concurrent-quantitative-conductivity-mechanical-properties

Concurrent Quantitative Conductivity and Mechanical Properties Measurements of Organic Photovoltaic Materials using AFM

Organic photovoltaic  (OPV) materials are inherently inhomogeneous at the nanometer scale. Nanoscale  inhomogeneity of OPV materials affects performance ...

procedure-for-transfer-polymer-films-onto-porous-substrates-with

Procedure for the Transfer of Polymer Films Onto Porous Substrates with Minimized Defects

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support ...

Conjugated polymers represent a promising class of organic semiconductors with potential applications in a variety of molecular devices. Poly(3-alkylthiophene)s, in particular, are garnering interest due to their large charge carrier mobility and band gap in the visible region of the spectrum. Defects play a pivotal role in determining the performance of polymer electronics, and yet the function of specific types of defects is still largely unknown. Density functional theory calculations of alkyl-substituted oligothiophenes are used to isolate the effect of static inter-ring torsion defects on key parameters such as electronic coupling between rings and band gap. Results have potential implications both for the fundamental understanding of intramolecular charge transport and for improving processing in organic devices.

Isolating the effect of torsional defects on mobility and band gap in conjugated polymers.

Konjugierte Polymere sind eine vielversprechende Klasse organischer Halbleiter mit m&ouml;glichen Anwendungen in einer Vielzahl von molekularen Ger&auml;ten. Poly (3-Alkylthiophene) s, insbesondere Verankerung sind Interesse durch ihre gro&szlig;en Ladung-F&ouml;rdermaschine Mobilit&auml;t und Band der L&uuml;cke im sichtbaren Bereich des Spektrums. Defekte spielen eine entscheidende Rolle bei der Bestimmung der Leistung der Polymerelektronik, und noch die Funktion bestimmter Arten von M&auml;ngeln ist noch weitgehend unbekannt. Dichte funktionalen Theorie Berechnungen der Alkyl-substituierte Oligothiophenes werden verwendet, um die Wirkung der ruhende inter-ring Torsion M&auml;ngel auf wichtige Parameter wie elektronische Kopplung zwischen Ringen und Bandabstand zu isolieren. Ergebnisse haben m&ouml;gliche Implikationen f&uuml;r das grundlegende Verst&auml;ndnis der intramolekulare kostenlos Transport und Verarbeitung in organischen Bauelementen zu verbessern.

Die Wirkung der Torsionssteifigkeit M&auml;ngel auf Mobilit&auml;t und Bandabstand in konjugierten Polymeren zu isolieren.

Geometric defects in conjugated polymers play a critical role in determining electronic structure and properties such as charge carrier mobility and band gap. Because the relative roles of individual defects are experimentally difficult to discern, computational approaches provide valuable insight if appropriate molecular models are used. Poly(3-alkylthiophenes) are often modeled with very short backbones and without their side chains. We demonstrate the shortcomings of this approach for modeling torsional disorder in poly(3-hexylthiophene) (P3HT). Using a hybrid density functional model, we identify a minimal acceptable model to comprise approximately 10 monomers with explicitly treated alkane side chains. Potential applications of this work extend to polymer electronics and optoelectronics.

Importance of side chains and backbone length in defect modeling of poly(3-alkylthiophenes).

Geometrische M&auml;ngel in konjugierten Polymeren spielen eine entscheidende Rolle bei der Bestimmung der elektronischen Struktur und Eigenschaften wie Ladung-F&ouml;rdermaschine-Mobilit&auml;t und Bandabstand. Da die relativen Rollen der einzelnen M&auml;ngel experimentell schwer zu erkennen sind, bieten computational Ans&auml;tzen wertvolle Einblicke, wenn entsprechende Molekulare Modelle verwendet werden. Poly(3-alkylthiophenes) werden h&auml;ufig modelliert, mit sehr kurzen Backbones und ohne ihre Seitenketten. Wir zeigen die M&auml;ngel dieses Ansatzes zur Modellierung von Torsions-Unordnung im poly(3-hexylthiophene) (P3HT). Verwenden ein Hybrid-Dichte-Funktionsmodell, identifizieren wir minimal akzeptabel Modell um etwa 10 Monomere mit explizit behandelten Alkan-Seitenketten umfassen. Anwendungsm&ouml;glichkeiten dieser Arbeit erstrecken sich auf Polymerelektronik und Optoelektronik.

