Supporting Information Aqueous, screen-printable paste for fabrication of mesoporous composite anatase-rutile TiO 2 nanoparticle thin films for (photo)electrochemical devices Amrita Yasin, Fuqiang Guo, George P. Demopoulos* Department of Mining and Materials Engineering, McGill University *Corresponding author. Email: george.demopoulos@mcgill.ca Number of pages: 15 Number of figures: 7 Number of tables: 3
This document provides supporting information to the article, Aqueous, screen-printable paste for fabrication of mesoporous composite anatase-rutile TiO 2 nanoparticle thin films for (photo)electrochemical devices. Figure S1 presents X-Ray diffraction (XRD) patterns of the aqueous synthesized anatase (JCPDS 00-021-1272) and rutile (JCPDS 00-001-1292) [1] used in the paste formulation, while Table S1 lists the BET (Brunauer-Emmett-Teller) surface area and Figure S2 presents the SEM and TEM images of the particles. Figure S3 presents the J-V curves of dye-sensitized solar cells (DSSCs) assembled from TiO 2 powder and colloid, using the organic-medium protocol; the photovoltaic parameters are presented in Table 1 of the article. Figure S4 presents the thermogravimetric (TGA) analysis of Paste U7 showing ~20% TiO 2 loading. Table S2 (a) presents data corresponding to BJH (Barrett-Joyner-Halenda) desorption pore size distribution, and Table S2 (b) presents N 2 adsorption/desorption data used to determine BET (Brunauer Emmett Teller) surface area; the corresponding isotherms and pore size distribution curves are presented in Figure 5 of the manuscript. Figure S5 presents the cumulative pore volume determined through BJH desorption pore distribution analysis. Figure S6 presents the J-V curves of DSSCs presented in Table 4 of the article. Figure S7 (a) presents efficiency and adsorbed dye as a function of pore width, and Figure S7 (b) presents efficiency and adsorbed dye as a function of surface area for the sintered films. Both curves show no direct relationship between efficiency and dye adsorption. Table S3 (a) lists additional paste formulations that were fabricated and Table S3 (b) presents the photovoltaic parameters of the respective pastes. Addition of polyacrylic acid or Triton-X did not improve the photovoltaic performance (Paste V1, V2, V3). Paste U9 was constructed using ethanol as the only solvent to observe if using a solution of water and ethanol has an adverse effect. The efficiency obtained was 4.5%, while the efficiency obtained for Paste U7 (as listed in Table 4 of the article) was 4.43%. The efficiencies are similar, even as less ethanol is used in the proposed protocol. S1
Figure S1: (a) XRD pattern of anatase (b) XRD pattern of rutile Table S1: BET surface area and calculated equivalent primary particle diameter Anatase Rutile Surface area (m 2 /g) 232.5 72.7 Equivalent primary particle size (nm) 6.6 19.3 S2
