Triazole-based ionene exhibiting tunable structure and ionic conductivity obtained via cycloaddition reaction: A new polyelectrolyte for electrochromic devices

Puguan, John Marc C.,Boton, Lilian B.,Kim, Hern Elsevier 2018 Solar energy materials and solar cells Vol.188 No.-

<P><B>Abstract</B></P> <P>Main-chain poly(ionic liquid)s based on 1,2,3-triazole with pentaoxyethylene spacer was developed via copper-catalyzed alkyne-azide cycloaddition (CuAAC) of a novel azide/alkyne-terminal monomer and subsequently quaternized by alkyl halides followed by anion exchanges with several fluorinated salts. Introduction of the extended ethylene oxide fragments [–(CH<SUB>2</SUB>CH<SUB>2</SUB>O)<SUB>5</SUB>–] has made this new PIL with methyl substituent and bis(trifluoromethane)sulfonimide counteranion exhibit ionic conductivity of 1.16 × 10<SUP>−4</SUP> S cm<SUP>−1</SUP> at 30 °C. This new electrolyte efficiently switches an electrochromic device (ECD) with 18% optical contrast from its transparent state to a colored state in 4.75 s and while bleaching takes 11.8 s. The development of this polyelectrolyte with simple structure and excellent physical and thermal properties is promising for the design of new all-solid state energy efficient smart windows and devices and other electrochemical device applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ionene with pentaoxyethylene spacer was synthesized via cycloaddition reaction. </LI> <LI> [–(CH<SUB>2</SUB>CH<SUB>2</SUB>O)<SUB>5</SUB>–] fragments on the main chain enhanced the PIL's ionic conductivity. </LI> <LI> Easy tunability of ionic conductivity and structure of ionenes. </LI> <LI> New series of PILs exhibit excellent thermal and mechanical properties. </LI> <LI> Fabricated ECD which efficiently switches from bleached to colored state. </LI> </UL> </P>

Ion-conductive and transparent PVdF-HFP/silane-functionalized ZrO₂ nanocomposite electrolyte for electrochromic applications

Puguan, John Marc C.,Chung, Wook-Jin,Kim, Hern Elsevier 2016 ELECTROCHIMICA ACTA Vol.196 No.-

<P><B>Abstract</B></P> <P>Polyvinylidene fluoride-co-hexafluoropropylene (PVdF-HFP) composite polymer electrolyte loaded with 3-isocyanatopropyltriethoxysilane (IPTES) functionalized zirconium oxide (ZrO<SUB>2</SUB>) nanoparticles is successfully synthesized and evaluated for electrochromic application. Incorporation of ZrO<SUB>2</SUB> into the polymeric substrate enhances the ionic conductivity of the electrolyte. Meanwhile, the functionalization of ZrO<SUB>2</SUB> nanoparticles with IPTES ligand enhances the electrolyte’s optical transmissivity. The amount of ligand and its time of reaction with ZrO<SUB>2</SUB> are found to affect the overall property of the electrolyte. The electrolyte exhibits a balance of low crystallinity and low ZrO<SUB>2</SUB> aggregation and agglomeration resulting to a potential next generation electrolyte for energy efficient windows.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Fast-switching all-solid state electrochromic device having main-chain 1,2,3-triazolium-based polyelectrolyte with extended oxyethylene spacer obtained via click chemistry

Puguan, John Marc C.,Jadhav, Amol R.,Boton, Lilian B.,Kim, Hern Elsevier 2018 Solar energy materials and solar cells Vol.179 No.-

<P><B>Abstract</B></P> <P>A fast-switching all-solid state symmetrical electrochromic device was successfully fabricated using poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) as electrode and a poly(ionic liquid) based on 1,2,3-triazole with oxyethylene spacer as solid electrolyte. PEDOT:PSS solution was spincoated on ITO glass and annealed to obtain the electrode layers. Two different types of electrolyte were synthesized via copper-catalyzed alkyne-azide cycloaddition (CuAAC) using novel azide/alkyne-terminal monomers. These newly developed main-chain 1,2,3-triazole-based poly(ionic liquid)s having variable spacer length underwent quaternization using methyl iodide and subsequently allowed to make anion exchange with lithium bis(trifluoromethane)sulfonimide salt to obtain PILs with remarkable properties. The PIL bearing [–(CH<SUB>2</SUB>CH<SUB>2</SUB>O)<SUB>6</SUB>–] spacer showed a conductivity of 1.20 × 10<SUP>−4</SUP> S cm<SUP>−1</SUP> which is at par with best side-chain PILs in literature and it efficiently switches an electrochromic device (ECD) with 22% optical contrast from its transparent state to a colored state in 2.5 s and 3.2 s to return to its bleached state. Likewise, it exhibits excellent thermal and mechanical stability that is ideal for practical applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> PILs with variable oxyethylene spacer were synthesized via click chemistry. </LI> <LI> Extended oxyethylene fragments significantly increased PIL’s ionic conductivity. </LI> <LI> Remarkably high ionic conductivity (σ = 1.20 × 10<SUP>−4</SUP> S cm<SUP>−1</SUP>) for main-chain PIL. </LI> <LI> All-solid state electrochromic device was successfully fabricated. </LI> <LI> Fast-switching ECD with ΔT = 22% and 2.5–3.2 s response time. </LI> </UL> </P>