Bedeutung der Seitenketten und R&uuml;ckgrat L&auml;nge in defekt Modellierung von poly(3-alkylthiophenes).

One approach for making inexpensive inorganic-organic hybrid photovoltaic (PV) cells is to fill highly ordered TiO(2) nanotube (NT) arrays with solid organic hole conductors such as conjugated polymers. Here, a new in situ UV polymerization method for growing polythiophene (UV-PT) inside TiO(2) NTs is presented and compared to the conventional approach of infiltrating NTs with pre-synthesized polymer. A nanotubular TiO(2) substrate is immersed in a 2,5-diiodothiophene (DIT) monomer precursor solution and then irradiated with UV light. The selective UV photodissociation of the C--I bond produces monomer radicals with intact pi-ring structure that further produce longer oligothiophene/PT molecules. Complete photoluminescence quenching upon UV irradiation suggests coupling between radicals created from DIT and at the TiO(2) surface via a charge transfer complex. Coupling with the TiO(2) surface improves UV-PT crystallinity and pi-pi stacking; flat photocurrent values show that charge recombination during hole transport through the polymer is negligible. A non-ideal, backside-illuminated setup under illumination of 620-nm light yields a photocurrent density of approximately 5 microA cm(2)-surprisingly much stronger than with comparable devices fabricated with polymer synthesized ex situ. Since in this backside architecture setup we illuminate the cell through the Ag top electrode, there is a possibility for Ag plasmon-enhanced solar energy conversion. By using this simple in situ UV polymerization method that couples the conjugated polymer to the TiO(2) surface, the absorption of sunlight can be improved and the charge carrier mobility of the photoactive layer can be enhanced.

Improved hybrid solar cells via in situ UV polymerization.

Ein Ansatz zur Herstellung von preiswerten anorganisch-Organische Photovoltaik (PV) Hybridzellen ist hochgradig geordnete TiO(2) Nanotube (NT) Arrays mit festen organischen Loch Dirigenten wie Konjugierte Polymere zu f&uuml;llen. Hier ist eine neue in-situ UV-Polymerisation-Methode f&uuml;r den Anbau von Polythiophen (UV-PT) innen TiO(2) NTs vorgestellt und im Vergleich zu den herk&ouml;mmlichen Ansatz des NTs mit pre-synthesized Polymer Infiltration. Ein Nanotubular TiO(2) Substrat ist in einer 2,5-Diiodothiophene (DIT)-Monomer-Vorl&auml;ufer-L&ouml;sung getaucht und dann mit UV-Licht bestrahlt. Die selektive UV-Photolyse des C--bond ich produziert Monomer Wurzeln mit intakten Pi-Ringstruktur, die l&auml;nger Oligothiophen/PT-Molek&uuml;le weiter zu produzieren. Komplette Photolumineszenz abschrecken auf UV-Bestrahlung deutet Kopplung zwischen radikalen erstellt von DIT und an der TiO(2)-Oberfl&auml;che &uuml;ber eine kostenlos-&Uuml;bertragung komplexer. Kopplung mit der TiO(2)-Oberfl&auml;che verbessert UV-PT Kristallinit&auml;t und Stapeln von Pi-Pi; flache Photostrommessungen Werte zeigen, dass die Rekombination w&auml;hrend Loch Transport durch das Polymer zu berechnen ist vernachl&auml;ssigbar. Eine nicht idealen, R&uuml;ckseite beleuchteten Setup unter Beleuchtung von 620 nm Licht ergibt eine Photostrommessungen Dichte von etwa 5 MicroA cm 2-&uuml;berraschend viel st&auml;rker als mit vergleichbaren Ger&auml;ten mit Polymer synthetisiert ex-Situ hergestellt. Da bei diesem Hintern Architektur Setup wir die Zelle durch die oberen Ag-Elektrode beleuchten, besteht die M&ouml;glichkeit f&uuml;r Ag-Plasmon-verst&auml;rkte solar Energie-Umwandlung. Mithilfe dieser einfachen in-situ UV-Polymerisation-Methode, die Paare von konjugierten Polymers an die TiO(2)-Oberfl&auml;che, die Absorption von Sonnenlicht verbessert werden kann und die kostenlos Tr&auml;ger Mobilit&auml;t der fotoaktiven Ebene verbessert werden kann.

