Reliable unencapsulated Ag/Ag₂S micro-reference electrodes for battery research and other applications in organic media

N.Y.J. Tan ¹, Y. Wang ¹, S.W. Ang², Q.J. Seah ¹, M.M. Sun ¹, R.Q. Png ², P. K. H. Ho ², L.L. Chua ²¹,. Electrochem. Comms. 165 (2024) 107747 Abstract 

¹Department of Chemistry, NUS ²Department of Physics, NUS

Evidence for Morphology Control by Polyelectrolyte Templating in PEDT:PSSH

Q.M. Koh ¹, Q.J. Seah ¹, J.C. Yang ², M.N. Syafiqah ¹, Q.E. Hoh ¹, Z.L. Seah ², R.Q. Png ², P. K. H. Ho ², L.L. Chua ¹. Adv. Func. Mater. (2024) 2407493 Abstract 

¹Department of Chemistry, NUS ²Department of Physics, NUS

Optimization of fluorinated phenyl azides as universal photocrosslinkers for semiconducting polymers

Z.S. Tan ¹, Z. Jamal ¹, D.W.Y. Teo ¹, H.C. Ko ¹, Z.L Seah ², H.Y. Phua ², P. K. H. Ho ², R.Q. Png ², L.L. Chua ²¹,. Nat. Comms. 15 (2024) 6354 Abstract 

¹Department of Chemistry, NUS ²Department of Physics, NUS

Inverted device architecture for high efficiency single-layer organic light-emitting diodes with imbalanced charge transport

X. Tan ¹, D.H. Dou ¹, L.L. Chua ^2,3, R.Q. Png ², D.G. Congrave ⁴, H. Bronstein ^4,5, M. Baumgarten ¹, Y. Li ¹, P.W.M. Blom ¹, G-J. A.H. Wetzelaer ¹. Nat. Comms. 15 (2024) 4107 Abstract 

¹Max Planck Institute for Polymer Research, Mainz, Germany, ²Department of Physics, NUS, ³Department of Chemistry, NUS, ⁴Department of Chemistry, University of Cambridge, UK, ⁵Cavendish Laboratory, University of Cambridge, UK

Effects of Planarization of the Triphenylamine Unit on the Electronic and Transport Properties of Triarylamine-Fuorene Copolymers in Both Doped and Undoped Forms

Q.M. Koh ¹, M.N. Syafiqah ¹, Q.J. Seah ¹, J.C. Yang ², Y.J. Chen ¹, R.Q. Png ² ,P. K. H. Ho ², L.L. Chua ²¹,. ACS Appl. Mat. Interfaces. 16 (2024) 30 Abstract 

¹Department of Chemistry, NUS ²Department of Physics, NUS

Water binding and hygroscopicity in π-conjugated polyelectrolytes

C. G. Tang ¹, M.N. Syafiqah ², Q.M. Koh ², M. C.Y. Ang ², K.K. Choo ², M.M. Sun ², M. Callsen ¹, Y.P. Feng ¹, L.L. Chua ², R.Q. Png ¹, P. K. H. Ho ¹. Nat. Comms. 14 (2023) 3978 Abstract 

¹Department of Physics, NUS ²Department of Chemistry, NUS

Double-type-I charge-injection heterostructure for quantum-dot light-emitting diodes

L.X. Wang ^1,2, C. G. Tang ¹, Z. S. Tan ³, H. Y. Phua ¹, J. Chen ², L. Wei ²,R.Q. Png ¹, L.L. Chua ^1,3, P. K. H. Ho ¹. Mater. Horiz. 9 (2022) 2147-2159, Abstract 

¹Department of Physics, NUS ²Joint International Research Laboratory of Information Display and Visualization, School of Electronic Science and Engineering, Southeast University, Nanjing, People's Republic of China ³Department of Chemistry, NUS

Role of Linker Functionality in Polymers Exhibiting Main-Chain Thermally Activated Delayed Fluorescence

K. Philipps ¹, Yutaka Ie ², B. van der Zee ¹, R.Q. Png ²³, P. K. H. Ho ³, L.L. Chua ^3,4, E. del P. Rosendo ¹, C. Ramanan ¹, GJ. A. H. Wetzelaer ¹, P.W.M. Blom ¹, J. J. Michels ¹. Adv. Sci. (2022) 9, 220005 Abstract 

