanism in MDMO-PPV:diCN-DTTzTz blends. The work especially focuses on the distinction between spectroscopic signatures from triplet and polaronic species in PIA experiments.
References:
[1] I. Osaka et al., Chem. Mater. 22 (2010) 4191.
[2] N. Nevil et al., Phys. Chem. Chem. Phys. 14 (2012) 15774.
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.