Verbesserte Hybrid-Solarzellen &uuml;ber in-situ UV-Polymerisation.

Thin films of poly(3-hexylthiophene)-block-polylactide block copolymer exhibiting ordered lamellar morphology have been selectively etched to produce structured films that could be used in fabrication of idealized bulk heterojunctions for organic or hybrid solar energy devices. Etched poly(3-hexylthiophene) films, after being rinsed in water to remove degraded polylactide fragments, were dried using various drying approaches that reduce or alleviate surface tension forces generated during liquid evaporation from the film. As emphasized by atomic force microscopy, X-ray diffraction, and emission photoluminescence, a reduction in domain collapse leads to improved molecular ordering in the plane perpendicular to the substrate and enhanced photoluminescence quenching when paired with fullerene C(60) hydroxide electron acceptors.

Minimizing lateral domain collapse in etched poly(3-hexylthiophene)-block-polylactide thin films for improved optoelectronic performance.

D&uuml;nnschichten der poly(3-hexylthiophene)-Block-Polylactid Block Copolymer ausstellenden lamell&auml;re Morphologie bestellt haben wurde selektiv ge&auml;tzt, um strukturierte Filme zu produzieren, die Herstellung von idealisierten Massen ALFOEROWS f&uuml;r verwendet werden k&ouml;nnte organische oder Hybrid-solar-Energie-Ger&auml;te. Ge&auml;tzte poly(3-hexylthiophene) Filme, wurden nach in Wasser degradierten Polylactid Fragmente, entfernen Sie gesp&uuml;lt wird getrocknet und mit verschiedenen trocknenden Ans&auml;tze, die zu reduzieren oder zu lindern Oberfl&auml;chenspannung Kr&auml;fte w&auml;hrend fl&uuml;ssige Verdampfung aus dem Film erzeugt. Wie durch Rasterkraftmikroskopie, R&ouml;ntgenstrahlbeugung und Emission Photolumineszenz betont, eine Verringerung der Dom&auml;ne f&uuml;hrt verbesserte Molekulare Anordnung in der Ebene senkrecht zum Untergrund und verbesserte Photolumineszenz abschrecken, wenn gepaart mit Fulleren C(60) hydroxid Elektronenakzeptoren zusammenbrechen.

Minimierung seitliche Dom&auml;ne Zusammenbruch im ge&auml;tzten poly(3-hexylthiophene)-Block-Polylactid-D&uuml;nnschichten f&uuml;r verbesserte optoelektronische Leistung.

Nanoscopic patterned materials with tunable dimensions via atomic layer deposition on block copolymers.

Nanoskopische gemusterte Materialien mit einstellbare Dimensionen &uuml;ber atomic Layer Deposition von Block-Copolymeren.

A series of semiconducting copolymers (PTAT-x) containing extended Ï€-conjugated tetrathienoanthracene units have been synthesized. It was shown that the extended conjugation system enhanced the Ï€-Ï€ stacking in the polymer/PC(61)BM blend films and facilitated the charge transport in heterojunction solar cell devices. After structural fine-tuning, the polymer with bulky 2-butyloctyl side chains (PTAT-3) exhibited a PCE of 5.6% when it was blended with PC(61)BM.