Figure S2: (a) SEM image of dry anatase (b) TEM image of dry anatase (c) SEM image of dry rutile (d) TEM image of dry rutile. S4
Current (ma/cm 2 ) 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 J-V comparison of Powder & Gel DSSCs η=4.42% η=4.85% 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Voltage (V) Powder Gel Figure S3: Comparison of DSSC performance of cells made from TiO 2 powder and TiO 2 colloid following organic protocol Figure S4: A representative TGA conducted to determine TiO 2 loading (Paste U7) S4
Table S2 (a): Tabular data corresponding to BJH desorption pore size distribution. Paste U4, 0 g PEG (cm³/g) (cm³/g) Area (m²/g) Area(m²/g) Width Range (Å) Average Width (Å) 3341.1-1244.0 1491.3 0.003939 0.003939 0.106 0.106 1244.0-992.0 1089.2 0.004783 0.008722 0.176 0.281 992.0-882.3 930.5 0.005366 0.014088 0.231 0.512 882.3-449.3 534.1 0.052866 0.066954 3.959 4.471 449.3-260.0 304.9 0.0513 0.118254 6.731 11.202 260.0-220.9 237 0.01293 0.131184 2.182 13.384 220.9-174.5 191.9 0.015948 0.147133 3.325 16.709 174.5-145.6 157.2 0.010662 0.157795 2.713 19.422 145.6-124.7 133.4 0.008297 0.166092 2.489 21.911 124.7-108.0 115 0.007175 0.173267 2.496 24.406 108.0-86.2 94.4 0.010204 0.183471 4.324 28.73 86.2-71.9 77.6 0.007533 0.191005 3.882 32.612 71.9-61.4 65.7 0.006373 0.197377 3.88 36.492 61.4-53.7 57 0.005239 0.202617 3.679 40.171 53.7-46.6 49.5 0.006122 0.208739 4.942 45.113 46.6-41.7 43.8 0.005385 0.214124 4.92 50.032 41.7-37.1 39.1 0.010562 0.224686 10.809 60.842 37.1-33.3 35 0.011281 0.235967 12.905 73.746 33.3-29.8 31.3 0.005423 0.24139 6.93 80.676 29.8-25.9 27.5 0.004921 0.246311 7.156 87.832 25.9-24.0 24.9 0.002248 0.248559 3.616 91.448 24.0-21.4 22.5 0.002942 0.251501 5.223 96.67 21.4-18.5 19.7 0.002818 0.254319 5.731 102.401 Paste U2, 1 g PEG (cm³/g) (cm³/g) Area (m²/g) Area(m²/g) Width Range (Å) Average Width (Å) 1890.7-1018.4 1209.9 0.005477 0.005477 0.181 0.181 1018.4-762.9 853.6 0.004928 0.010405 0.231 0.412 S5
762.9-413.0 488.6 0.042096 0.052501 3.446 3.858 413.0-265.2 306.5 0.040097 0.092598 5.232 9.09 265.2-213.9 233.7 0.017186 0.109783 2.941 12.032 213.9-164.3 182.2 0.018409 0.128193 4.043 16.074 164.3-137.2 148.1 0.011299 0.139492 3.052 19.127 137.2-125.2 130.6 0.005292 0.144784 1.621 20.748 125.2-109.3 116.1 0.007541 0.152324 2.599 23.346 109.3-85.2 93.9 0.012582 0.164906 5.357 28.704 85.2-71.3 76.9 0.007807 0.172713 4.063 32.766 71.3-58.2 63.2 0.008477 0.181191 5.362 38.128 58.2-53.1 55.4 0.004118 0.185309 2.974 41.102 53.1-46.5 49.3 0.006642 0.191951 5.387 46.489 46.5-41.0 43.4 0.006214 0.198165 5.731 52.22 41.0-36.3 38.3 0.009382 0.207547 9.789 62.009 36.3-32.8 34.3 0.009077 0.216624 10.58 72.589 32.8-29.3 30.8 0.003799 