Supporting Information. Confinement of Semiconductor ZnO Nanoparticles in. Block-Copolymer Nanostructure

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1 Supporting Information Confinement of Semiconductor ZnO Nanoparticles in Block-Copolymer Nanostructure Anna Malafronte,, * Finizia Auriemma, Rocco Di Girolamo, Carmen Sasso, Claudia Diletto, A. Evelyn Di Mauro, Elisabetta Fanizza,, Pasquale Morvillo, Antonio M. Rodriguez, Ana B. Muñoz-Garcia, Michele Pavone, Claudio De Rosa. Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Monte S.Angelo, Via Cintia, I Napoli, Italy. Istituto per i processi Chimico Fisici, Consiglio Nazionale delle Ricerche, Via Orabona 4, I Bari, Italy. Dipartimento di Chimica, Università di Bari, Via Orabona 4, I-70126, Bari, Italy. ENEA Italian National Agency for New Technologies, Energy and Sustainable Development, SSPT-PROMAS-NANO Department, P.zza E. Fermi 1, I Portici, Napoli, Italy. S1

2 Scheme 1. Schematic representation of the fabricated electrical devices having a sandwich architecture ITO/polymer composite/al. Four different devices having 0.5 x 0.5 cm 2 active area (red squares) have been fabricated for each support (total area 2.5 x 2.5 cm 2 ) by using glass slides coated with two strips of ITO and shadow masks to evaporate aluminum top electrode. Figure S1. Kubelka-Munk function [F(R)hν] 2 versus photon energy (E) plot for drop casted film of ZnO colloidal solution before (A) and after (B) thermal annealing for 6 h at 150 C. A negligible increment in the energy gap (from 3.30 to 3.31 ev) is observed upon heating. S2

3 Figure S2. 1 H NMR spectrum of (HDA/TBPA)-capped ZnO NPs in the range ppm, where the signals used to quantify the relative amount of HDA and TBPA appear. The chemical formula of HDA and TBPA are also reported. The CH 3 protons of HDA (symbol *) appear at δ = 0.88 ppm, while the CH 2 protons of HDA (starting from, that is excluding the α-ch 2 proton), appear in the range δ = ppm. In this range (indicated with a bracket in the figure), also the CH 3 protons of TBPA appear (symbol ). The spectrum has been recorded in CDCl 3 on a Varian Inova 500 MHz spectrometer. Suspension of NPs in CDCl 3 (5 mg in 750 ml of solvent) has been sonicated for 30 minutes just before acquiring the NMR spectrum. Figure S3. EDX spectrum of ZnO nanoparticles after subtraction for the bremsstrahlung contribution in the background. S3

4 Table S1. Results of standardless quantitative analysis PB-ZAF obtained by FESEM-EDX measurements using the instrumental software QUANTAX ESPRIT 1.9. a Element Normalized Concentration wt% mol% Zinc 70 ± 4 39 ± 2 Oxygen 24 ± 6 55 ± 15 Phosphorus 5.5 ± ± 0.6 a) Atoms with atomic mass less than could not be detected. Table S2. Structural and electronic details from EA+TBPA adsorption on (1010) ZnO surface. The adsorption energy is given in ev. Distances (with standard deviation) and root mean square deviation (RMSD, from two upper ZnO atomic layers) are given in Å. EA & TBPA adsorption 1010 E ads (ev) d Zn-O (Å) (0.003) d Zn-NH2 (Å) d OH (Å) d P-OH (Å) (0.04) RMSD (Å) (a) (a) RMSD measures the average displacement of the ZnO two topmost atomic layers after adsorption of the capping molecules S4

5 A B Figure S4. Bright-field TEM images of a film of neat PS-b-PMMA (A) and of PS-b-PMMA/ZnO nanocomposite BCP-ZnO19 without performing any staining procedure. Both films have been annealed at 150 C in vacuum for 6 h. The contrast in B arises from the selective inclusion of ZnO NPs in the PS lamellar domains. A B Figure S5. Bright-field TEM images of thin films of the PS-b-PMMA/ZnO nanocomposite BCP- ZnO10 on ITO supports obtained without performing any thermal annealing, without staining (A) and stained with RuO 4 (B). S5

6 Computational details. Spin-polarized DFT calculations have been carried out with the PBE density functional including the last generation Grimme s correction for dispersion (D3BJ). We have used the PAW potentials from the VASP repository, purposely tailored to the PBE exchange correlation functional and all of standard hardness. The valence electrons used for each atom are: Zn, d 10 p 2 ; O, s 2 p 4 ; C, s 2 p 2 ; N, s 2 p 3 ; H, s 1 ; P, s 2 p 3. We have performed convergence test calculations of the total energy with respect to kinetic energy cut-off of the plane-wave basis set on the ZnO bulk. Convergence of total energy within 1mev/f.u. has been achieved with a cut-off of 750 ev. This cutoff value is much larger that the recommended one from VASP for all the listed atoms. Sampling of the Brillouin zone has been performed via automatic Γ-centered meshes: for the bulk structure we have used a 6x6x4 grid, while for the surface slabs we have used 6x4x1 and 4x4x1 grids for the cleaved the (1010) and (1120) surfaces, respectively. The total energies of the isolated molecules have been computed at the Γ-point after relaxation in a 10x10x10 Å 3 cubic unit-cell. Our (1010) surface slab model has three ZnO double layers along the z direction, and the (1120) surface slab model is based on five double layers along the z direction. In all the cases, only the two topmost layers exposed to the capping agents have been allowed to relax, while atoms of the bottom layers were fixed at their bulk positions. S6