Ionene copolymer electrolyte obtained from cyclo-addition of di-alkyne and di-azide monomers for solid-state smart glass windows

John Marc C. Puguan,김헌 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.74 No.-

A copoly(ionic liquid) (coPIL) based on 1,2,3-triazolium bearing trioxyethylene and tetraoxyethylenespacers was successfully synthesized as electrolyte for all-solid state electrochromic devices (ECD). Thispolyelectrolyte was produced by reacting triethylene glycol (TEG3)-diazide and tetraethylene glycol(TEG4)-dialkyne monomers through a ‘click’ reaction, copper-catalyzed alkyne-azidecycloadditon(CuAAC), and subsequently underwent several alkylation and anion metathesis. The new coPIL bearingethylene glycol fragments exhibited excellent thermal degradation temperature (Td10 = 230 C) and ionicconductivity (s = 8.8 10 5 S cm 1) which resulted to an efficient color switching (tc = 11.8 s andtb = 6.2 s), a high optical contrast (DT = 24%) and a remarkable stability (after 3000 cycles) of a symmetricall-solid-state smart glass window. The structural design of this new polyelectrolyte material and itscorresponding properties make it an excellent electrolyte for many electrochemical devices that requirezero electrolyte leakage.

Poly(vinyl alcohol) Membrane with Surface Immobilized β-Cyclodextrin Synthesis via Glutaraldehyde

Puguan, John Marc C.,Kim, Hern Trans Tech Publications 2012 Advanced materials research Vol.622 No.-

<P>A novel cyclodextrin (CD) grafted polyvinyl alcohol (PVA) material has been synthesized. Beta-cyclodextrin (βCD) is chemically grafted into PVA via glutaraldehyde (GA) in acidic medium (HCl). The reaction mechanism and the membrane surface grafting are confirmed by Fourier Transform Infrared Spectroscopy (FTIR), modulus of elasticity and contact angle determination. An amount of PVA and βCD are dissolved in a pH 3 HCl solution at 90oC with continuous stirring. Glutaraldehyde was slowly added into the clear solution to effect grafting and crosslinking between the PVA and βCD. It was cooled and allowed to stand overnight to eliminate bubbles formed. The clear PVA-GA-βCD material is casted on a glass plate to form membranes which are peeled off after subsequent drying. The grafted and crosslinked membrane showed peaks in the IR spectra confirming the chemical bonding between PVA, GA and βCD. PVA-GA-βCD membrane is 6% stronger than the physically blended membrane as shown by the increase of its modulus of elasticity. Likewise, a reduction in the hydrophilicity is observed by the newly synthesized membrane as shown by the increase of the membrane’s contact angle.This newly developed material with immobilized βCD may significantly improve the performance of PVA-CD pervaporation membranes by reducing the phase separation phenomenon due to agglomeration of CD in high concentrations as well as preventing βCD from dissolving in aqueous feed. Moreover, this may open new perspective for the development of high performance nanofibers and other nanomaterialssuch as drug delivery system materials and inclusion complexes.</P>

Tuning the structure and function of metal-organic framework (MOF) for dynamic control of solar light

( Pawan More ),( John Marc C. Puguan ),김헌 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Electrochromic material development aims to decrease power consumption while increasing the variety of desired colors. The deliberate insertion of redox-active naphthalenediimide (NDI) ligands into the versatile family of metal-organic frameworks known as MOF can be switched from transparent to dark. Zinc (Zn) metal center is integrated with the NDI and viologen moiety. While typical MOF has two reduction states, our viologen functionalized With NDI copolymer may give rise to multi reduction states, which means multiple colors can be observed. These MOF films were deposited on ITO substrate which exhibits cycling stability unrivaled by Organic linkers to significant optical contrast in a lithium-based electrolyte.

Optimized properties and electrochromic performance of WO3 based nanohybrids

( Deonikar Virendrakumar Gorakhnath ),( John Marc C Puguan ),김헌 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Electrochromic (EC) smart window is a new technology that is capable of changing from transparent to opaque and has the potential in energy saving applications. In this work, we have prepared a series of WO3 based hybrids by different synthesis method. In EC smart windows, WO3 is the key element where it is responsible for the colouring and bleaching of the device. Therefore, the properties of WO3 with different dopants will affect the EC performance. In this work, WO3 films were deposited on tin doped indium oxide (ITO) coated glasses. The WO3 film thicknesses were varied by means of number of deposited layers. Their morphological, structural, optical and EC properties were characterised by FE-SEM, XRD, UV-Vis. spectra, (CV) and (CA) measurements, respectively.

