A5031911852- Organic Electronics and Photovoltaics
- Machine Learning in Materials Science
- Conducting polymers and applications
- Innovative Microfluidic and Catalytic Techniques Innovation
- Perovskite Materials and Applications
- Scientific Computing and Data Management
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Organic and Molecular Conductors Research
- Computational Drug Discovery Methods
- Luminescence and Fluorescent Materials
- Organic Light-Emitting Diodes Research
- Crystallography and molecular interactions
- Quantum, superfluid, helium dynamics
- Oxidative Organic Chemistry Reactions
- Fullerene Chemistry and Applications
- Molecular Junctions and Nanostructures
- Advanced Materials Characterization Techniques
- Mobile Crowdsensing and Crowdsourcing
- Advanced Photocatalysis Techniques
- Chalcogenide Semiconductor Thin Films
- Microfluidic and Capillary Electrophoresis Applications
- Atomic and Subatomic Physics Research
- Photochemistry and Electron Transfer Studies
- Advanced NMR Techniques and Applications
North Carolina State University
2023-2024
University of Toronto
2021-2024
Future Earth
2024
University of California, Santa Barbara
2017-2024
University of Southern California
2014-2022
Santa Barbara City College
2017-2020
University of California System
2017
Southern California University for Professional Studies
2015
Los Angeles City College
2015
Helium nanodroplets are considered ideal model systems to explore quantum hydrodynamics in self-contained, isolated superfluids. However, exploring the dynamic properties of individual droplets is experimentally challenging. In this work, we used single-shot femtosecond x-ray coherent diffractive imaging investigate rotation single, superfluid helium-4 containing ~10(8) 10(11) atoms. The formation vortex lattices inside confirmed by observing characteristic Bragg patterns from xenon clusters...
Narrow bandgap n-type molecular semiconductors are relevant as key materials components for the fabrication near-infrared organic solar cells (OSCs) and photodetectors (OPDs). We thus designed nearly isostructural nonfullerene electron acceptors, except choice of solubilizing units, which absorb from 600 to 1100 nm. Specific molecules include CTIC-4F, CO1-4F, COTIC-4F, whose optical bandgaps 1.3, 1.2, 1.1 eV, respectively. Modulation intramolecular charge transfer characteristics was...
We must accelerate the pace at which we make technological advancements to address climate change and disease risks worldwide. This swifter of discovery requires faster research development cycles enabled by better integration between hypothesis generation, design, experimentation, data analysis. Typical take months years. However, data-driven automated laboratories, or self-driving can significantly molecular materials discovery. Recently, substantial have been made in areas machine...
Contemporary materials discovery requires intricate sequences of synthesis, formulation, and characterization that often span multiple locations with specialized expertise or instrumentation. To accelerate these workflows, we present a cloud-based strategy enabled delocalized asynchronous design-make-test-analyze cycles. We showcased this approach through the exploration molecular gain for organic solid-state lasers as frontier application in optoelectronics. Distributed robotic synthesis...
Abstract Two narrow bandgap non‐fullerene acceptors (NBG‐NFAs), namely, COTIC‐4F and SiOTIC‐4F, are designed synthesized for the fabrication of efficient near‐infrared organic solar cells (OSCs). The chemical structures NBG‐NFAs contain a D′‐D‐D′ electron‐rich internal core based on cyclopentadithiophene (or dithienosilole) (D) alkoxythienyl (D′) core, end‐capped with highly electron‐deficient unit 2‐(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐inden‐1‐ylidene)malononitrile (A), ultimately providing...
Abstract In this work, the way in which ambient moisture impacts photovoltaic performance of conventional PCBM and emerging polymer acceptor–based organic solar cells is examined. The device two representative p‐type polymers, PBDB‐T PTzBI, blended with either or polymeric acceptor N2200, systemically investigated. both cases, all‐polymer devices processed from high‐humidity conditions exhibit significantly enhanced moisture‐tolerance compared to their polymer–PCBM counterparts. impact on...
Abstract The photovoltaic and electrical properties of organic semiconductors are characterized by their low dielectric constant, which leads to the formation polarons Frenkel excitons. constant has been suggested be significantly influential in geminate bimolecular recombination losses photovoltaics (OPVs). However, despite critical attention that received literature discussions, there not yet a thorough study common how it changes when blended. In fact, have some inconsistent contradictory...
Abstract Two conjugated oligoelectrolytes (COEs), WMG1 and WMG2, were designed with the goal of achieving near infrared absorption high photothermal conversion efficiency. Specifically, electron‐rich thiophene electron‐poor benzo[1,2‐c:4,5‐c′]bis[1,2,5]thiadiazole subunits introduced into core to modulate optical gap reduce fluorescence emission WMG2 show maxima at around 800 nm, which favors tissue penetration. Although relatively small in size, exhibit efficiencies circa 60 % 54 %,...