0.220423 4.937 77.526 29.3-26.5 27.7 0.002287 0.22271 3.302 80.828 26.5-23.5 24.8 0.002201 0.224911 3.552 84.38 23.5-20.9 22 0.001752 0.226663 3.179 87.559 20.9-18.0 19.2 0.001449 0.228112 3.023 90.582 Paste T1, 1.5 g PEG (cm³/g) (cm³/g) Area (m²/g) Area(m²/g) Width Range (Å) Average Width (Å) 1806.9-1023.2 1209.3 0.003679 0.003679 0.122 0.122 1023.2-819.4 898.3 0.003641 0.00732 0.162 0.284 819.4-733.9 771.8 0.004102 0.011422 0.213 0.496 733.9-454.9 529.7 0.041754 0.053176 3.153 3.649 454.9-287.1 332.8 0.055348 0.108525 6.652 10.301 287.1-215.8 240.7 0.030112 0.138637 5.003 15.304 215.8-176.2 191.7 0.01707 0.155707 3.562 18.866 176.2-144.1 156.6 0.015703 0.17141 4.01 22.877 144.1-123.4 132 0.010362 0.181772 3.14 26.017 123.4-108.8 115.1 0.00757 0.189342 2.631 28.649 108.8-86.8 95.1 0.01228 0.201622 5.168 33.816 86.8-71.9 77.8 0.008898 0.21052 4.575 38.391 71.9-61.6 65.8 0.006597 0.217117 4.008 42.4 61.6-53.2 56.7 0.006025 0.223142 4.253 46.652 53.2-46.6 49.4 0.005917 0.229058 4.793 51.445 S6
46.6-41.7 43.8 0.005554 0.234612 5.068 56.513 41.7-37.2 39.1 0.010042 0.244655 10.264 66.777 37.2-33.3 35 0.010069 0.254724 11.513 78.29 33.3-29.8 31.3 0.004991 0.259715 6.377 84.667 29.8-25.9 27.5 0.004453 0.264167 6.475 91.141 25.9-24.0 24.9 0.002019 0.266187 3.247 94.388 24.0-21.4 22.5 0.00258 0.268767 4.579 98.967 21.4-18.5 19.7 0.002342 0.271109 4.762 103.729 Paste U7, 2 g PEG (cm³/g) (cm³/g) Area (m²/g) Area(m²/g) Width Range (Å) Average Width (Å) 2382.7-1190.9 1423.6 0.003828 0.003828 0.108 0.108 1190.9-953.0 1045.1 0.004373 0.008202 0.167 0.275 953.0-833.9 885.3 0.004838 0.013039 0.219 0.494 833.9-447.6 530.1 0.054637 0.067676 4.122 4.616 447.6-270.3 315.3 0.051332 0.119009 6.512 11.128 270.3-214.7 235.7 0.02036 0.139369 3.455 14.583 214.7-173.1 189.1 0.015505 0.154875 3.28 17.863 173.1-139.1 152.1 0.013719 0.168594 3.609 21.472 139.1-119.4 127.6 0.008511 0.177105 2.668 24.139 119.4-109.8 114.2 0.004382 0.181487 1.535 25.674 109.8-85.5 94.3 0.011875 0.193362 5.035 30.71 85.5-71.7 77.3 0.007506 0.200868 3.886 34.596 71.7-61.3 65.6 0.006635 0.207503 4.046 38.642 61.3-52.9 56.4 0.007031 0.214534 4.987 43.629 52.9-46.3 49.1 0.007459 0.221993 6.082 49.711 46.3-41.3 43.4 0.00647 0.228463 5.956 55.667 41.3-36.9 38.8 0.010291 0.238754 10.612 66.278 36.9-33.1 34.7 0.011276 0.25003 12.994 79.272 33.1-29.5 31 0.004377 0.254407 5.642 84.914 29.5-25.7 27.3 0.003487 0.257894 5.112 90.026 25.7-23.8 24.6 0.0016 0.259494 2.598 92.624 23.8-21.1 22.3 0.001858 0.261351 3.337 95.961 21.1-18.2 19.4 0.001451 0.262802 2.993 98.954 Paste U5, 2.5 g Width Range (Å) Average Width (Å) Area (m²/g) Area(m²/g) S7
