Simple Strategy to Measure the Contact Resistance between Metals and Doped Organic Films

Kirch, Anton; Fischer, Axel; Werberger, Robert; Aabi, Soflaa, Shayan Miri; Maleckaitė, Karolina; Imbrasas, Paulius; Benduhn, Johannes; Reineke, Sebastian

doi:10.1103/physrevapplied.18.034017

Cited by 2 publications

(3 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This could result in the apparent strong carrier density dependence of mobility, which is somewhat alleviated at higher light intensities when the contact resistance at the respective V OC values are significantly reduced. [89] Nonetheless, we point to a close agreement of the range of PM6:Y6 mobilities extracted using IS with those determined by other methods, including SCLC and RPV. [9,17,111]…”

Section: Photoconductance Mobilitysupporting

confidence: 75%

“…Firstly, Equation (11) should only be applied to a trap distribution, but a frequency-varying capacitance is not a unique proof. Therefore, the frequency-dependent reduction in capacitance -for instance due to the contact resistance [89] or dielectric relaxation [90] -may be erroneously attributed to a trap distribution. Secondly, in the case of thin devices diffusion of charges from the electrodes into the AL may result in trap filling, making them insensitive to the electric field modulation.…”

Section: Characterization Of Carrier Trappingmentioning

confidence: 99%

See 1 more Smart Citation

Contemporary Impedance Analyses of Archetypical PM6:Y6 Bulk‐Heterojunction Blend

Tokmoldin,

Deibel,

Neher

et al. 2024

Advanced Energy Materials

View full text Add to dashboard Cite

An organic bulk heterojunction based on a blend of a conjugated polymer PBDB‐T‐2F (PM6) and a non‐fullerene acceptor BTP‐4F (Y6) has come forward in recent years as an archetypical system for the study of the operating principles of organic photovoltaic devices. One of the experimental techniques that has shown immense value in the study of this blend is impedance spectroscopy (IS). In spite of its relative simplicity, this method and its derivatives offer the possibility of diverse, all‐round characterization of materials and devices of interest. This Perspective summarizes recent research demonstrating the application of IS as a powerful method to obtain multifaceted information on PM6:Y6 and presents a current understanding of the experimental results. A description of general approaches employed in the processing of experimental data, including the Nyquist plots, capacitance spectra, and energy‐resolved electrochemical IS data, is supplemented by additional analysis, notably on characterization of non‐geminate recombination of free charge carriers and their transport in this groundbreaking organic blend. Finally, this work outlines the perspectives and limitations of IS in the study of future promising materials and devices.

show abstract

Section: Photoconductance Mobilitysupporting

confidence: 75%

Section: Characterization Of Carrier Trappingmentioning

confidence: 99%

Contemporary Impedance Analyses of Archetypical PM6:Y6 Bulk‐Heterojunction Blend

Tokmoldin,

Deibel,

Neher

et al. 2024

Advanced Energy Materials

View full text Add to dashboard Cite

show abstract

“…Figure B) are kept constant to exclude spectral shifts due to a changing optical cavity effect. Second, doped layers ensure both a low injection and transport resistance at reasonable driving conditions as investigated in a recent study from our lab . As a result, much of the applied bias can be expected to drop over the D–A interface at low forward bias, producing a significant extrinsic electric field F ex (cf.…”

Section: Conceptionmentioning

confidence: 99%

Tuning Charge-Transfer States by Interface Electric Fields

Kirch,

Wolansky,

Miri Aabi Soflaa

et al. 2024

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

Intermolecular charge-transfer (CT) states are extended excitons with a charge separation on the nanometer scale. Through absorption and emission processes, they couple to the ground state. This property is employed both in light-emitting and light-absorbing devices. Their conception often relies on donor−acceptor (D−A) interfaces, so-called type-II heterojunctions, which usually generate significant electric fields. Several recent studies claim that these fields alter the energetic configuration of the CT states at the interface, an idea holding prospects like multicolor emission from a single emissive interface or shifting the absorption characteristics of a photodetector. Here, we test this hypothesis and contribute to the discussion by presenting a new model system. Through the fabrication of planar organic p-(i-)n junctions, we generate an ensemble of oriented CT states that allows the systematic assessment of electric field impacts. By increasing the thickness of the intrinsic layer at the D−A interface from 0 to 20 nm and by applying external voltages up to 6 V, we realize two different scenarios that controllably tune the intrinsic and extrinsic electric interface fields. By this, we obtain significant shifts of the CT-state peak emission of about 0.5 eV (170 nm from red to green color) from the same D−A material combination. This effect can be explained in a classical electrostatic picture, as the interface electric field alters the potential energy of the electric CT-state dipole. This study illustrates that CT-state energies can be tuned significantly if their electric dipoles are aligned to the interface electric field.

show abstract

Simple Strategy to Measure the Contact Resistance between Metals and Doped Organic Films

Cited by 2 publications

References 51 publications

Contemporary Impedance Analyses of Archetypical PM6:Y6 Bulk‐Heterojunction Blend

Contemporary Impedance Analyses of Archetypical PM6:Y6 Bulk‐Heterojunction Blend

Tuning Charge-Transfer States by Interface Electric Fields

Contact Info

Product

Resources

About