Tetrathienoanthracene-based copolymers for efficient solar cells.

Eine Reihe von halbleitenden Copolymere (PTAT-X), enth&auml;lt erweiterte &pi;-konjugierten Tetrathienoanthracene, die Einheiten synthetisiert wurde, haben. Es wurde gezeigt, dass das erweiterte Konjugation-System die &pi;-&pi; Stapeln in den Polymer/PC (61) BM Mischung Filmen und erleichtert den Transport kostenlos in Heterojunction Solarzelle Ger&auml;ten verbessert. Nach strukturellen Feinabstimmung ausgestellt das Polymer mit sperrigen 2-Butyloctyl-Seitenketten (PTAT-3) ein PCE von 5,6 %, wenn es mit PC (61) BM gemischt wurde.

Tetrathienoanthracene-basierte Copolymere f&uuml;r effiziente Solarzellen.

Sequential infiltration synthesis (SIS), combining stepwise molecular assembly reactions with self-assembled block copolymer (BCP) substrates, provides a new strategy to pattern nanoscopic materials in a controllable way. The selective reaction of a metal precursor with one of the pristine BCP domains is the key step in the SIS process. Here we present a straightforward strategy to selectively modify self-assembled polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) BCP thin films to enable the SIS of a variety of materials including SiO(2), ZnO, and W. The selective and controlled interaction of trimethyl aluminum with carbonyl groups in the PMMA polymer domains generates Al-CH(3)/Al-OH sites inside the BCP scaffold which can seed the subsequent growth of a diverse range of materials without requiring complex block copolymer design and synthesis.

A route to nanoscopic materials via sequential infiltration synthesis on block copolymer templates.

Sequenzielle Eindringen Synthese (SIS), kombiniert schrittweisen molekularen Versammlung Reaktionen mit monomolekularen Block Copolymer (BCP) Substrate, bietet eine neue Strategie, um Muster nanoskopische Materialien in einer kontrollierbaren Weise. Die selektive Reaktion Metall Vorl&auml;ufer mit einer unber&uuml;hrten BCP-Domains ist der wichtigste Schritt in der SIS-Prozess. Hier pr&auml;sentieren wir Ihnen eine einfache Strategie, um selektiv monomolekularen Polystyrol-Block-Poly(methylmethacrylat) (PS-b-PMMA) BCP D&uuml;nnschichten SIS von einer Vielzahl von Materialien, einschlie&szlig;lich SiO(2), ZnO und W. aktivieren &auml;ndern Die gezielte und kontrollierte Interaktion Trimethyl-Aluminium mit Carbonyl-Gruppen in den PMMA-Polymer-Dom&auml;nen erzeugt Al-CH 3/Al-OH Site innerhalb der BCP-Ger&uuml;st, das das nachfolgende Wachstum der unterschiedlichsten Materialien seed k&ouml;nnen, ohne dass komplexe Block-Copolymer-Design und Synthese.

Eine Route zu nanoskopische Materialien &uuml;ber sequentielle Eindringen Synthese auf Block-Copolymer-Vorlagen.

PTB7 semiconducting copolymer comprising thieno[3,4-b]thiophene and benzodithiophene alternating repeat units set a historic record of solar energy conversion efficiency (7.4%) in polymer/fullerene bulk heterojunction solar cells. To further improve solar cell performance, a thorough understanding of structure-property relationships associated with PTB7/fullerene and related organic photovoltaic (OPV) devices is crucial. Traditionally, OPV active layers are viewed as an interpenetrating network of pure polymers and fullerenes with discrete interfaces. Here we show that the active layer of PTB7/fullerene OPV devices in fact involves hierarchical nanomorphologies ranging from several nanometers of crystallites to tens of nanometers of nanocrystallite aggregates in PTB7-rich and fullerene-rich domains, themselves hundreds of nanometers in size. These hierarchical nanomorphologies are coupled to significantly enhanced exciton dissociation, which consequently contribute to photocurrent, indicating that the nanostructural characteristics at multiple length scales is one of the key factors determining the performance of PTB7 copolymer, and likely most polymer/fullerene systems, in OPV devices.