¹ Max Planck Institute for Polymer Research ²The Institute of Scientific and Industrial Research (ISIR), Osaka University, ³Department of Physics, NUS ⁴Department of Chemistry, NUS

Overcoming the water oxidative limit for ultra-high workfunction hole-doped polymers

Q.M. Koh ¹, C. G. Tang ², M. C.Y. Ang ¹, K.K. Choo ¹, Q.J. Seah ¹, R.Q. Png ², L.L. Chua ^1,2, P. K. H. Ho ². Nat. Comms. 12 (2021) 3345 Abstract 

¹Department of Chemistry, NUS ²Department of Physics, NUS,

Improving organic photovoltaic cells by forcing electrode work function well beyond onset of Ohmic transition

C. Zhao ¹, C. G. Tang ¹, Z.L. Seah ¹, Q.M. Koh ², L.L. Chua ^1,2, R.Q. Png ¹, P. K. H. Ho ². Nat. Comms. 12 (2021) 2250 Abstract 

¹Department of Physics, NUS, ²Department of Chemistry, NUS

Surface Doping of Organic Single-Crystal Semiconductors to Produce Strain-Sensitive Conductive Nanosheets

S. Watanabe ¹, R. Hakamatani ¹, K. Yaegashi ¹, Y. Yamashita ¹, H. Nozawa ¹, M. Sasaki ¹, S. Kumagai ¹, T. Okamoto ¹, C. G. Tang ², P. K. H. Ho ², L.L. Chua ^2,3, J. Takeya ¹. Adv. Sci. 8 (2021) 2002065 Abstract 

¹Material Innovation Research Center (MIRC) and Department ofAdvanced Materials Science, The University of Tokyo, ²Department of Physics, NUS, ³Department of Chemistry, NUS

Polymer-perovskite blend light-emitting diodes using a self-compensated heavily doped polymeric anode

A. G. Ricciardulli ¹, B. van der Zee ¹, K. Philipps ¹, G. A. H. Wetzelaer ¹, R.Q. Png ², P. K. H. Ho ², L.L. Chua ^2,3, Paul W. M. Blom ¹. APL Mater. 8 (2020) 021101 Abstract 

¹Max Planck Institute for Polymer Research, Germany, ²Department of Physics, NUS, ³Department of Chemistry, NUS

Role of Singlet and Triplet Excitons on the Electrical Stability of Polymer Light-Emitting Diodes

B. van der Zee ¹, S. Paulus ¹, R.Q. Png ², P. K. H. Ho ², L.L. Chua ^2,3, G. A. H. Wetzelaer ¹, P.W.M. Blom ¹. Adv. Electron. Mater. (2020), 6, 2000367 Abstract 

¹ Max Planck Institute for Polymer Research ²Department of Physics, NUS ³Department of Chemistry, NUS

General bis(fluorophenyl azide) photo-crosslinkers for conjugated and non-conjugated polyelectrolytes

D.W.Y. Teo ¹, J. Zaini ¹, Q.J. Seah ¹, R.Q. Png ², L.L. Chua ^1,2. J. Mater. Chem. C 8 (2020) 253 Abstract 

¹Department of Chemistry, NUS, ²Department of Physics, NUS

Bulk ion-clustering and surface ion-layering effects on work function of self-compensated charged-doped polymer semiconductors

M.C.Y. Ang ¹, C.G.Y. Tang ², Q.M. Koh ¹, C. Zhao ², Q.J. Seah ¹, Y. Wang ¹, M. Callsen ², Y.P. Feng ², R.Q. Png ², L.L. Chua ^1,2. Mater. Horiz., (2020) 7, 1073-1082 Abstract 

¹Department of Chemistry, NUS, ²Department of Physics, NUS

Spectator cation size effect on the work function and stability of self-compensated hole-doped polymers

M.C.Y. Ang ¹, Q.M. Koh ¹, C.G.Y. Tang ², Q.J. Seah ¹, Y. Wang ¹, M. Callsen ², Y.P. Feng ², R.Q. Png ², L.L. Chua ^1,2. J. Mater. Chem. C 8 (2020) 124 Abstract 

¹Department of Chemistry, NUS, ²Department of Physics, NUS

Multivalent anions as universal latent electron donors

C.G.Y. Tang ¹, M.N. Syafiqah ², Q.M. Koh ², C. Zhao ¹, J. Zaini ², Q.J. Seah ², M.J. Cass ³, M.J. Humphries ³, I. Grizzi ³, J.H. Burroughes ³, R.Q. Png ^1*, L.L. Chua ^1,2*, P.K.H. Ho ¹. Nature 573 (2019) 519 Abstract 

