## 4 Experimental
### Materials and Devices Characterisations  
The crystalline structures of SANP-S and SANP-T were examined using X-ray diffractometer (MMA, GBC Scientific Equipment LLC, Hampshire, IL, USA) (40 kV, 30 mA, Cu K\(\alpha\) radiation, \(\lambda\) = 1.5406 A) in the range of 20 = 20-80\({}^{\circ}\), with a scan rate of 1\({}^{\circ}\)/min. The morphologies were examined by field emission scanning electron microscopy, FE-SEM (JEOL JSM 7500 FA, Japan). A Tristar-3020 nitrogen adsorption-desorption equipment (Micrometrics, USA) was used to obtain the specific surface area and pore volume values. A Dektak 150 Surface Profiler (Veeco, USA) was used to determine the film thicknesses. The amounts of N719 and D149 dyes on the different films were calculated by measuring the absorbance of dyes desorbed from the films (thickness = 5 \(\upmu\)m, area = 1 cm\({}^{2}\)) in 4 mL of a 0.1 M NaOH (Sigma, USA) solution (distilled water/ethanol 1:1 v/v) for N719 or in 4 mL of 0.4 M NaOH in methanol (Chem Supply, Australia) for D149 [15; 35], using a Shimadzu UV-3600 spectrophotometer (Japan). Diffuse reflectance measurements were conducted using an integratingsphere attachment (ISR-3100) (Japan) and the above spectrophotometer. A Horiba Jobin Yvon HR800 confocal Raman (Japan) with a 632.8 nm laser was used to measure the Raman shift of films (also 3 \(\upmu\)m). The Raman spectra were recorded in the wavenumber range between 100 and 800 cm\({}^{-1}\). Photocurrent density-voltage (J-V) measurements were measured using a solar simulator with an AM1.5 filter set to 1 sun (100 mW/cm\({}^{2}\), PV Measurements, Colorado, USA.). A QEX10 system from (PV Measurements, USA) was used for the incident to photocurrent conversion efficiency (IPCE) measurements in 5 nm steps. A Reference 600 Potentiostat (GAMRY Instrument, USA) was used for electrochemical impedance spectroscopy measurements (EIS) which were carried out for DSCs based on different photoanodes under 1 sun illumination with \(V_{oc}\) in a frequency range of 0.1-10\({}^{6}\) Hz and AC voltage of 10 mV.  
The following are available online at [[http://www.mdpi.com/2076-3417/9/5/979/s1](http://www.mdpi.com/2076-3417/9/5/979/s1)]([http://www.mdpi.com/2076-3417/9/5/979/s1](http://www.mdpi.com/2076-3417/9/5/979/s1)), Figure S1: Low magnification SEM images of (a) SANP-S; (b) SANP-T; and (c) photographs of undyed films demonstrating the difference in scattering properties, Figure S2: The transmittances of undyed SANP-S and undyed SANP-T photoanode films with an average thickness of (10.0 \(\pm\) 0.5 \(\upmu\)m). The inset is their corresponding visual images, Figure S3: Normalised IPCE,s of SANP-S and SANP-T devices sensitized with N719 and D149 highlighting scattering effects on IPCE responses and; Table S1: J-V parameters details of devices based on synthesized SANP-S and SANP-T sensitized either with D149 or N719.  
Conceptualization, K.A.-A. and A.N.; endothelium, K.A.-A.; software, K.A.-A.; validation, K.A.-A., A.N. and J.H.K.; formal analysis, K.A.-A.; investigation, K.A.-A.; resources, K.A.-A.; data curation, K.A.-A.; writing--original draft preparation, K.A.-A.; writing--review and editing, K.A.-A., A.N. and J.H.K.; visualization, K.A.-A. and A.N.; supervision, J.H.K., A.N. and S.X.D.; project administration, K.A.-A., A.N. and J.H.K.; funding acquisition, K.A.-A., A.N. and J.H.K.  
This research was conducted with funds from the Australian Research Council (DE160100504), as well as the Higher Committee for Education Development in Iraq (HCED).  
The authors would like to acknowledge the Electron Microscope Centre (EMC) and Australian National Fabrication Facility (ANFF) for access to equipment. In particular [PERSON] would like to thank [PERSON] for her assistance.  
The authors declare no conflict of interest