Fabrication of multifunctional wax infused porous PVDF film with switchable temperature response surface and anti corrosion property

Arni M. Pornea,John Marc C. Puguan,Virendrakumar G. Deonikar,Hern Kim 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.82 No.-

The discovery of the lubricant infused surface (LIS) embarked a promising approach on the active surfaceapplications. Demonstrated here is an intricately designed multifunctionalfilm influenced by bottom-upapproach, utilizing the underlying features of the compounding materials to provide greaterfunctionalities and opportunities for various applications. Through facile fabrication method, a porousfilm was generated by incorporating ZnO nanoparticle as a porogen onto PDVF polymer prior castingfollowed by simple acid washing for the removal of ZnO. Wax was used to lubricate the porous thinfilm;the design was inspired by the advantageous property of the wax that will enhance surface wettingproperties, exhibiting the surface with thermal responsiveness, anticorrosion protection and robuststructure. By taking advantage onto the lubricant’s rheological property, droplet motion control inresponse with the temperature variation was explored. Surface responses on different kinds of liquidswere also studied. The multifunctionalfilm manifested anticorrosion protection, which is supported byelectrochemical measurement technique. Thefilm’s stability was explored through exposure on harshcondition that successfully preserve its robust architecture.

Fabrication of ionic liquid/polymer nanoscale networks by electrospinning and chemical cross-linking and their application in hydrogen generation from the hydrolysis of NaBH₄

Chinnappan, Amutha,Jadhav, Arvind H.,Puguan, John Marc C.,Appiah-Ntiamoah, Richard,Kim, Hern Elsevier 2015 ENERGY Vol.79 No.-

<P><B>Abstract</B></P> <P>This study reports the development of a new system of IL (ionic liquid) with metal complex, chemically crosslinked, electrospun nanofibers based on PVDF (poly(vinylidene fluoride)) as a polymer matrix. The nanofibers were fabricated with different amounts of ionic liquid, PEG (polyethylene glycol), and EGDMA (ethylene glycol dimethacrylate) via electrospinning. The obtained nanofiber composites were thermal treated at 135 °C to produce physically bonded structures and chemically cross-linked networks, which were confirmed by SEM (Scanning Electron Microscopy), EDX (Energy Dispersive X-ray Spectrometer) and FT-IR spectra (Fourier transform infrared). The elecrospun PVDF/PEG/EGDMA/IL chemically cross-linked nanofibers were tested for the hydrogen generation from the hydrolysis of sodium borohydride. The nanofiber composites showed high stability and recycling ability in repeated number of runs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ionic liquid/polymer nanoscale networks were prepared by electrospinning method. </LI> <LI> The fabricated nanofibers cross-linked by thermal treatment. </LI> <LI> Crosslinked and non crosslinked nanofibers were investigated for hydrogen generation. </LI> <LI> Crosslinked nanofibers shown excellent performance. </LI> <LI> The stability and recyclability of the catalyst was excellent. </LI> </UL> </P>

Hydrogen generation from catalytic hydrolysis of sodium borohydride by a Cu and Mo promoted Co catalyst

Virendrakumar G. Deonikar,Pramod V. Rathod,Arni M. Pornea,John Marc C. Puguan,Kyoshik Park,Hern Kim 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.86 No.-

Catalytic hydrolysis of chemical hydrides with the use of NaBH4 is a safe and effective way to provide hydrogen fuel for new energy vehicles and portable electronic devices. Herein we developed a Cu and Mo promoted Co hierarchical composites (Co1−xCuxMoO4) for hydrolysis of NaBH4 via an easy synthesis route. FESEM analysis depicts that the morphology of Co1−xCuxMoO4 hierarchical composites varied significantly from irregular microsphere to marigold microsphere to rose like morphology with the increase in Cu (x) ratio with respect to Co (1 − x). Flower-like morphological architecture and crystal configuration empower the supported catalyst to exhibit a remarkable catalytic activity and outstanding catalytic activity was obtained for marigold-like Co0.9Cu0.1MoO4 catalyst with an H2 generation rate of 1005.7 mL min−1 g−1, which confirms existence of synergistic effect between Co, Cu and Mo. Lower loading of Cu in Co1−xCuxMoO4 supported the active sites of Co to increase its catalytic activity. Additionally, the catalyst exhibits good recyclability after five successive runs of hydrolytic reaction, making it a robust catalyst for hydrolysis of NaBH4 and could be considered as a potential catalyst for portable hydrogen fuel systems.