Hierarchical nanomorphologies promote exciton dissociation in polymer/fullerene bulk heterojunction solar cells.

PTB7 halbleitenden Copolymer bestehend aus Thieno [3, 4-b] Thiophen und Benzodithiophene abwechselnd wiederholen Einheiten legen einen historischen Rekord von Solarenergie Umwandlungseffizienz (7,4 %) im Polymer/Fulleren Bulk Heterojunction Solarzellen. Zur weiteren Verbesserung der Solarzelle Leistung ein gr&uuml;ndliches Verst&auml;ndnis der Struktur-Eigenschaftsbeziehungen mit PTB7/Fulleren und &auml;hnliche organische Photovoltaik (OPV) Ger&auml;ten ist von entscheidender Bedeutung. Traditionell werden OPV aktive Schichten als durchdringende Netzwerk von reinen Polymere und Fullerene mit diskreten Schnittstellen angesehen. Hier zeigen wir, dass die aktive Schicht der PTB7/Fulleren OPV-Ger&auml;te tats&auml;chlich hierarchische Nanomorphologies zig Nanometer Nanocrystallite Aggregate in PTB7-Reich und Fulleren-Reich-Dom&auml;nen sich Hunderte von Nanometer in der Gr&ouml;&szlig;e von einigen Nanometern der Kristallite bis beinhaltet. Diese hierarchische Nanomorphologies sind zu erheblich verbesserten Exziton Dissoziation, die folglich dazu, Photostrommessungen beitragen, darauf hinweist, dass die Nanostructural Merkmale auf mehrere L&auml;nge Skalen ist einer der Schl&uuml;sselfaktoren, die Ermittlung der Leistung PTB7 Copolymer und wahrscheinlich die meisten Polymer/Fulleren-Systeme, von OPV-Ger&auml;te gekoppelt.

Hierarchische Nanomorphologies f&ouml;rdern Exziton Dissoziation in Polymer/Fulleren Bulk Heterojunction Solarzellen.

Enhanced lithographic imaging layer meets semiconductor manufacturing specification a decade early.

Erweiterte lithographischen bildgebende Schicht trifft Halbleiter-Fertigung-Spezifikation eine Dekade fr&uuml;h.

Three new tailor-made molecules (DPDCTB, DPDCPB, and DTDCPB) were strategically designed and convergently synthesized as donor materials for small-molecule organic solar cells. These compounds possess a donor-acceptor-acceptor molecular architecture, in which various electron-donating moieties are connected to an electron-withdrawing dicyanovinylene moiety through another electron-accepting 2,1,3-benzothiadiazole block. The molecular structures and crystal packings of DTDCPB and the previously reported DTDCTB were characterized by single-crystal X-ray crystallography. Photophysical and electrochemical properties as well as energy levels of this series of donor molecules were thoroughly investigated, affording clear structure-property relationships. By delicate manipulation of the trade-off between the photovoltage and the photocurrent via molecular structure engineering together with device optimizations, which included fine-tuning the layer thicknesses and the donor:acceptor blended ratio in the bulk heterojunction layer, vacuum-deposited hybrid planar-mixed heterojunction devices utilizing DTDCPB as the donor and C(70) as the acceptor showed the best performance with a power conversion efficiency (PCE) of 6.6 Â± 0.2% (the highest PCE of 6.8%), along with an open-circuit voltage (V(oc)) of 0.93 Â± 0.02 V, a short-circuit current density (J(sc)) of 13.48 Â± 0.27 mA/cm(2), and a fill factor (FF) of 0.53 Â± 0.02, under 1 sun (100 mW/cm(2)) AM 1.5G simulated solar illumination.

