Tamar Segal-Peretz

Technion - Israel Institute of Technology | technion · Faculty of Chemical Engineering

Sequential infiltration synthesis (SIS), also known as vapor phase infiltration (VPI), is a quickly expanding technique that allows growth of inorganic materials within polymers from vapor phase precursors. With an increasing materials library, which encompasses numerous organometallic precursors and polymer chemistries, and an expanding applicatio...

Molecular layer deposition (MLD) provides the opportunity to perform condensation polymerization one vaporized monomer at a time for the creation of precise, selective nanofilms for desalination membranes. Here, we compare the structure, chemistry, and morphology of two types of commercial interfacial polymerzation (IP) membranes with lab-made MLD...

Today’s nanofabrication techniques require multistep and costly processes in order to fabricate complex, multi-materials nanostructures. Performing atomic layer deposition (ALD) within polymeric templates can offer a simple solution for nanostructure fabrication. In this process, named sequential infiltration synthesis (SIS), high partial pressures...

Inorganic‐organic mesophase materials provide a wide range of tunable properties, which are often highly dependent on their nano‐, micro‐, or meso‐scale compositions and structures. Among these are macroscopic orientational order and corresponding anisotropic material properties, the adjustability of which are difficult to achieve. This is due to t...

Block copolymers (BCPs) are considered model systems for understanding and utilizing self-assembly in soft matter. Their tunable nanometric structure and composition enable comprehensive studies of self-assembly processes as well as make them relevant materials in diverse applications. A key step in developing and controlling BCP nanostructures is...

Block copolymers (BCPs) are promising materials for water purification. They enable the fabrication of integral asymmetric isoporous membranes with high permeability and good selectivity. Commonly, the characterization of such hierarchical structures is performed by conventional electron microscopy (EM) means, namely scanning and transmission elect...

Sequential infiltration synthesis (SIS) has emerged in the past decade as a powerful technique for growth of inorganic materials within polymers through atomic layer deposition (ALD) chemistry. In SIS, ALD precursors diffuse into the polymer and interact with it, leading to inorganic materials growth within the polymer’s free volume. If desired, th...

Accomplishing on‐demand molecular separation with a high selectivity and good permeability is very desirable for pollutant removal and chemical and pharmaceutical processing. The major challenge for sub‐10 nm filtration of particles and molecules is the fabrication of high‐performance membranes with tunable pore size and designed functionality. Her...

The effect of confinement on electron and ion transport in oxide films is of interest both fundamentally and technologically for the design of next-generation electronic devices. In metal oxides with mobile ions and vacancies, it is the interplay of the different modes of charge transport and the corresponding current-voltage signatures that is of...

Nanoscale textured surfaces play an important role in creating antibacterial surfaces, broadband anti-reflective properties, and super-hydrophobicity in many technological systems. Creating nanoscale oxide textures on polymer substrates for applications such as ophthalmic lenses and flexible electronics imposes additional challenges over convention...

In recent years, atomic layer deposition (ALD) has emerged as a powerful technique for polymeric membrane surface modification. In this research, we study Al2O3 growth via ALD on two polymeric phase-inverted membranes: polyacrylonitrile (PAN) and polyetherimide (PEI). We demonstrate that Al2O3 can easily be grown on both membranes with as little as...

Hypothesis We show that one may employ polymer dewetting in solvent-non-solvent environment to obtain lithography-free fabrication of well-defined nano- to micro- scale polymer droplets array from pre-patterned polymer films. The polymer droplet pattern may be converted to a series of hybrid organic-inorganic and inorganic well-defined nano-pattern...

In this article, the limits of thin-film deposition on very rough topographies are demonstrated by depositing alumina on vertically aligned carbon nanotubes (VACNTs). Vapor deposition techniques are the enabling platforms of the thin-film industry, offering high material versatility and good coverage ability on relatively flat surfaces, leading to...

The ever increasing library of materials systems developed for organic solar‐cells, including highly promising non‐fullerene acceptors and new, high‐efficiency donor polymers, demands the development of methodologies that i) allow fast screening of a large number of donor:acceptor combinations prior to device fabrication and ii) permit rapid elucid...

Three-dimensional (3D) structures at the nanometer length scale play a crucial role in modern devices, but their fabrication using traditional top-down approaches is complex and expensive. Analogous to atomic lattices, block copolymers (BCPs) spontaneously form a rich variety of 3D nanostructures and have the potential to substantially simplify 3D...

Sequential infiltration synthesis (SIS) is an emerging method for vapor-phase growth of inorganic materials within polymers that is utilized for hybrid organic-inorganic and inorganic nanostructure fabrication. The range of SIS applications has been continuously expanding for the past decade. Fundamental understanding of precursor-polymer interacti...