¹Department of Physics, NUS, ²Department of Chemistry, NUS, ³Cambridge Display Technology Ltd

Bias-induced electrochemical electron doping of organic semiconductor contacts

C. Zhao ¹, A.N. Utama ¹, K.K Choo ², L.L. Chua ², R.Q. Png ¹, P.K.H. Ho ¹. Adv. Mater. Interfaces (Early View) (2019) 1900607 Abstract PDF

¹Department of Physics, NUS, ²Department of Chemistry, NUS

Ohmic transition at contacts key to maximizing fill factor and performance of organic solar cells

J.K. Tan ^1,2, R.Q. Png ^1,2, C. Zhao ^1,2, P.K.H. Ho ^1,2. Nature Communications 9 (2018) 3269 Abstract PDF

¹Department of Physics, NUS, ²Solar Energy Research Institute of Singapore, NUS

Solution-processed 2-dimensional hole-doped ionic graphene compounds

F.Y. Kam ¹, R.Q. Png ², M.C.Y. Ang ¹, P. Kumar ², K Rubi ², R. Mahendiran ², O. Solomeshch ³, N. Tessler ³, G.K. Lim ^2,4, L.L. Chua ¹, P.K.H. Ho ². Materials Horizons 3 (2017) 456 Abstract

¹Department of Chemistry, NUS, ²Department of Physics, NUS, ³Department of Electrical Engineering, Technion, ⁴DSO National Laboratories, Singapore

Interface doping for ohmic organic semiconductor contacts using self-aligned polyelectrolyte counterion monolayer

W.L. Seah ¹, C.G.Y. Tang ¹, R.Q. Png ¹, V. Keerthi ², C. Zhao ¹, H. Guo ², J.G. Yang ¹, M. Zhou ³, P.K.H. Ho ¹, L.L. Chua ^1,2. Adv. Funct. Mater. 27 (2017) 18 Abstract

¹Department of Physics, NUS, ²Department of Chemistry, NUS, ³BASF South East Asia Pte Ltd

Doped polymer semiconductors with ultrahigh and ultralow work functions for ohmic contacts

C.G.Y. Tang ^1,2, M.C.Y. Ang ^2,3, K.K. Choo ³, V. Keerthi ³, J.K. Tan ^1,2, M.N. Syafiqah ³, T. Kugler ⁴, J.H. Burroughes ⁴, R.Q. Png ^1,2, L.L. Chua ^1,2,3, P.K.H. Ho ^1,2. Nature 539 (2016) 536 Abstract

¹Department of Physics, NUS, ²Solar Energy Research Institute of Singapore, NUS, ³Department of Chemistry, NUS, ⁴Cambridge Display Technology Ltd

Madelung and Hubbard interactions in polaron band model of doped organic semiconductors

R.Q. Png ^1,2, M.C.Y. Ang ^2,3, M.H. Teo ¹, K.K. Choo ³, C.G.Y. Tang ^1,2, D. Belaineh ¹, L.L. Chua ^1,2,3, P.K.H. Ho ^1,2. Nature Communications 7 (2016) 11948 Abstract PDF

¹Department of Physics, NUS, ²Solar Energy Research Institute of Singapore, NUS, ³Department of Chemistry, NUS

Characterization of ohmic contacts in polymer organic field-effect transistors

J.G. Yang ^1,3, W.L. Seah ¹, H. Guo ², J.K. Tan ¹, M. Zhou ⁵, R. Matsubara ⁴, M. Nakamura ⁴, R.Q. Png ¹, P.K.H. Ho ¹, L.L. Chua ^1,2. Org. Electron. 37 (2016) 491 Abstract

¹Department of Physics, NUS, ²Department of Chemistry, NUS, ³NUS Graduate School, NUS, ⁴Graduate School of Materials Science, NAIST, ⁵BASF South East Asia Pte Ltd

Perfluorinated ionomer-modified hole-injection layers: Ultrahigh-workfunction but nonohmic contacts

D. Belaineh ¹, J.K. Tan ¹, R.Q. Png ¹, P.F. Dee ¹, Y.M. Lee ¹, B.N.N. Thi ¹, N.S. Ridzuan ¹, P.K.H. Ho ¹. Adv. Funct. Mater. 25 (2015) 5504 Abstract

