1440427-06-4Relevant academic research and scientific papers
Effect of alkyl chain length on the properties of triphenylamine-based hole transport materials and their performance in perovskite solar cells
Fuentes Pineda, Rosinda,Troughton, Joel,Planells, Miquel,Sanchez-Molina Santos, Irene,Muhith, Farmin,Nichol, Gary S.,Haque, Saif,Watson, Trystan,Robertson, Neil
, p. 1252 - 1260 (2018)
A new series of diacetylide-triphenylamine (DATPA) derivatives with five different alkyl chains in the para position, MeO, EtO, nPrO, iPrO and BuO, were synthesised, fully characterised and their function as hole-transport materials in perovskite solar cells (PSC) studied. Their thermal, optical and electrochemical properties were investigated along with their molecular packing and charge transport properties to analyse the influence of different alkyl chains in the solar cell parameters. The shorter alkyl chain facilitates more compact packing structures which enhanced the hole mobilities and reduced recombination. This work suggests that the molecule with the methoxy substituent (MeO) exhibits the best semiconductive properties with a power conversion efficiency of up to 5.63%, an open circuit voltage (Voc) of 0.83 V, a photocurrent density (Jsc) of 10.84 mA cm-2 and a fill factor of 62.3% in perovskite solar cells. Upon replacing the methoxy group with longer alkyl chain substituents without changing the energy levels, there is a decrease in the charge mobility as well as PCE (e.g. 3.29% for BuO-DATPA). The alkyl chain length of semiconductive molecules plays an important role in achieving high performance perovskite solar cells.
Dendritic-Like Molecules Built on a Pillar[5]arene Core as Hole Transporting Materials for Perovskite Solar Cells
Abate, Antonio,Bettucci, Ottavia,Cabrera-Espinoza, Andrea,Collavini, Silvia,Delgado, Juan Luis,K?bler, Hans,Matsuda, Wakana,Nierengarten, Iwona,Nierengarten, Jean-Fran?ois,Pascual, Jorge,Reginato, Gianna,Seki, Shu,Turren-Cruz, Silver-Hamill,V?lker, Sebastian F.
, p. 8110 - 8117 (2021)
Multi-branched molecules have recently demonstrated interesting behaviour as charge-transporting materials within the fields of perovskite solar cells (PSCs). For this reason, extended triarylamine dendrons have been grafted onto a pillar[5]arene core to generate dendrimer-like compounds, which have been used as hole-transporting materials (HTMs) for PSCs. The performances of the solar cells containing these novel compounds have been extensively investigated. Interestingly, a positive dendritic effect has been evidenced as the hole transporting properties are improved when going from the first to the second-generation compound. The stability of the devices based on the best performing pillar[5]arene material has been also evaluated in a high-throughput ageing setup for 500 h at high temperature. When compared to reference devices prepared from spiro-OMeTAD, the behaviour is similar. An analysis of the economic advantages arising from the use of the pillar[5]arene-based material revealed however that our pillar[5]arene-based material is cheaper than the reference.
Diacetylene bridged triphenylamines as hole transport materials for solid state dye sensitized solar cells
Planells, Miquel,Abate, Antonio,Hollman, Derek J.,Stranks, Samuel D.,Bharti, Vishal,Gaur, Jitender,Mohanty, Dibyajyoti,Chand, Suresh,Snaith, Henry J.,Robertson, Neil
, p. 6949 - 6960 (2013/07/26)
We have synthesized and characterized a series of triphenylamine-based hole-transport materials (HTMs), and studied their function in solid-state dye sensitized solar cells (ss-DSSCs). By increasing the electron-donating strength of functional groups (-H -Me -SMe -OMe) we have systematically shifted the oxidation potential and ensuing photocurrent generation and open-circuit voltage of the solar cells. Correlating the electronic properties of the HTM to the device operation highlights a significant energy offset required between the Dye-HTM highest occupied molecular orbital (HOMO) energy levels. From this study, it is apparent that precise control and tuning of the oxidation potential is a necessity, and usually not achieved with most HTMs developed to date for ss-DSSCs. To significantly increase the efficiency of solid-state DSSCs understanding these properties, and implementing dye-HTM combinations to minimize the required HOMO offset is of central importance.