In article number 1904657, Tamar Segal‐Peretz and co‐workers demonstrate a new approach in 3D nanostructures fabrication by developing spatially‐controlled growth of multiple metal oxides within polymer templates. The approach is utilized to fabricate metal oxide heterostructure nanorod arrays from self‐assembled block copolymer, showing the potent...

Nanofabrication is continuously searching for new methodologies to fabricate 3D nanostructures with 3D control over their chemical composition. A new approach for heterostructure nanorod array fabrication through spatially controlled–growth of multiple metal oxides within block copolymer (BCP) templates is presented. Selective growth of metal oxide...

The main focus of the present work is on identifying the critical parameters involved in inducing acid‐base cooperative catalytic interaction in hybrid metal‐polymer materials. To makes these hybrid materials Ti or Sn acid sites are grafted to the hydroxy groups of chitosan (CS). The cooperative catalytic interactions between the Ti/Sn and the prim...

Tin oxide (SnO2) nanostructures are attractive for sensing, catalysis, and optoelectronic applications. Here we investigate the fabrication of SnOx nanostructures through sequential infiltration synthesis (SIS) in block copolymer (BCP) film templates. While the growth of metal and metal oxides within polymers and BCP films via SIS has been demonstr...

A novel combination of block copolymer (BCP) nano spray‐drying (NSD), solvent annealing, and selective metal oxide growth is utilized to create functional polymer nanoparticles, polymer‐metal‐oxide hybrid nanoparticles, and templated metal oxide nanoparticles with tunable composition, internal morphology, and porosity. NSD of BCPs from chloroform a...

Hypothesis: Microstructural and rheological properties of particle-stabilized emulsions are highly influenced by the nanoparticle properties such as size and surface charge. Surface charge of colloidal particles not only influences the interfacial adsorption but also the interparticle network formed by the non-adsorbed particles in the continuous p...

Directed self-assembly (DSA) of block copolymers (BCPs) can achieve perfectly aligned structures at thermodynamic equilibrium, but the self-assembling morphology can become kinetically trapped in defective states. Understanding and optimizing the kinetic pathway toward domain alignment is crucial for enhancing process throughput and lowering defect...

There is considerable interest in developing multimodal characterization frameworks capable of probing critical properties of complex materials by relying on distinct, complementary methods or tools. Any such framework should maximize the amount of information that is extracted from any given experiment and should be sufficiently powerful and effic...

Control over nanopore size and 3D structure is necessary to advance membrane performance in ubiquitous separation devices. Here, inorganic nanoporous membranes are fabricated by combining the assembly of cylinder-forming poly(styrene-block-methyl methacrylate) (PS-b-PMMA) block copolymer and sequential infiltration synthesis (SIS). A key advance re...

Honeycomb Networks of Metal Oxides from Self-Assembling PS-PMMA Block Copolymers - Volume 23 Issue S1 - Frank Barrows, Paul Nealey, Tamar Segal-Peretz, Liliana Stan, Jeffrey Elam, Anil Mane, Ellie Porath, Charudatta Phatak, Amanda Petford-Long

Characterization of the three-dimensional (3D) structure in directed self-assembly (DSA) of block copolymers is crucial for understanding the complex relationships between the guiding template and the resulting polymer structure so DSA could be successfully implemented for advanced lithography applications. Here we combined scanning transmission el...

Full characterization of the three-dimensional structures resulting from the directed self-assembly (DSA) of block copolymers (BCP) remains a difficult challenge. Transmission electron microscope (TEM) tomography and resonant soft x-ray scattering have emerged as powerful and complementary methods for through-film characterization; both techniques...

Single ion conducting polymer electrolyte membranes (PEMs) are found at the heart of many electrochemical devices (e.g., fuel cells, flow batteries, electrolyzers, electrodialysis, etc.).( 1 ) The key requirements for such materials include high ionic conductivity, electron insulation, mechanical resilience, selectivity (i.e., high transference #),...

The three-dimensional assembly of poly (styrene-b-methyl methacrylate) (PS-b-PMMA) in chemoepitaxy and graphoepitaxy directed self-assembly (DSA) was investigated using scanning transmission electron microscopy (STEM) tomography. The tomographic characterization revealed hidden morphologies and defects at the BCP- chemical pattern interface in lame...

A review of the factors affecting directed self-assembly (DSA) of block copolymers on chemical nanopatterns is presented. The review starts with the formation of chemical patterns suitable for DSA, including patterns and processes that are compatible with industrial fabrication. The critical role of thermodynamics in DSA is then presented, includin...