¹Department of Physics, NUS

Influence of Interfacial Area on Exciton Separation and Polaron Recombination in Nanostructured Bilayer All-Polymer Solar Cell

T.Pfadler ², M.Coric ², C.M. Palumbiny ³, A.C. Jakowetz ², K-P. Strunk ², J.A. Dorman ², P. Ehrenreich ², C. Wang ³, A. Hexemer ³, R.Q. Png ¹, P.K.H Ho ¹, P. Müller-Buschbaum ⁴, J. Weickert ², L. Schmidt-Mende ². ACS Nano. 8 (2014) 12397 Abstract

¹Department of Physics, NUS, ²Department of Physics, UKON, ³Lehrstuhl für Funktionelle Materialien, Physik Department E13, TUM, ⁴ Experimental Systems Advanced Light Source, Lawrence Berkeley National Lab

A High-performance p-doped conducting polymer blend based on sulfonated polyalkoxythiophene and poly(4-hydroxystyrene)

D. Belaineh ¹, R.Q. Png ¹, C.L. McGuiness ², M. Mathai ², V. Seshadri ², P.K.H. Ho ¹.Chem. Mater. 26 (2014) 4724 Abstract

¹Department of Physics, NUS, ²Solvay OLED, Plextronics

A transition solvent strategy to print polymer:fullerene films using halogen-free solvents for solar cell applications

G.H. Lim^1,3, J.M. Zhuo^1,2, L.Y. Wong¹, S.J. Chua³, L.L. Chua^1,2, P.K.H. Ho ^1,4. Org. Electron. 15 (2014) 449 Abstract

¹Department of Physics, NUS, ²Department of Chemistry, NUS, ³Department of Electrical and Computer Engineering, NUS, ⁴Solar Energy Research Institute of Singapore, NUS

Evalution of built-in potential and loss mechanisms at contacts in organic solar cells: device model parameterisation, validation, and prediction

B. Liu ¹, R.Q. Png ^1,2, J.K. Tan ^1,2, P.K.H. Ho ^1,2. Adv. Energy. Mater. 4 (2014) 1200972 Abstract

¹Department of Physics, NUS, ²Solar Energy Research Institute of Singapore, NUS

Efficient surfactant-free and chemical reductant-free solvothermal deoxidation of solution-processable sub-stoichiometric graphene oxide

Z.L. Chen¹, F.Y. Kam², V. Keerthi², J. Song², C. Hu², L.Y. Wong¹, G.K. Lim^1,3, L.L. Chua^1,2. J. Mater. Chem. C 1 (2013) 7246 Abstract

¹Department of Physics, NUS, ²Department of Chemistry, NUS, ³DSO National Laboratories, Singapore

Suppressing recombination in polymer photovoltaic devices via energy-level cascades

Z.K. Tan¹, K. Johnson¹, Y. Vaynzof¹, A.A. Bakulin², L.L. Chua³, P.K.H. Ho⁴, R.H. Friend¹ Adv. Mater. 25 (2013) 4131 Abstract

¹Cavendish Laboratory, University of Cambridge, ²FOM institute AMOLF, The Netherlands, ³Department of Chemistry, NUS, ⁴Department of Physics, NUS

Influence of graphite source on chemical oxidative reactivity

Z.L. Chen², F.Y. Kam¹, R.G.S. Goh², J. Song¹, G.K. Lim^2,3, L.L. Chua^1,2 Chemistry of Materials 25 (2013) 2944 Abstract

¹Department of Chemistry, NUS, ²Department of Physics, NUS, ³DSO National Laboratories, Singapore

A general method for transferring graphene onto soft surfaces

J. Song¹, F.Y. Kam¹, R.Q. Png², W.L. Seah², J.M. Zhuo², G.K. Lim ^2,3, P.K.H. Ho², L.L. Chua^1,2 Nature Nanotechnology 8 (2013) 356 Abstract

¹Department of Chemistry, NUS, ²Department of Physics, NUS, ³DSO National Laboratories, Singapore

Donor-acceptor interface modification by zwitterionic conjugated polyelectrolytes in polymer photovoltaics

A. Kumar¹, G. Pace¹, A.A. Bakulin¹, J.F. Fang², P.K.H. Ho³, W.T.S. Huck ², R.H. Friend¹, N.C. Greenham¹ Energy & Environmental Science 6 (2013) 1589 Abstract