Abstract A series of narrow bandgap electron acceptors is designed and synthesized for efficient near‐infrared (NIR) organic solar cells. Extending π‐conjugation donor frameworks leads to an intense intramolecular charge transfer, resulting in broad absorption profiles with band edge reaching 950 nm. When blended polymer PTB7‐Th, IOTIC‐2F exhibits transfer even a small energetic offset, so as achieve large photogenerated current over 22 mA cm −2 energy losses (≈0.49 eV) cell devices. With...
Semiconducting polymers provide a ubiquitous platform for range of applications in molecular electronics and photovoltaics, but the ordered disordered regions these materials impart different optoelectronic properties. By resolving local morphology using solid-state magnetic resonance spectroscopy modeling techniques, here, we demonstrate that PTB7-Th donor–acceptor (D–A) copolymer P3HT MEH-PPV homopolymers exhibit degrees short-range order, which can be associated with large differences...
Three cyclopentadithiophene-difluorophenylene copolymers (named PhF2,3, PhF2,5, and PhF2,6), which differ by the arrangement of fluorines on phenylene structural unit, were designed synthesized for fabrication organic field-effect transistors (OFETs). Single crystal structures model compounds representative backbone density functional theory (DFT) used to estimate shape each copolymer. The different substitution arrangements impact secondary structure through nonbonding F···H interactions....
Abstract Characterizing the density of states (DOS) width accurately is critical in understanding charge‐transport properties organic semiconducting materials as broader DOS distributions lead to an inferior transport. From a morphological standpoint, relative densities ordered and disordered regions are known affect films; however, comparison between molecular structures showing quantifiable at atomic level its impact on widths has yet be made. In this work, for first time, distribution two...
A new narrow bandgap non-fullerene electron acceptor was designed, synthesized, and characterized for near-infrared organic photovoltaics.
Conventional materials discovery is a laborious and time-consuming process that can take decades from initial conception of the material to commercialization. Recent developments in acceleration platforms promise accelerate using automation experiments coupled with machine learning. However, most efforts chemistry focus on synthesis compound identification, integrated target property characterization receiving less attention. In this work, an automated platform introduced for molecules as...
Self-driving laboratories (SDLs) promise an accelerated application of the scientific method. Through automation high-throughput experimentation, and autonomization experiment planning execution, SDLs hold potential to greatly accelerate research in chemistry materials discovery. This review article provides in-depth analysis state-of-the-art SDL technology, its applications across various disciplines, implications for research, industry. additionally overview enabling technologies SDLs,...
In this report, we investigate the binding properties of Lewis acid tris(pentafluorophenyl)borane with a base semiconducting polymer, PFPT, and subsequent mechanism band gap reduction. Experiments quantum chemical calculations confirm that formation adduct is energetically favorable (ΔG° < −0.2 eV), preferential at pyridyl nitrogen in polymer backbone over other sites. Upon formation, ultraviolet photoelectron spectroscopy indicates only slight decrease HOMO energy, implying larger reduction...
Contemporary materials discovery requires intricate sequences of synthesis, formulation and characterization that often span multiple locations with specialized expertise or instrumentation. To accelerate these workflows, we present a cloud-based strategy enables delocalized asynchronous design–make–test–analyze cycles. We showcase this approach through the exploration molecular gain for organic solid-state lasers as frontier application in optoelectronics. Distributed robotic synthesis...
Self-driving laboratories (SDLs) promise an accelerated application of the scientific method. Through automation experimental workflows, along with autonomization experiment planning, SDLs hold potential to greatly accelerate research in chemistry and materials discovery. This review article provides in-depth analysis state-of-the-art SDL technology, its applications across various disciplines, implications for research, industry. additionally overview enabling technologies SDLs, including...
High-performance organic semiconducting materials are reliant upon subtle changes in structure across different length scales. These morphological features control relevant physical properties and ultimately device performance. By combining situ NMR spectroscopy theoretical calculations, the conjugated small molecule TT is shown to exhibit distinct temperature-dependent local structural that related macroscopic properties. Specifically, lamellar melt states molecular topologies associated...
One of the biggest obstacles to successful polymer property prediction is an effective representation that accurately captures sequence repeat units in a polymer. Motivated by success data augmentation computer vision and natural language processing, we explore augmenting iteratively rearranging molecular while preserving correct connectivity, revealing additional substructural information not present single representation. We evaluate effects this technique on performance machine learning...