Significance A molecular model is used to calculate the free energy of formation of ordered and disordered copolymer morphologies. We rely on advanced methodologies to identify the minimum free energy pathways that connect such states of the material. Our predictions for defect formation and annealing are compared with experimental observations. Ou...

Sequential infiltration synthesis (SIS) is a process derived from ALD in which a polymer is infused with inorganic material using sequential, self-limiting exposures to gaseous precursors. SIS can be used in lithography to harden polymer resists rendering them more robust towards subsequent etching, and this permits deeper and higher-resolution pat...

Block copolymers (BCP) are considered promising materials for advanced lithography in the sub-20 nm regime, as well as versatile building blocks for a variety of applications ranging from solar cells to membranes. Since the performance and functionally of BCP films is related to their three dimensional (3D) structure, it is desired to characterize...

Sequential infiltration synthesis (SIS) is a process derived from ALD in which a polymer is infused with inorganic material using sequential, self-limiting exposures to gaseous precursors. During the initial SIS cycles, the organometallic precursor (e.g. trimethyl aluminum, TMA) reacts preferentially with specific functional groups within the polym...

Understanding and controlling the three-dimensional structure of block copolymer (BCP) thin films is critical for utilizing these materials for sub-20 nm nanopatterning in semiconductor devices, as well as in membranes and solar cell applications. Combining an atomic layer deposition (ALD) based technique for enhancing the contrast of BCPs in trans...

Directed self-assembly (DSA) of block copolymers (BCPs) is a rising technique for sub-20 nm patterning. To fully harness DSA capabilities for patterning, a detailed understanding of the three dimensional (3D) structure of BCPs is needed. By combining sequential infiltration synthesis (SIS) and scanning transmission electron microscopy (STEM) tomogr...

The performances of hybrid organic–inorganic photovoltaics composed of conjugated polymers and metal oxides are generally limited by poor electronic coupling at hybrid interfaces. In this study, physicochemical interactions and bonding at the organic–inorganic interfaces are promoted by incorporating organoruthenium dye molecules into self-assemble...

Hybrid organic-inorganic bulk heterojunction (BHJ) photovoltaic devices continue to be a promising alternative for present semiconductor solar cell technology. However, to become competitive hybrid devices must improve their currently low efficien-cies. A major challenge to overcome is the control over the hybrid morphology, and more specifically,...

The organic-inorganic interfacial chemical composition and interaction have a critical influence on the performance of corresponding hybrid photovoltaic devices. Such interfaces have been shown to be controlled by using surfactants to promote contact between the highly hydrophobic electron-donating conjugated polymer species and hydrophilic electro...

The synthesis of mesostructured silica from a tetrahydrofuran (THF) based sol-gel was carried out in the channels of an anodic alumina membrane (AAM) using the evaporation induced self-assembly (EISA) method. The effect of channel surface chemistry on the orientation of the in-channel hexagonal mesostructure was studied by treating the channel wall...

Hybrid films of donor/acceptor conjugated polymer/metal oxides are considered promising materials for low-cost, solution-processed solar cells. Because device performances depend on the nanoscale film morphologies, most attention and extensive efforts have been invested in improving the nanofabrication of hybrid films. Nevertheless, the reported co...

The synthesis of mesostructured silica from a tetrahydrofuran (THF)-based sol gel was carried out in the channels of an anodic alumina membrane (AAM) using the evaporation-induced self-assembly (EISA) method. Two different nonionic surfactants were used as structure-directing agents, the triblock copolymer Pluronic P123 and the oligomer surfactant...

Correlating interfacial interactions and macroscopic photovoltaic properties of self-assembled hybrid materials Justin P. Jahnke1, Shany Neyshtadt2, Tamar Segal-Peretz2, Maria Diaz-Garcia3, Gitti L. Frey2, Brad F. Chmelka1* 1 Department of Chemical Engineering, University of California, Santa Barbara 2 Department of Materials Engineering, Tec...

Hybrid composites of semiconducting polymers and metal oxides are promising combinations for solar cells. However, forming a well-controlled nanostructure with bicontinuous interpenetrating networks throughout the photoactive film is difficult to achieve. Pre-structured “mesoporous” metal oxideelectrodes can act as a well-defined template for latte...

The chemical compositions and structures of organic-inorganic interfaces in mesostructurally ordered conjugated polymer-titania nanocomposites are shown to have a predominant influence on their photovoltaic properties. Such interfaces can be controlled by using surfactant structure-directing agents (SDAs) with different architectures and molecular...