¹Cavendish Laboratory, University of Cambridge, ²Melville Laboratory for Polymer Synthesis, University of Cambridge, ³Department of Physics, NUS

Jettable fluid space and jetting characteristics of a microprint head

L.Y. Wong¹, G.H. Lim^1,2, T. Ye¹, F.B.S. Silva¹, J.M. Zhuo¹, R.Q. Png¹, S.J. Chua², P.K.H. Ho¹ Journal of Fluid Mechanics 713 (2012) 109 Abstract

¹Department of Physics, NUS, ²Department of Electrical and Computer Engineering, NUS

High internal quantum efficiency in fullerene solar cells based on crosslinked polymer donor networks

B. Liu¹, R.Q. Png¹, L.H. Zhao², L.L. Chua^1,2, R.H. Friend^1,3, P.K.H. Ho^1,4 Nature Communications 3 (2012) 1321 Abstract PDF

¹Department of Physics, NUS, ²Department of Chemistry, NUS, ³Cavendish Laboratory, University of Cambridge, ⁴Solar Energy Research Institute of Singapore, NUS

Furan substituted diketopyrrolopyrrole and thienylenevinylene based low band gap copolymer for high mobility organic thin film transistors

P. Sonar¹, J.M. Zhuo², L.H. Zhao³, K.M. Lim², J.H. Chen⁴, A.J. Rondinone⁴, S.P. Singh^1,5, L.L. Chua^2,3, P.K.H. Ho², A. Dodabalapur^1,6 Journal of Materials Chemistry 22 (2012) 17284 Abstract

¹Institute of Materials Research and Engineering (IMRE), A*STAR, ²Department of Physics, NUS, ³Department of Chemistry, NUS, ⁴Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, ⁵School of Natural Sciences, Shiv Nadar University, ⁶Microelectronics Research Centre, The University of Texas at Austin

Polarization effects on energy-level alignment at the interfaces of polymer organic semiconductor films

L.H. Zhao^1,2, R.Q. Png¹, C.C.H. Chiam¹, H. Guo¹, J.M. Zhuo¹, L.L. Chua^1,2, A.T.S. Wee¹, P.K.H. Ho¹ Applied Physics Letters 101 (2012) 053304 Abstract

¹Department of Physics, NUS, ²Department of Chemistry, NUS

Effective work functions for the evaporated metal/organic semiconductor contacts from in-situ diode flatband potential measurements

M. Zhou¹, R.Q. Png¹, S.H. Khong², S. Sivaramakrishnan¹, L.H. Zhao³, L.L. Chua^1,2,3, R.H. Friend^1,2, P.K.H. Ho¹ Applied Physics Letters 101 (2012) 013501 Abstract

¹Department of Physics, NUS, ²Cavendish Laboratory, University of Cambridge, ³Department of Chemistry, NUS

Role of borderline solvents to induce pronounced extended-chain lamellar order in π-stackable polymers

L.H. Zhao¹, R.Q. Png¹, J.M. Zhuo², L.Y. Wong¹, J.C. Tang², Y.S. Su¹, L.L. Chua^1,2 Macromolecules 44 (2011) 9692 Abstract

¹Department of Physics, NUS, ²Department of Chemistry, NUS

Giant broadband nonlinear optical absorption response in dispersed graphene single sheets

G.K. Lim^1,2, Z.L. Chen², J. Clark⁴, R.G.S. Goh³, W.H. Ng¹, H.W. Tan¹, R.H. Friend^2,4, P.H.K. Ho², L.L. Chua^2,3,4 Nature Photonics 5 (2011) 554 Abstract

¹DSO National Laboratories, Singapore and ²Department of Physics, NUS, ³Department of Chemistry, NUS, ⁴Cavendish Laboratory, University of Cambridge

Surface-directed spinodal decomposition in poly[3-hexylthiophene] and C61-Butyric acid methyl ester blends

Y. Vaynzof¹, D. Kabra¹, L.H. Zhao², L.L. Chua², U. Steiner¹, R.H. Friend^1,2ACS Nano 5 (2011) 329 Abstract

¹Cavendish Laboratory, University of Cambridge and ²Department of Physics, NUS

Improved electron injection in poly(9,9'-dioctylfluorene)- co-benzothiodiazole via cesium carbonate by means of coannealing