(cm³/g) (cm³/g) 3061.2-1318.0 1583.6 0.007212 0.007212 0.182 0.182 1318.0-907.4 1037.5 0.006921 0.014132 0.267 0.449 907.4-772.4 828.7 0.007377 0.02151 0.356 0.805 772.4-434.9 512.7 0.041799 0.063308 3.261 4.066 434.9-258.3 302 0.04415 0.107458 5.848 9.914 258.3-217.5 234.2 0.012846 0.120305 2.194 12.108 217.5-163.5 182.3 0.018652 0.138957 4.092 16.199 163.5-135.7 146.7 0.010515 0.149472 2.866 19.065 135.7-125.7 130.3 0.0042 0.153671 1.289 20.355 125.7-108.8 115.9 0.007413 0.161085 2.558 22.913 108.8-85.5 94 0.011278 0.172362 4.798 27.711 85.5-72.6 77.9 0.006595 0.178957 3.388 31.099 72.6-58.2 63.6 0.008524 0.187482 5.359 36.458 58.2-53.3 55.5 0.003691 0.191172 2.659 39.118 53.3-46.7 49.5 0.006054 0.197227 4.893 44.01 46.7-41.3 43.6 0.006144 0.203371 5.637 49.647 41.3-36.5 38.5 0.010447 0.213818 10.846 60.493 36.5-32.9 34.5 0.009689 0.223507 11.235 71.728 32.9-29.5 31 0.004559 0.228066 5.883 77.611 29.5-26.7 27.9 0.002966 0.231031 4.249 81.86 26.7-23.8 25 0.002908 0.23394 4.65 86.51 23.8-21.2 22.3 0.002376 0.236316 4.265 90.775 21.2-18.2 19.4 0.002217 0.238533 4.567 95.341 (b) N 2 adsorption/desorption data used for BET surface area analysis Relative Pressure (p/p ) Paste U4, 0 g PEG Absolute Quantity Pressure Adsorbed (mmhg) (cm³/g STP) Relative Pressure (p/p ) Paste U2, 1 g PEG Absolute Quantity Pressure Adsorbed (mmhg) (cm³/g STP) 0.00987 7.58149 15.00570 0.01049 8.05273 13.41710 0.03071 23.60313 17.21660 0.02883 22.13664 15.08060 0.05867 45.08292 18.97370 0.06198 47.58676 16.82070 0.07654 58.81480 19.90160 0.07812 59.98381 17.51610 0.09837 75.58861 20.95570 0.09898 76.00226 18.35060 0.11833 90.93131 21.86810 0.11891 91.30445 19.11030 0.13820 106.19414 22.75250 0.13878 106.56649 19.85150 0.15811 121.49025 23.61830 0.15868 121.85530 20.58170 0.17801 136.78636 24.47870 0.17863 137.17758 21.30320 S8
0.19802 152.15569 25.33780 0.19854 152.47308 22.03020 0.24853 190.96175 27.50970 0.24536 188.43259 23.73890 0.29627 227.64445 29.60530 0.29707 228.15404 25.66690 0.34668 266.37064 31.90880 0.34735 266.78439 27.63270 0.39552 303.89868 34.25800 0.39633 304.41736 29.66660 0.44505 341.94592 36.77410 0.44583 342.45193 31.87450 0.49445 379.89331 39.46090 0.49522 380.40622 34.29580 0.54489 418.63947 42.37110 0.54482 418.53455 36.95280 0.59957 460.64053 45.77370 0.59422 456.50220 39.86150 0.64385 494.65408 48.75730 0.64371 494.55017 43.04940 0.69719 535.61676 52.87020 0.69850 536.69482 47.19220 0.74750 574.24976 57.38280 0.74796 574.74951 51.90910 0.79679 612.09729 62.48960 0.79682 612.34900 57.81320 0.81695 627.57312 64.87750 0.81674 627.69806 60.57760 0.84409 648.41394 68.56840 0.84329 648.14111 64.67780 0.87340 670.90546 73.61800 0.87290 670.97394 70.27650 0.89414 686.82062 78.25080 0.89280 686.32300 75.01150 0.91942 706.21033 85.86090 0.91984 707.19452 83.71480 0.94444 725.44696 97.27160 0.94424 726.05115 95.77650 0.97097 745.85510 121.58710 0.96911 745.26929 120.24060 0.97474 748.77051 128.43030 0.97555 750.24280 130.64600 