Vacuum-deposited small-molecule organic solar cells with high power conversion efficiencies by judicious molecular design and device optimization.

Drei neue ma&szlig;geschneiderte Molek&uuml;le (DPDCTB, DPDCPB und DTDCPB) wurden strategisch geplant und um als Spender Materialien f&uuml;r organische Solarzellen klein-Molek&uuml;l synthetisiert. Diese Verbindungen besitzen eine Donor-Akzeptor-Akzeptor molekulare Architektur, in der verschiedene Elektron-Spende Adsorptionseigenschaften mit einer Aberkennung der Elektron Dicyanovinylene Teil durch ein anderes Elektron-akzeptieren 2,1,3-Benzothiadiazole-Block verbunden sind. Die molekularen Strukturen und Kristall Umschlie&szlig;ungen mit DTDCPB und die zuvor gemeldeten DTDCTB waren gekennzeichnet durch Einzel-Kristall Kristallstrukturanalyse. Photophysikalische sowie elektrochemische Eigenschaften und Energieniveaus dieser Serie Spender Molek&uuml;le wurden gr&uuml;ndlich untersucht, mit klarer Struktur-Eigenschaftsbeziehungen. Mit zarten Manipulation der den Kompromiss zwischen der Photovoltaik und der Photostrommessungen &uuml;ber molekulare Struktur Technik zusammen mit Ger&auml;t Optimierungen enthalten, die Feinabstimmung der Schichtdicken und das Spender: Akzeptor-gemischt-Verh&auml;ltnis in der Bulk Heterojunction Schicht, Vakuum-hinterlegt Hybrid planar gemischt Heterojunction Ger&auml;te nutzt DTDCPB als Spender und C(70), wie der Akzeptor die beste Leistung mit einer Effizienz (PCE) von 6,6 &plusmn; 0,2 % (die h&ouml;chste PCE von 6,8 %) zeigte, zusammen mit einer Leerlaufspannung (V(oc)) von 0,93 &plusmn; 0,02 V, ein Kurzschluss Stromdichte (J(sc)) von 13,48 &plusmn; 0.27 mA/cm(2) und F&uuml;llfaktor (FF) 0,53 &plusmn; 0,02, unter 1 sun (100 mW/cm(2)) AM 1,5 G simuliert solar Beleuchtung.

Vakuum-hinterlegt klein-Molek&uuml;l organische Solarzellen mit high-Power-Conversion-Effizienz durch vern&uuml;nftige Molekulare Optimierung f&uuml;r Design und Ger&auml;t.

Konjugierte Polymere, die auf der Grundlage einer Heteroacene, 3,7-dialkyl-dithieno[2,3-d:2&#39;,3&#39;-d&#39;]benzo[1,2-b:4,5-b&#39;]dithiophene (DBD), synthetisiert. Diese Polymere zeigen Breite UV-Vis-Aufnahme mit Energie Bandgaps unter 1,7 eV. PTDBD2, gute Mischbarkeit in ein Polymer/Phenyl-C71-Butters&auml;ure Acid Methylester (PC(71) BM) zeigen Film mischen, bleibt eine (PCE) die Effizienz von 7,6 %. Die Ergebnisse zeigen, dass Copolymere mit DBD vielversprechende Kandidaten f&uuml;r Hochleistungs-organische Solarzellen.

Synthese und photovoltaischer Effekt in Dithieno[2,3-d:2&#39;,3&#39;-d&#39;]Benzo[1,2-b:4,5-b&#39;]dithiophene-Based Konjugierte Polymere.

Conjugated polymers based on a heteroacene, 3,7-dialkyl-dithieno[2,3-d:2',3'-d']benzo[1,2-b:4,5-b']dithiophene (DBD), are synthesized. These polymers show broad UV-vis absorption with energy bandgaps below 1.7 eV. PTDBD2, showing good miscibility in a polymer/phenyl-C71-butyric acid methyl ester (PC(71) BM) blend film, achieves a power conversion efficiency (PCE) of 7.6%. The results indicate that copolymers containing DBD are promising candidates for high-performance organic solar cells.

