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An ionic liquid, 1-methyl-3-propylimidazolium iodide (MPII), was solidified with an organic hole-transporting material, 4,4′,4″-tris[(3-methylphenyl)phenylamino]triphenylamine (m-MTDATA), and the resulting solid-state redox mediator (RM) (m-MTDATA-solidified MPII) was employed in solar devices to realize solid-state dye-sensitized solar cells (sDSSCs). Solar devices with only MPII or m-MTDATA as an RM showed almost 0 mA/cm2 of short-circuit current (Jsc) and thus 0% power conversion efficiency (PCE). However, an sDSSC with the m-MTDATA-solidified MPII exhibited 4.61 mA/cm2 of Jsc and 1.80% PCE. It was found that the increased Jsc and PCE were due to the formation of I3−, which resulted from a reaction between the iodie (I−) of MPII and m-MTDATA cation. Further enhancement in both Jsc (9.43 mA/cm2) and PCE (4.20%) was observed in an sDSSC with 4-tert butylpyridine (TBP) as well as with m-MTDATA-solidified MPII. We attributed the significant increase (about 230%) in PCE to the lowered diffusion resistance of I−/I3− ions in the solid-state RM composed of the m-MTDATA-solidified MPII and TBP, arising from TBP's role as a plasticizer. [ABSTRACT FROM AUTHOR]

Abstract: A light‐driven deformable mirror based on an organic photoconductive layer is designed and realized. The requirements for the photoconductive organic material are reported showing their effect on the mirror performances. The production and characterization of the photoconductive thick layer consisting in a polystyrene matrix doped with P3HT:PCBM and an arylamine (4,4′,4″‐tris[phenyl(m‐tolyl)amino]triphenylamine) are reported. A prototype of the mirror with a clear aperture of 12 mm is built and its performance measured in terms of reflective surface displacement. Moreover, a light valve device based on this mirror is built and characterized. [ABSTRACT FROM AUTHOR]

Abstract: To overcome the drawbacks of the acidic and hygroscopic nature of the poly(3,4‐ethylenedio‐xythiophene):poly(styrenesulfonate) hole transport layer (HTL), the p‐type polymeric hole transport materials have attracted great attention and have been applied into perovskite solar cells. Here, a starburst amine molecule 4,4′,4″‐tris(3‐methylphenylphenylamino)triphenylamine (m‐MTDATA) without any additive is demonstrated as an effective hole transport material in perovskite solar cells. Meanwhile, considering the different surface affinity of precursor's composition on m‐MTDATA, the influence of the molar ratios between lead iodine (PbI2) and methylammonium iodide in precursor solution on the perovskite characteristics and device performance is investigated in‐depth. Ultimately, an enhanced efficiency of 17.73% and a high fill factor of 79.6% are achieved, which attribute to the strong passivation effect of traps and small resistance loss from appropriate unreacted PbI2 left in the perovskite layer. This work not only provides a remarkable HTL, but also reveals that the adjustment of precursor ratio is necessary for the one‐step solution approach, because the affinities of precursor's composition may be different with the underlying transport layers. [ABSTRACT FROM AUTHOR]

Abstract: We found that a 1:1 volume ratio mixed film formed by co-evaporation of 4,4,4-tris(N-3-methylphenyl-N-phenylamino) triphenylamine (m-MTDATA) and copper hexadecafluorophthalocyanine (F16CuPc) showed a board optical absorption band from 900 to 1500nm not observed from the two constituting materials. The new IR absorption band is attributed to the charge-transfer complex formed by electron transfer from m-MTDATA to F16CuPc upon intimate contact. By using the mixed film as an active layer, we demonstrate an organic photovoltaic device (OPV) which can generate electric power from photons with longer than 1300nm wavelength. [Copyright &y& Elsevier]

An electrically conducting amorphous molecular material was prepared by iodine doping of 4,4′,4″-tris[3-methylphenyl(phenyl)amino]triphenylamine (m-MTDATA). The use of iodine-doped m-MTDATA, which was identified as m-MTDATA radical cation species with counter anions, as a hole-injection buffer layer in tris(8-quinolinolato)aluminum (Alq 3 )-based organic electroluminescent devices led to the reduction of drive voltage and the enhancement of external quantum efficiency as compared with the corresponding device using undoped m-MTDATA. It is indicated that the use of iodine-doped m-MTDATA facilitates not only hole injection from the ITO electrode but also electron injection from the cathode into Alq 3 . [ABSTRACT FROM AUTHOR]

Organic thin film materials are widely investigated for applications in electronic and optoelectronic devices. For OLEDs with low operation voltage, controlled doping of the charge transport layers is particularly important. We have recently shown that starburst like amorphous materials (m-MTDATA) can be doped by strong molecular acceptors like F4-TCNQ (tetrafluoro-tetracyano-quinodimethane). These amorphous materials have the advantage of being stable up to 100 °C and forming smooth surfaces. Very well blocking Mip-type Schottky structures (rectification ratio 104–105) allow to determine doping profiles using CV (capacitance–voltage) spectroscopy. The interface between the doped and the undoped layer can be clearly seen as an abrupt change of the capacitance. The impedance spectra can be understood in terms of an equivalent circuit model. The deduced parameters agree well with the nominal thicknesses of the i- and the p-layer and the independently measured bulk conductivity. [Copyright &y& Elsevier]

We performed a spectroscopic study on the m -MTDATA (donor) and PPT (acceptor) molecular vertical heterostructure. The electronic properties of the donor/acceptor interface have been comprehensively characterized by synchrotron radiation-based photoelectron spectroscopy and near-edge x-ray absorption fine structure. The spectroscopic results reveal the existence of new hybridization states in the original molecular energy gap, likely attributed to the interaction between the donor and the acceptor molecules at the interface. Such hybridized states can have a significant impact on the charge transport in organic electronic devices based on donor-acceptor molecules and can explain the increased efficiency of device using such molecules., (© 2022 IOP Publishing Ltd.)

Abstract: This letter reports efficiency improvements in single-heterojunction organic photovoltaic (OPV) cells exploiting different wide-bandgap electron-blocking layer (EBL) materials of N,N,NO’,N’ tetrakis(4-methoxyphenyl)-benzidine (MeO-TPD), Tris(phenypyrazole)iridium (Ir(ppz)3), or 4,4,4”-tris-(3-methylphenylphenylamino)triphenylamine (m-MTDATA), respectively. The OPV structure consists of an indium–tin-oxide (ITO) anode, 4nm m-MTDATA, 30nm copper phthalocyanine (CuPc), 40nm fullerene (C60), 10nm 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), and a 100nm Al cathode. Optimum device performances by insertion the EBL of m-MTDATA have been achieved, including short-circuit current density (J SC) of 7.26mA/cm2, open-circuit voltage (V OC) of 0.5V, fill-factor (FF) of 43%, and power conversion efficiency (PCE) of 1.56% at an illumination intensity of 100mW/cm2. [Copyright &y& Elsevier]