A5030646141- Conducting polymers and applications
- Organic Electronics and Photovoltaics
- Molecular Junctions and Nanostructures
- Fullerene Chemistry and Applications
- Graphene research and applications
- Crystallization and Solubility Studies
- Carbon Nanotubes in Composites
- X-ray Diffraction in Crystallography
- Perovskite Materials and Applications
- Supramolecular Self-Assembly in Materials
- Supercapacitor Materials and Fabrication
- Crystallography and molecular interactions
- Surface Chemistry and Catalysis
- Porphyrin and Phthalocyanine Chemistry
- Advanced battery technologies research
- Nanocluster Synthesis and Applications
- 2D Materials and Applications
- Quantum Dots Synthesis And Properties
- Liquid Crystal Research Advancements
- Organic Light-Emitting Diodes Research
- Spectroscopy and Quantum Chemical Studies
- Polydiacetylene-based materials and applications
- Advanced Thermoelectric Materials and Devices
- Quantum-Dot Cellular Automata
- Photochemistry and Electron Transfer Studies
Columbia University
2017-2021
University of Miami
2015-2017
American Orchid Society
2015-2017
Florida State University
2016
University of Washington
2015
This Communication details the implementation of a new concept for design high-performance optoelectronic materials: three-dimensional (3D) graphene nanostructures. general strategy is showcased through synthesis three-bladed propeller nanostructure resulting from coupling and fusion central triptycene hub helical nanoribbons. Importantly, these 3D nanostructures show remarkable properties that are distinct substituent parts. For example, larger an enhancement in absorption decreased contact...
By storing energy from electrochemical processes at the electrode surface, pseudocapacitors bridge performance gap between electrostatic double-layer capacitors and batteries. In this context, molecular design offers exciting possibility to create tunable inexpensive organic electroactive materials. Here we describe a porous structure composed of perylene diimide triptycene subunits demonstrate its remarkable as pseudocapacitor material. The material exhibits capacitance values high 350 F/g...
Abstract Two cove‐edge graphene nanoribbons hPDI2‐Pyr‐hPDI2 ( 1 ) and hPDI3‐Pyr‐hPDI3 2 are used as efficient electron‐transporting materials (ETMs) in inverted planar perovskite solar cells (PSCs). Devices based on the new exhibit maximum power‐conversion efficiencies (PCEs) of 15.6 % 16.5 for , respectively, while a PCE 14.9 is achieved with devices [6,6]‐phenyl‐C 61 ‐butyric acid methyl ester (PC BM). The interfacial effects induced by these studied using photoluminescence (PL), we find...
Brush polymer patterns, where the position (<italic>x</italic>,<italic>y</italic>), height (<italic>z</italic>), and chemical composition of each feature in an array were controlled independently, prepared by combining massively parallel tip-based photolithography, microfluidics, photochemical radical polymerizations.
We demonstrate nanoscale imaging of charge transfer state photoexcitations in polymer/fullerene bulk heterojunction solar cells using time-resolved electrostatic force microscopy (trEFM). compare local trEFM charging rates and external quantum efficiencies (EQE) for both above-gap below-gap excitation the model system poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) [6,6]-phenyl C61 butyric acid methyl ester (PCBM). show that rate correlates with device EQE...
Supramolecular polymers for solar energy harvesting can be created by considering carefully the relationship between topology, assembly, and photophysics.
Realizing the potential of diketopyrrolopyrrole (DPP) heterocyclic scaffold as a dye or semiconductor in context molecular electronics, organic photovoltaics, and supramolecular chemistry requires understanding fully factors that drive its aggregation. To determine how solubilizing side chains, conjugation length, H‐bonding groups affect DPP assembly into J ‐aggregates, we performed variable temperature ultraviolet–visible titrations toluene on series derivatives. The structures these...
We report that supramolecular polymer films composed of a 2:1 mixture monodiamidopyridine diketopyrrolopyrrole (DPP) electron donors and perylene bisdiimide (PDI) acceptors undergo photoinduced charge transfer in the solid state. Film formation is guided by complementary noncovalent interactions programmed into molecular components, resulting film architecture comprised wires with order across molecular-to-macroscopic continuum. Using ultrafast transient absorption spectroscopy, we show...
Three esters with a perylene, unilaterally, and bilaterally extended perylene core, respectively, were used as emitter materials for organic light-emitting diodes. The electroluminescent properties of these devices studied. Different spectral shifts found, which can be attributed to the formation excited dimers (excimers) in nanofilms materials. Thermal treatment unilaterally derivative resulted red-shift electroluminescence owing denser nanofilm. luminance efficiency optoelectronic...