Synthesis and Photovoltaic Effect in Dithieno[2,3-d:2',3'-d']Benzo[1,2-b:4,5-b']dithiophene-Based Conjugated Polymers.

Organic photovoltaics (OPVs) are a promising carbon-neutral energy conversion technology, with recent improvements pushing power conversion efficiencies over 10%. A major factor limiting OPV performance is inefficiency of charge transport in organic semiconducting materials (OSCs). Due to strong coupling with lattice degrees of freedom, the charges form polarons, localized quasi-particles comprised of charges dressed with phonons. These polarons can be conceptualized as pseudo-atoms with a greater effective mass than a bare charge. We propose that due to this increased mass, polarons can be modeled with Langevin molecular dynamics (LMD), a classical approach with a computational cost much lower than most quantum mechanical methods. Here we present LMD simulations of charge transfer between a pair of fullerene molecules, which commonly serve as electron acceptors in OSCs. We find transfer rates consistent with experimental measurements of charge mobility, suggesting that this method may provide quantitative predictions of efficiency when used to simulate materials on the device scale. Our approach also offers information that is not captured in the overall transfer rate or mobility: in the simulation data, we observe exactly when and why intermolecular transfer events occur. In addition, we demonstrate that these simulations can shed light on the properties of polarons in OSCs. Much remains to be learned about these quasi-particles, and there are no widely accepted methods for calculating properties such as effective mass and friction. Our model offers a promising approach to exploring mass and friction as well as providing insight into the details of polaron transport in OSCs.

Molecular dynamics and charge transport in organic semiconductors: a classical approach to modeling electron transfer.

There are broad interests in selective and localized synthesis in nanodomains of self-assembled block copolymers (BCPs) for a variety of applications. Sequential infiltration synthesis (SIS) shows promise to selectively grow a controllable amount of materials in one type of nanodomain of a self-assembled BCP film. However, the effects of nanostructured domains in a BCP film and SIS cycles on the material growth behavior of SIS are rarely studied. In this work, we investigated the growth behavior of TiO SIS within self-assembled polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) films and the two corresponding pure homopolymer films (PS and PMMA) by using in situ quartz crystal microbalance (QCM). According to the experimental results, reactant purge steps are essential to enable a high selectivity of SIS in PMMA nanodomains in the BCP films by eliminating the undesired homogeneous reactions. The continuous PS nanodomain acts as the main channel in transporting reactants to PMMA nanodomains in the self-assembled PS-b-PMMA BCP films. The segregated nanoscale PMMA nanodomains in the BCP films show dramatically different TiCl diffusion/reaction behavior than a continuous PMMA film. The mass gain per SIS cycle within PMMA nanodomains decreases quickly with increasing cycle number. After 7 TiO SIS cycles, TiO SIS can only take place at the interface between PS and PMMA nanodomains in the BCP film. The TiO SIS process can uniformly modify PMMA nanodomains throughout a self-assembled PS-b-PMMA film up to the diffusion depth owing to the unique nanostructure-enabled diffusion. SIS cycle number and chemistry of a BCP will strongly affect the material growth behavior of a SIS chemistry on the BCP film and, therefore, the final morphology of the resulting nanomaterial. Detailed studies are warranted for a SIS process on a self-assembled BCP film of different chemistry.

Effect of Nanostructured Domains in Self-Assembled Block Copolymer Films on Sequential Infiltration Synthesis.