Y. Vaynzof¹, D. Kabra¹,L.L. Chua², R.H. Friend^1,2Applied Physics Letters 98 (2011) 113306 Abstract

¹Cavendish Laboratory, University of Cambridge and ²Department of Physics, NUS

The dependence of device dark current on the active-layer morphology of solution-processed organic photodetectors

P. E. Keivanidis^1,2, P.K.H. Ho³, R. H. Friend^2,3, N. C. Greenham² Advanced Functional Materials 20 (2010) 3895 Abstract

¹Departments of Physics, Imperial College, ²Cavendish Laboratory, University of Cambridge and ³Department of Physics, NUS

Determination of the interface δ-hole density in a blue-emitting organic semiconductor diode by electromodulated absorption spectroscopy

M. Zhou¹, R.Q. Png¹, S. Sivaramakrishnan¹, P.J. Chia¹, C.K. Yong¹, L.L. Chua^1,2, P. K. H. Ho¹ Applied Physics Letters 97 (2010)113505 Abstract

¹Departments of Physics, and ²Chemistry, NUS.

Printable metal nanoparticle inks

B. T. Anto¹, L.Y. Wong¹, R.Q. Png¹, S. Sivaramakrishnan¹, L.L. Chua^1,2, P. K. H. Ho¹ Handbook of Nanophysics, Functional Nanomaterials. Chapter 2. ISBN: 978-1-4200-7552-6 Summary of book

¹Departments of Physics, and ²Chemistry, NUS.

Interplay of processing, morphological order, and charge-carrier mobility in polythiophene thin films deposited by different methods: comparison of spin-Cast, drop-Cast, and inkjet-printed films

L.Y. Wong¹,R.Q. Png¹, F.B. Shanjeera Silva¹, L.L. Chua^1,2, D. V. Maheswar Repaka¹, S. Chen^1,3, X. Y. Gao^1,3, L. Ke⁴, S. J. Chua⁴, A.T.S. Wee^1,3, P. K. H. Ho¹ Langmuir 26 (2010) 15494 Abstract

¹Departments of Physics, and ²Chemistry, ³Singapore Synchrotron Light Source, NUS ⁴ Institute of Materials Research & Engineering, A*STAR.

Hydrophilic sparse ionic monolayer-protected metal nanoparticles: highly concentrated nano-Au and nano-Ag ‘‘inks’’ that can be sintered to near-bulk conductivity at 150°C

B.T. Anto¹, S. Sivaramakrishnan¹, L.L. Chua^1,2, P.K.H. Ho² Advanced Functional Materials 20 (2010) 296 Abstract

¹Departments of Physics, and ²Chemistry, NUS.

Improved photoinduced charge carriers separation in organic-inorganic hybrid photovoltaic devices

Y. Vaynzof¹, D. Kabra¹, L.H. Zhao², P.K.H. Ho², A.T.S. Wee², R.H. Friend^1,2 Applied Physics Letters 97 (2010) 033309 Abstract

¹Cavendish Laboratory, University of Cambridge. ²Department of Physics, NUS.

High-performance polymer semiconducting heterostructure devices by nitrene-mediated photocrosslinking of alkyl side chains

R.Q. Png¹, P.J. Chia¹, J.C. Tang², B. Liu¹, S. Sivaramakrishnan¹, M. Zhou¹, S-H. Khong³, H. S. O. Chan², J. H. Burroughes^4, L.L. Chua^1,2,3, R.H. Friend^1,3, P.K.H. Ho¹ Nature Materials 9 (2010) 152 Abstract

¹Departments of Physics, and ²Chemistry, NUS. ³Cavendish Laboratory, University of Cambridge. ⁴Cambridge Display Technology Ltd.

Solution-processed conjugated polymer organic p-i-n light-emitting diodes with high built-in potential by solution- and solid-state doping

S. Sivaramakrishnan¹, M. Zhou¹, A. C. Kumar¹, Z. Chen¹, R.Q. Png¹, L.L. Chua^2,3, P.K.H. Ho¹. Applied Physics Letters 95 (2009) 213303 Abstract

¹Departments of Physics, and ²Chemistry, NUS. ³Cavendish Laboratory, University of Cambridge.