Nonfullerene electron acceptors have facilitated a recent surge in the efficiencies of organic solar cells, although fundamental studies nature exciton dissociation at interfaces with nonfullerene are still relatively sparse. Semiconducting single-walled carbon nanotubes (s-SWCNTs), unique one-dimensional donors molecule-like absorption and highly mobile charges, provide model system for studying interfacial dissociation. Here, we investigate excited-state photodynamics heterojunction...
The incorporation of nonhexagonal rings into graphene nanoribbons (GNRs) is an effective strategy for engineering localized electronic states, bandgaps, and magnetic properties. Here, we demonstrate the successful synthesis having four-membered ring (cyclobutadienoid) linkages by using on-surface approach involving direct contact transfer coronene-type precursors followed thermally assisted [2 + 2] cycloaddition. resulting coronene-cyclobutadienoid feature a narrow 600-meV bandgap novel...
Abstract Two cove‐edge graphene nanoribbons hPDI2‐Pyr‐hPDI2 ( 1 ) and hPDI3‐Pyr‐hPDI3 2 are used as efficient electron‐transporting materials (ETMs) in inverted planar perovskite solar cells (PSCs). Devices based on the new exhibit maximum power‐conversion efficiencies (PCEs) of 15.6 % 16.5 for , respectively, while a PCE 14.9 is achieved with devices [6,6]‐phenyl‐C 61 ‐butyric acid methyl ester (PC BM). The interfacial effects induced by these studied using photoluminescence (PL), we find...
Atomically precise nanoscale clusters could assemble into crystalline ionic crystals akin to the atomic solids through strong electrostatic interactions between constituent clusters. Here we show that, unlike solids, be frustrated by using large with long and flexible side-chains so that cluster pairs do not crystallize. As such, report superatomic materials can easily solution-processed completely amorphous homogeneous thin-films. These new tunable compositions properties are achievable in...
Semiconducting single-walled carbon nanotubes (s-SWCNTs) are promising materials for solar energy conversion and photodetectors. Fullerenes their derivatives, being widely employed as electron acceptors in s-SWCNT photovoltaic devices, effectively dissociate excitons by forming heterojunctions with favorable energetic offsets. However, limited tunability poor co-processability s-SWCNTs blends have been major obstacles further improving the device performance. Here, we investigate exciton...
Recent interest in potassium-doped p-terphenyl has been fueled by reports of superconductivity at Tc values surprisingly high for organic compounds. Despite these interesting properties, studies the structure-function relationships within materials have scarce. Here, we isolate a phase-pure crystal p-terphenyl: [K(222)]2[p-terphenyl3]. Emerging antiferromagnetism anisotropic structure is studied depth magnetometry and electron spin resonance. Combining experimental results with density...
A strategy is shown for the elongation of graphene nanoribbon (GNR) fragments into air-stable, solution processable and electronically tunable GNRs, aided by incorporating electron-rich donor units between electron-poor oligomeric acceptor units.
Quantitative cross-correlation of time-resolved spectroscopies in the visible/near-IR and microwave regions provides deeper understanding photoinduced charge separation across donor/acceptor heterojunctions than either technique alone.
A hexylalkoxy dipolar D-A-A molecule [7-(4-N,N-(bis(4-hexyloxyphenyl)amino)phenyl)-2,1,3-(benzothia-diazol-4-yl)methylene]propane-dinitrile, (C6-TPA-BT-CN) has been synthesized and the photophysics studied via femtosecond transient absorption spectroscopy (FsTA) in toluene amorphous liquid crystalline spherulite thin films. Two macromolecular phases (banded, non-banded) were observed through concentration dependent, solution processing techniques are birefringent with a negative sign of...
Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been intensively studied in optoelectronic applications due to several advantages such as band gap tunability, high charge carrier mobility, and low internal reorganization energy. However, the fundamental aspects of exciton dissociation at heterojunctions between s-SWCNT electron acceptors still remain elusive. Here, we investigate detailed photodynamics heterojunction (6,5) SWCNTs perylene diimide (PDI) based acceptors. While a...
Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been thoroughly investigated as the components of various photovoltaic cells due to several advantages such spectral tunability, absence charge-transfer (CT) states, giant aspect ratio, chemical robustness, and hydrophobicity. In previous study, it was reported that heterojunctions between s-SWCNTs perylene diimide (PDI)-based electron acceptors yield long-lived charge separated states whose lifetimes are more than 1.5 µs. Besides...