6 research outputs found
Integrating metalloporphycenes into p-type NiO-based dye-sensitized solar cells
In the current work, we have explored a novel synthetic route towards metalated porphycenes and their use in p-type NiO-based dye-sensitized solar cells. Particular emphasis is placed on the influence that the relative positioning of the anchoring group exerts on the DSSC performance
Controlling Interfacial Charge Transfer and Fill Factors in CuO-based Tandem Dye-Sensitized Solar Cells
We designed and synthesized a series of novel electron-accepting zinc(II)phthalocyanines (ZnPc) and probed them in p-type dye sensitized solar cells (p-DSSCs) by using CuO as photocathodes. By realizing the right balance between interfacial charge separation and charge recombination, optimized fill factors (FFs) of 0.43 were obtained. With a control over fill factors in p-DSSCs in hand we turned our attemtion to t-DSSCs, in which we combined for the first time CuO-based p-DSSCs with TiO 2 -based n-DSSCs using ZnPc and N719. In the resulting t-DSSCs, the V OC of 0.86 V is the sum of those found in p- and n-DSSCs, while the FF remains around 0.63. It is only the smaller J sc s in t-DSSCs that limits the efficiency to 0.69 %We thank the German Science Council (DFG) for the 51 financial support in the framework of the Cluster of 52 Engineering of Advanced Materials (EAM). Furthermore, 53 we are grateful for the financial support of the MINECO, 54 Spain (Grant CTQ2017-85393-P), and the Comunidad de 55 Madrid, Spain (FOTOCARBON, S2013/MIT-2841). 56 IMDEA-Nanociencia acknowledges support from the 57 “Severo Ochoa” Program for Centres of Excellence in 58 R&D (MINECO, Grant SEV-2016-0686). R.D.C. acknowledges the Ramn y Cajal program “Spanish MINECO (RYC2 2016–20891)
Improving charge injection and charge transport in CuO-based p-type DSSCs-a quick and simple precipitation method for small CuO nanoparticles
Herein, we introduce a co-precipitation synthesis of CuO, which produces small and uniform nanoparticles (∼12 nm) with a specific surface area of 97.3 m2g-1. The resulting CuO nanoparticles are superior to the commercial ones, which have previously been used to prepare p-type DSSCs. In turn, we compared p-type DSSCs consisting of CuO-based photocathodes based on newly synthesized and commercial nanoparticles. Devices based on new CuO nanoparticles enable higher dye loadings, and, in turn, superior short-circuit current densities and efficiencies. To corroborate our findings, electrochemical impedance spectroscopy and intensity modulated photocurrent spectroscopy assays were conducted, revealing a better charge injection and faster charge transport for those photocathodes featuring the new CuO nanoparticlesThe authors thank the German Science Council (DFG) for the
financial support in the framework of the Cluster of Engineering
of Advanced Materials (EAM). O.Langmar thanks S. Romeis for
the BET measurement
Optimizing CuO p-type dye-sensitized solar cells by using a comprehensive electrochemical impedance spectroscopic study
We introduce a novel and comprehensive approach for the evaluation and interpretation of electrochemical impedance spectroscopy (EIS) measurements in p-type DSSCs. In detail, we correlate both the device performance and EIS figures-of-merit of a series of devices in which, the calcination temperature, film thickness, and electrolyte concentration have been systematically modified. This new approach enables the separation of the different processes across the dye/semiconductor/electrolyte interface, namely the unfavorable charge recombination and the favorable electron injection/regeneration processes. In addition, studies on non-sensitized CuO and NiO electrodes provide insights into their affinity towards a reaction with the electrolyte – CuO is far less reactive towards the polyiodide species. Overall, this work underlines the superior features of CuO with respect to NiO for p-DSSCs and demonstrates a comprehensive optimization of the CuO-based DSSCs with respect to the device architecture by the aid of EIS analysis