0.98417 756.05914 151.77390 0.98843 760.14972 138.79250 0.99424 763.80701 161.57060 0.98976 761.18060 145.40800 0.98432 756.19226 159.15130 0.98077 754.27252 142.07810 0.98024 753.06384 156.26220 0.97414 749.17847 139.14400 0.97772 751.13348 153.05570 0.95121 731.57361 115.32700 0.95525 733.92041 122.90470 0.92257 709.58423 93.65900 0.92081 707.50165 95.21370 0.90306 694.60333 84.49310 0.90608 696.20593 88.25040 0.87236 671.00739 74.80100 0.87980 676.03748 79.71820 0.84605 650.79193 68.85530 0.85479 656.84076 73.99440 0.83084 639.09772 66.05630 0.82949 637.39783 69.52220 0.80554 619.65198 62.07500 0.80228 616.49048 65.63960 0.74974 576.73755 55.42960 0.75155 577.50470 60.09160 0.70174 539.82758 51.18530 0.70242 539.75031 55.93730 0.63739 490.33304 46.56280 0.65295 501.74301 52.42600 0.60537 465.70627 44.39340 0.60650 466.04544 49.54560 0.55507 427.01569 41.04980 0.55160 423.85800 46.32820 0.50358 387.40802 37.92630 0.50560 388.51318 43.65670 0.45100 346.96362 33.93170 0.45545 349.98004 39.46960 0.40442 311.13132 30.22620 0.40597 311.95276 35.16000 0.35291 271.50357 27.83080 S9
0.35385 271.90198 32.34200 0.30631 235.65117 25.98150 0.28852 221.70706 29.31590 0.25294 194.59094 23.97390 0.25379 195.01541 27.78540 0.20193 155.35146 22.10720 0.20308 156.04961 25.59690 0.14183 109.11685 19.92760 0.14292 109.82181 23.01310 Relative Pressure (p/p ) Paste T1, 1.5 g PEG Absolute Quantity Pressure Adsorbed (mmhg) (cm³/g STP) Relative Pressure (p/p ) Paste U7, 2 g PEG Absolute Quantity Pressure Adsorbed (mmhg) (cm³/g STP) 0.00973 7.46663 15.74260 0.01025 7.82562 14.95920 0.03011 23.11868 17.96670 0.03084 23.54501 16.97520 0.05789 44.45279 19.71400 0.05888 44.95238 18.57800 0.07637 58.64249 20.65810 0.07683 58.65805 19.42510 0.09834 75.51522 21.69110 0.09862 75.30066 20.36770 0.11827 90.82646 22.58560 0.11858 90.54295 21.19050 0.13813 106.07574 23.45140 0.13846 105.72329 21.98320 0.15802 121.36220 24.30250 0.15835 120.91602 22.76480 0.17791 136.64246 25.15100 0.17830 136.15211 23.53920 0.19786 151.97229 25.99440 0.19828 151.41299 24.31360 0.24830 190.72443 28.15420 0.24343 185.89404 26.08820 0.29588 227.27684 30.24490 0.29623 226.21797 28.23770 0.34621 265.95462 32.55480 0.34693 264.94333 30.40530 0.39481 303.30637 34.90010 0.39545 302.00192 32.63260 0.44421 341.27774 37.41630 0.44488 339.76688 35.08600 0.49344 379.11902 40.10230 0.49417 377.42032 37.77650 0.54305 417.27008 42.98940 0.54357 415.16666 40.75600 0.59788 459.43643 46.46990 0.59950 457.90707 44.48580 0.64772 497.77960 50.05840 0.64326 491.34717 47.70080 0.69646 535.28625 54.18080 0.69740 532.73059 52.12960 0.74479 572.48309 59.07790 0.74584 569.76447 56.94800 0.79325 609.79144 64.96630 0.79569 607.88257 62.97450 0.81480 626.41016 67.98840 0.81664 623.91174 65.87810 0.84631 650.71234 73.22590 0.84343 644.40833 69.95820 0.87202 670.56549 78.81020 0.87245 666.62738 75.43280 0.89792 690.52405 86.32320 0.89888 686.85748 82.11490 0.92169 708.82813 96.12870 0.92398 706.02191 91.13350 0.94375 725.82477 110.01040 0.94781 724.21973 104.58750 0.97200 747.58643 144.77540 0.97080 741.76691 129.64790 0.97435 749.40820 151.53420 0.97440 744.51178 136.27080 0.98880 760.54309 168.31790 0.99084 757.05878 163.44390 S10
