Supporting Information

Supporting Information Photoactive Surface-Grafted Polymer Brushes with Phthalocyanine Bridging Groups as an Advanced Architecture for Light Harvesting Michał Szuwarzyński,a,b Karol Wolski,b Agata Pomorska,b Tomasz Uchacz,b Arkadiusz Gut,b Łukasz Łapok,b Szczepan Zapotoczny*b a

AGH University of Science and Technology, Academic Centre for Materials and

Nanotechnology, al. Mickiewicza 30, 30-059, Krakow, Poland b

Jagiellonian University, Faculty of Chemistry, Ingardena 3, 30-060 Krakow, Poland

1. Experimental Part 1.1. Materials 1.2. Methods 1.3. Procedures 1.3.1. Syntheses and characterization of silicon phthalocyanines 1.3.2. Surface-initiated photoiniferter-mediated photopolymerization of TPM 1.3.3. “Click” reaction between azide-functionalized silicon phthalocyanine and deprotected poly(TPM) brushes followed in situ by QCM 1.3.4. Electrochemical characterization of azide-functionalized silicon phthalocyanine 1.3.5. Deposition of azide-functionalized silicon phthalocyanine (4) on poly(TPM) brushes 2. Results 2.1. Characterization of silicon phthalocyanine (3) 2.2. Characterization of azide-functionalized silicon phthalocyanine (4) 2.3. Electrochemical characterization of azide-functionalized silicon phthalocyanine (4) 2.4. Photophysical characterization of the silicon phtalocyanines 2.5. Thickness and surface roughness of poly(TPM) brushes 2.6. FTIR spectra of poly(TPM) brushes 2.7. Fluorescence decays of poly(TPM) brushes bridged with phthalocyanine chromophores 2.8. Fluorescence spectrum of azide-functionalized silicon phthalocyanine (4) deposited on poly(TPM) brushes 1

1. Experimental Part 1.1. Materials Quinoline (>98.0%, TCI Europe) was dried with NaOH and was freshly distilled under reduced pressure prior the application. Tetrabutylammonium tetrafluoroborate (≥ 99.0 % electrochemical grade) was purchased from Fluka. Toluene (p.a.), ethyl acetate (p.a.), n-hexane (p.a.), dichloromethane (p.a), sodium thiosulfate (p.a.) and sodium hydrogen carbonate (p.a.), potassium carbonate (p.a) were purchased from Chempur (Piekary Slaskie, Poland). Tetrahydrofuran (p.a), hydrogen

peroxide

and

sulfuric

acid

were

obtained

from

Merck.

p-

(chloromethyl)phenyltrimetoxysilane (CTPS, 95%) was purchased from ABCR (Karlsruhe, Germany). Methanol and ethanol (both p.a) were obtained from POCH (Gliwice, Poland). Copper (I) bromide (CuBr, 98%), N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDETA, 99%), ptolytrimethoxysilane, 1,3-diiminoisoindoline, diethylammonium diethyldithiocarbamate (97%), chloroform-d (99.8% atom D), triethylamine (≥99%), sodium azide (≥99%) were purchased from Sigma-Aldrich. Anhydrous magnesium sulfate (99.5%) was purchased from Alfa Aesar (Ward Hill, MA, USA). 3-trimethylsilyl-2-propynyl methacrylate (TPM) was synthesized based on the procedure described elsewhere.1 Quartz plates were obtained from Hellma Optik GmbH (Jena, Germany). Indium tin oxide (ITO) coated glass plates with the ITO layer thickness of 150 nm were obtained from VisionTek System LTD (Cheshire, United Kingdom).

1.2. Methods 1

H-NMR spectra were recorded on a Bruker 600 MHz while 13C-NMR spectra were recorded using

Bruker 151 MHz spectrometer. Deuterated dichloromethane was used for all the measurements. MALDI MS spectra were recorded in positive reflectron mode with the use of a MALDI-TOF/TOF mass spectrometer ultrafleXtreme (Bruker Daltonik). Cesium triiodide clusters were utilized for calibration of m/z scale. ESI mass spectra were recorded using Bruker Esquire 3000 ESI mass spectrometer equipped with an ion trap. UV-Vis absorption spectra were measured at room temperature using Varian Cary Eclipse spectrophotometer. The spectra were smoothened and baseline-corrected if necessary. For the elemental micro analysis the CHNS Vario Micro Cube analyzer combined with the electronic microbalance was used. Quartz Crystal Microbalance 2

(QCM) experiments were performed on the Stanford Research Systems model QCM200. 5 MHz quartz crystals (Inficon, Research Crystals) covered with Ti/Au/Ti/SiO2 layer were used for the measurements. FTIR spectra of the surface-grafted brushes on QCM crystals and ITO-coated glass substrates were recorded using Nicolet iS10 FT-IR spectrometer with grazing angle reflectance accessory (at 45°) using also p-polarized radiation. FTIR spectra of the modified phthalocyanines were recorded using the same spectrometer with ATR Smart iTX accessory with diamond crystal. Atomic Force Microscope (AFM) images were obtained with Dimension Icon AFM (Bruker, Santa Barbara, CA) working in the PeakForce Tapping (PFT) and QNM® modes in air using standard silicon cantilevers with nominal spring constant of 0.4 N/m (Bruker). Images in water were obtained using silicon cantilevers with normal spring constant of 0.7 N/m (Bruker). For determination of the brush thicknesses scratches in the polymer brush layers were generated using PTFE tweezers and the formed wells were imaged using AFM. The values measured in a few spots were averaged for a given sample (blank experiments on native substrates did not revealed formation of wells at the given conditions). Fluorescence steady-state and lifetime measurements were performed at room temperature using Fluorolog 3 spectrofluorometer (Horiba Jobin Yvon). The measurements were performed in air-equilibrated THF solutions using quartz cuvettes with a 1 cm optical path length. For solid samples (surface-grafted brushes) either 630 nm or 665 nm cutoff filter was used in the emission path in order to eliminate contribution of the scattered residual light from the excitation beam. The emission spectra were corrected for the instrumental response. The fluorescence quantum yield of SiPc was measured using zinc phthalocyanine in THF (Φfl=0.23)2 as a reference. The fluorescence decays for lifetime measurements were fitted using mono- or biexponential functions taking into account the contribution of the excitation pulse. Xenon lamp was used as a source of light for steady-state measurements while pulse diode emitting at 605 nm (pulse width