Crude oil fouling on membrane surfaces is a persistent, crippling challenge in oil spill remediation and oilfield wastewater treatment. In this research, we present how a nanosized oxide coating can profoundly affect the anti-crude-oil property of membrane materials. Select oxide coatings with a thickness of ∼10 nm are deposited conformally on common polymer membrane surfaces by atomic layer deposition to significantly mitigate fouling during filtration processes. TiO- and SnO-coated membranes exhibited far greater anti-crude-oil performance than ZnO- and AlO-coated ones. Tightly bound hydration layers play a crucial role in protecting the surface from crude oil adhesion, as revealed by molecular dynamics simulations. This work provides a facile strategy to fabricate crude-oil-resistant membranes with negligible impact on membrane structure, and also demonstrates that, contrary to common belief, excellent crude oil resistance can be achieved easily without implementation of sophisticated, hierarchical structures.

Crude-Oil-Repellent Membranes by Atomic Layer Deposition: Oxide Interface Engineering.

In many applications, interfaces govern the performance of membranes. Structure, chemistry, electrostatics, and other properties of interfaces can dominate the selectivity, flux, fouling resistance, and other critical aspects of membrane functionality. Control over membrane interfacial properties, therefore, is a powerful means of tailoring performance. In this Minireview, we discuss the application of atomic layer deposition (ALD) and related techniques in the design of novel membrane interfaces. We discuss recent literature in which ALD is used to (1) modify the surface chemistry and interfacial properties of membranes, (2) tailor the pore sizes and separation characteristics of membranes, and (3) enable novel advanced functional membranes.

ArticleTotal : 2	Year
Publication title Cited by 3	2013
Publication title Cited by 4	2019

Article	Year
Isolating the effect of torsional defects on mobility and band gap in conjugated polymers. The journal of physical chemistry. B\| PubMed ID: 18597518	2008
Importance of side chains and backbone length in defect modeling of poly(3-alkylthiophenes). The journal of physical chemistry. B\| PubMed ID: 19290596	2009
Improved hybrid solar cells via in situ UV polymerization. Small (Weinheim an der Bergstrasse, Germany)\| PubMed ID: 19367599	2009
Minimizing lateral domain collapse in etched poly(3-hexylthiophene)-block-polylactide thin films for improved optoelectronic performance. Langmuir : the ACS journal of surfaces and colloids\| PubMed ID: 20146485	2010
Nanoscopic patterned materials with tunable dimensions via atomic layer deposition on block copolymers. Advanced materials (Deerfield Beach, Fla.)\| PubMed ID: 20827673	2010
Tetrathienoanthracene-based copolymers for efficient solar cells. Journal of the American Chemical Society\| PubMed ID: 21332135	2011
A route to nanoscopic materials via sequential infiltration synthesis on block copolymer templates. ACS nano\| PubMed ID: 21545142	2011
Hierarchical nanomorphologies promote exciton dissociation in polymer/fullerene bulk heterojunction solar cells. Nano letters\| PubMed ID: 21823620	2011
Enhanced lithographic imaging layer meets semiconductor manufacturing specification a decade early. Advanced materials (Deerfield Beach, Fla.)\| PubMed ID: 22488639	2012
Vacuum-deposited small-molecule organic solar cells with high power conversion efficiencies by judicious molecular design and device optimization. Journal of the American Chemical Society\| PubMed ID: 22831172	2012
Synthesis and Photovoltaic Effect in Dithieno[2,3-d:2',3'-d']Benzo[1,2-b:4,5-b']dithiophene-Based Conjugated Polymers. Advanced materials (Deerfield Beach, Fla.)\| PubMed ID: 23161802	2012
Molecular dynamics and charge transport in organic semiconductors: a classical approach to modeling electron transfer. Chemical science\| PubMed ID: 28553494	2017
Effect of Nanostructured Domains in Self-Assembled Block Copolymer Films on Sequential Infiltration Synthesis. Langmuir : the ACS journal of surfaces and colloids\| PubMed ID: 29039679	2017
Crude-Oil-Repellent Membranes by Atomic Layer Deposition: Oxide Interface Engineering. ACS nano\| PubMed ID: 30107114	2018
Atomic layer deposition for membrane interface engineering. Nanoscale\| PubMed ID: 30397691	2018

Seth B. Darling

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