Direct spectroscopic evidence for a photodoping mechanism in polythiophene and poly(bithiophene-alt-thienothiophene) organic semiconductor thin films involving oxygen and sorbed moisture

J.M. Zhuo², L.H. Zhao¹, R.Q. Png¹, L.Y. Wong¹, P.J. Chia¹, J.C. Tang², S. Sivaramakrishnan¹, M. Zhou¹, E.C.W. Ow¹, S.J. Chua³, W.S. Sim², L.L. Chua^1,2, P.K.H. Ho¹. Advanced Materials 21 (2009) 4747 Abstract

¹Departments of Physics, and ²Chemistry, NUS. ³Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research).

Role of delta-hole-doped interfaces at ohmic contacts to organic semiconductor

M. Zhou¹, L.L. Chua^1,2, R.Q. Png¹, C.K. Yong¹, S. Sivaramakrishnan¹, P.J. Chia¹, A.T.S. Wee¹, R.H. Friend^1,3, P.K.H. Ho¹. Physical Review Letters 103 (2009) 036601 Abstract

¹Departments of Physics, and ²Chemistry, NUS. ³Cavendish Laboratory, University of Cambridge.

All-solution based device engineering of multilayer polymeric photodiodes: Minimizing dark current

P.E. Keivanidis¹, S-H. Khong¹, P.K.H. Ho², N.C. Greenham¹, R.H. Friend^1,2 Applied Physics Letters 94 (2009) 173303 Abstract

¹Cavendish Laboratory, University of Cambridge. ²Department of Physics, NUS.

Direct evidence for the role of the madelung potential in determining the work function of doped organic semiconductors

P.J. Chia¹, S. Sivaramakrishnan¹,M. Zhou¹, R.Q. Png¹, L.L. Chua^1,2, R.H. Friend^1,3, P.K.H. Ho¹Physical Review Letters 102 (2009)096602 Abstract

¹Departments of Physics, and ²Chemistry, NUS.³Cavendish Laboratory, University of Cambridge.

Direct evidence for delocalization of charge carriers at the Fermi level in a doped conducting polymer

J.M. Zhuo^1,2, LH. Zhao², P.J. Chia², W.S. Sim¹, R.H. Friend^2,3, P.K.H. Ho² Physical Review Letters 100 (2008) 186601 Abstract

¹Departments of Physics, and ²Chemistry, NUS. ³Cavendish Laboratory, University of Cambridge.

Polyfluorene-based light-emitting diodes with an azide photocross-linked poly(3,4-ethylene dioxythiophene):(polystyrene sulfonic acid) hole-injecting layer

G. Winroth², G. Latini², D. Gredgington², L.Y. Wong¹, L.L. Chua¹, P.K.H. Ho¹, F. Cacialli² Applied Physics Letters 92 (2008) 103308 Abstract

¹Department of Physics, NUS. ²Department of Physics and Astronomy and London Centre for Nanotechnology, University College London.

Robust reproducible large-area molecular rectifier junctions

H.J. Che^1,2, P.J. Chia¹, L.L. Chua¹, S. Sivaramakrishnan¹, J.C. Tang², A.T.S. Wee¹, H.S.O. Chan², P.K.H. Ho¹ Applied Physics Letters 92 (2008) 253503 Abstract

¹Departments of Physics, and ²Chemistry, NUS.

Chemical reversability of the electrical dedoping of conducting polymers: An organic chemically erasable programmable read-only memory

P.J. Chia^1,2, Y.C. Yeo², J.H. Burroughes³, R.H. Friend^1,4, P.K.H. Ho Applied Physics Letters 93 (2008) 033314 Abstract

¹Departments of Physics, and ²Electrical and Computer Engineering, NUS. ³Cambridge Display Technology Ltd. ⁴Cavendish Laboratory, Department of Physics, University of Cambridge.

Band-like transport in surface-functionalized highly solution-processable graphene nanosheets

S.Wang¹, P.J. Chia¹, L.L. Chua¹, L.H. Zhao¹, R.Q. Png¹, S. Sivaramakrishnan¹, M. Zhou¹, R.G.S. Goh¹, R.H. Friend^1,2, A.T.S. Wee¹, P.K.H. Ho¹ Advanced Materials 20 (2008) 3440 Abstract

¹Department of Physics, NUS. ²Cavendish Laboratory, University of Cambridge.

Deoxidation of graphene oxide nanosheets to extended graphenites by “unzipping” elimination

L.L. Chua^1,2, S. Wang¹, P.J. Chia¹, L. Chen¹, L.H. Zhao¹, W. Chen¹, A.T.S. Wee¹ and P.K.H. Ho¹ The Journal of Chemical Physics 129 (2008)114702 Abstract

¹Departments of Physics, and ²Chemistry, NUS.

