Fu, D., Park, K., Delen, G., Attila, Ö., Meirer, F., Nowak, D., Park, S., Schmidt, JE., Weckhuysen, BM.
Characterizing the structures of zeolites and their catalytic performance with high-spatial-resolution is vital to developing new solid catalysts. We demonstrate the application of photoinduced force microscopy (PiFM), with nanometer scale resolution across the infrared spectral range, for the study of zeolite ZSM-5 thin-films with various...
Li, B., Valverde, LR., Zhang, F., Zhou, Y., Li, S., Diao, Y., Wilson, WL., Schroeder, CM.
One-dimensional (1-D) supramolecular self-assembly offers a powerful strategy to achieve long-range unidirectional ordering of organic semiconducting materials via noncovalent interactions. Using a hierarchical assembly, electronic and optoelectronic materials can be constructed for applications including organic conducting nanowires, organic field-effect transistors (OFETs), and organic light-emitting devices...
Zhang, ZG., Yang, Y., Yao, J., Xue, L., Chen, S., Li, X., Morrison, W., Yang, C., Li, Y.
All-polymer solar cells (all-PSCs) offer unique morphology stability for the application as flexible devices, but the lack of high-performance polymer acceptors limits their power conversion efficiency (PCE) to a value lower than those of the PSCs based on fullerene derivative or organic small molecule acceptors....
Rosu, C., Chu, PH., Tassone, CJ., Park, K., Balding, PL., Park, JO., Srinivasarao, M., Reichmanis, E.
We demonstrate that homopolypeptides covalently tethered to anisotropically shaped silica particles induce crystalline ordering of representative semiconducting polymers. Films drop-cast from chloroform dispersions of poly(γ-stearyl-l-glutamate) (PSLG) composite particles and poly(3-hexythiophene) (P3HT) led to highly ordered crystalline structures of P3HT. Hydrophobic-hydrophobic interactions between the alkyl side...
Schwaighofer, A., Brandstetter, M., Lendl, B.
Quantum cascade lasers (QCL) are the first room temperature semiconductor laser source for the mid-IR spectral region, triggering substantial development for the advancement of mid-IR spectroscopy. Mid-IR spectroscopy in general provides rapid, label-free and objective analysis, particularly important in the field of biomedical analysis. Due...
Qiu, B., Xue, L., Yang, Y., Bin, H., Zhang, Y., Zhang, C., Xiao, M., Park, K., Morrison, W., Zhang, Z., Li, Y.
We synthesized two wide bandgap A–D–A structured p-type organic semiconductor (p-OS) small molecules with weak electron-withdrawing ester end groups: SM1 with cyano group (CN) on the ester group and SM2 without the CN group. SM1 showed stronger absorption, lower-lying HOMO energy level, and higher hole...
Murdick, R., Morrison, W., Nowak, D., Albrecht, T., Jahng, J., Park, S.
Advances in nanotechnology have intensified the need for tools that can characterize newly synthesized nanomaterials. A variety of techniques has recently been shown which combines atomic force microscopy (AFM) with optical illumination including tip-enhanced Raman spectroscopy (TERS), scattering-type scanning near-field optical microscopy (sSNOM), and photothermal...
Peng, P., Cheng, Y., Hatzenbeller, R., Addy, M., Zhou, N., Schiappacasse, C., Chen, D., Zhang, Y., Anderson, E., Liu, Y., Chen, P., Ruan, R.
The non-thermal plasma (NTP) allows the synthesis of ammonia, one of the major hydrogen carriers, at a lower temperature and pressure than the traditional Haber-Bosch process. In this study, we report the synthesis of ammonia using NTP, and a Ru-based, multifunctional catalytic system deposited on...
Ambrosio, A., Devlin, R., Capasso, F., Wilson, W.
Near-field optical microscopy (NSOM) is a scanning probe technique that allows optical imaging of sample surfaces with nanoscale resolution. Generally, all NSOM schemes rely on illuminating the sample surface and collecting the localized scattered light resulting from the interaction of the microscopes nanoscale probe with...
Ruiz, R., Wan, L., Lopez, R., Albrecht, T.
We study the line roughness in poly(styrene-b-methyl methacrylate) symmetric block copolymer thin films and propose a phenomenological model to fit and describe the observed line edge, width, and placement roughness. Owing to the layering structure of symmetric block copolymers, we build from the model used...
Huang, F., Tamma, V., Rajaei, M., Almajhadi, M., Kumar Wickramasinghe, H.
We demonstrate the measurement of laterally induced optical forces using an Atomic Force Microscope (AFM). The lateral electric field distribution between a gold coated AFM probe and a single nano-aperture in a gold film is mapped by measuring the lateral optical force between the apex...
Jacobs, IE., Aasen, EW., Nowak, D., Li, J., Morrison, W., Roehling, JD., Augustine, MP., Moulé, AJ.
Doping-induced solubility control is a patterning technique for semiconducting polymers, which utilizes the reduction in polymer solubility upon p-type doping to provide direct, optical control of film topography and doping level. In situ direct-write patterning and imaging are demonstrated, revealing sub-diffraction-limited topographic features. Photoinduced force...
Jahng, J., Park, S., Morrison, WA., Kwon, H.
When light illuminates the junction formed between a sharp metal tip and a sample, different mechanisms can contribute to the measured photo-induced force simultaneously. Of particular interest are the instantaneous force between the induced dipoles in the tip and in the sample and the force...