Solvent effects and multiple aggregate states in high-mobility organic field-effect transistors based on poly(bithiophene-alt-thienothiophene)

S. Wang¹, J.C. Tang², L.H. Zhao¹, R.Q. Png¹, L. Y. Wong¹, P.J. Chia¹, H.S.O. Chan², P.K.H. Ho¹, L.L.Chua^1,2 Applied Physics Letters 93 (2008) 162103 Abstract

¹Departments of Physics, and ²Chemistry, NUS.

Impact of self-assembled monolayer on low frequency noise of organic thin film transistors

K. Lin¹, S. L. Dolmanan¹, L. Shen¹, C. Vijila¹, S.J. Chua¹, R.Q. Png², P.J. Chia², L.L.Chua², P.K.H. Ho² Applied Physics Letters 93 (2008) 153507 Abstract

¹Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research). ²Department of Physics, NUS.

Controlled insulator-to-metal transformation in printable polymer composites with nanometal clusters

S. Sivaramakrishnan¹, P.J. Chia^1,2, Y. C. Yeo², L.L. Chua¹ and P.K.H. Ho¹ Nature Materials 6 (2007) 149 Abstract

¹Departments of Physics, and ²Electrical and Computer Engineering, NUS.

Solvent effects on chain orientation and interchain pi -interaction in conjugated polymer thin films: direct measurements of the air and substrate interfaces by near-edge X-ray absorption spectroscopy

P.K.H. Ho¹, L.L. Chua^1,2, M. Dipankar¹, X. Gao¹, D. Qi¹, A.T.S. Wee¹, J. F. Chang² and R.H. Friend² Advanced Materials 19 (2007) 215 Abstract

¹Department of Physics, NUS. ²Cavendish Laboratory, University of Cambridge.

Electromigration of the conducting polymer in organic semiconductor devices and its stabilization by cross-linking

R.Q. Png^1,2, P.J. Chia^1,3, S. Sivaramakrishnan¹, L.Y. Wong¹, M. Zhou¹, L.L. Chua¹ and P.K.H. Ho¹ Applied Physics Letters 91 (2007) 013511 Abstract

¹Departments of Physics, and ²Materials Science, ³Electrical and Computer Engineering, NUS.

General photo-patterning of polyelectrolyte thin films via efficient ionic bis(fluorinated phenyl azide) photo-crosslinkers and their post-deposition modification

S.H. Khong, S. Sivaramakrishnan, R.Q. Png, L.Y. Wong, P.J. Chia, L.L. Chua and P.K.H. Ho Advanced Functional Materials 17 (2007) 2490 Abstract

Department of Physics, NUS.

Injection-induced de-doping in a conducting polymer during device operation: Asymmetry in the hole injection and extraction rates

P.J. Chia^1,3, L.L. Chua¹, S.Sivaramakrishnan¹, J.M. Zhuo^1,2, L.H. Zhao¹, W.S. Sim², Y.C. Yeo³, P.K.H. Ho¹ Advanced Materials 19 (2007) 4202 Abstract

¹Departments of Physics, ²Chemistry, and ³Electrical and Computer Engineering, NUS.

Large damage threshold and small electron escape depth in X-ray absorption spectroscopy of a conjugated polymer thin film

L.L. Chua, M. Dipankar, S. Sivaramakrishnan, X. Gao, D. Qi, A.T.S. Wee and P.K.H. Ho Langmuir 22 (2006) 8587 Abstract

Department of Physics, NUS.

General observation of n-type field-effect behaviour in organic semiconductors

L.L. Chua^1,2, J. Zaumseil¹, J.F. Chang¹, E.C.W. Ou³, P.K.H. Ho¹, H. Sirringhaus¹, R.H. Friend¹ Nature 434 (2005) 194 Abstract

¹Cavendish Laboratory, Department of Physics, University of Cambridge. ²Department of Physics, NUS. ³Institute of Materials Research and Engineering, A*STAR

Organic double-gate field-effect transistors: Logic-AND operation

L.L. Chua^1,2, R.H. Friend¹ and P.K.H. Ho² Applied Physics Letters 87 (2005) 253512 Abstract

¹Cavendish Laboratory, Department of Physics, University of Cambridge. ²Department of Physics, NUS