0.98928 760.91486 172.59110 0.99190 757.86426 167.54780 0.98086 754.44586 170.35630 0.98361 751.53192 165.20070 0.97596 750.68463 168.18430 0.97942 748.32239 162.56480 0.97308 748.47253 165.76690 0.97640 746.01123 159.68130 0.95583 735.24329 141.99010 0.95511 729.72180 128.52270 0.92861 714.34290 111.96290 0.92402 705.95374 100.66390 0.90373 695.23328 95.97960 0.90337 690.16620 89.74270 0.88102 677.79047 86.93050 0.87893 671.49750 81.43110 0.85322 656.40680 78.67290 0.84807 647.92151 74.07760 0.82767 636.75189 73.15940 0.82213 628.10028 69.46770 0.80379 618.37964 69.08190 0.80617 615.90649 67.07650 0.75320 579.46021 62.43430 0.75023 573.17230 60.57330 0.70246 540.42303 57.47710 0.70265 536.82001 56.36950 0.65399 503.13327 53.69750 0.65405 499.68707 52.68660 0.60275 463.71191 50.24520 0.60254 460.33591 48.98440 0.55194 424.61899 47.01170 0.55127 421.16446 45.30770 0.50624 389.46695 44.14610 0.50465 385.54953 42.16730 0.45611 350.90073 39.95490 0.45551 348.00763 37.92540 0.40602 312.36545 35.82900 0.40615 310.29224 33.46250 0.35410 272.41742 33.02110 0.35367 270.19757 30.77370 0.28859 222.02231 29.98630 0.28962 221.26732 28.00650 0.25414 195.51422 28.46190 0.25389 193.96750 26.54330 0.20325 156.36552 26.27210 0.20276 154.90758 24.52040 0.14324 110.19633 23.71010 0.14270 109.01959 22.17920 Paste U5, 2.5 g PEG Relative Pressure (p/p ) Absolute Pressure (mmhg) Quantity Adsorbed (cm³/g STP) 0.00983 7.55080 13.96290 0.03293 25.30321 16.12430 0.06295 48.37732 17.78970 0.07827 60.14532 18.50250 0.09907 76.13052 19.41600 0.11899 91.43963 20.24920 0.13891 106.74204 21.05610 0.15883 122.05116 21.85170 0.17877 137.37366 22.63930 0.19874 152.71623 23.41980 0.24576 188.84358 25.27100 0.29747 228.57230 27.35110 0.34784 267.27014 29.45860 0.39689 304.95718 31.63850 S11
0.44663 343.17307 33.99100 0.49613 381.20151 36.52850 0.54592 419.45084 39.26620 0.59548 457.51947 42.20010 0.64506 495.60815 45.38050 0.69399 533.19476 48.97220 0.74916 575.56763 53.96420 0.80001 614.62024 59.60320 0.81880 629.04572 61.88390 0.84476 648.98041 65.56400 0.86952 667.99127 69.84120 0.90005 691.42017 76.76050 0.91911 706.04651 82.81280 0.94945 729.32141 98.20010 0.97052 745.48065 117.55790 0.97637 749.95221 128.58460 0.99326 762.92517 145.66450 0.99371 763.27325 151.74600 0.98522 756.75330 147.30290 0.97836 751.47845 143.12930 0.97446 748.48627 138.75210 0.95374 732.56799 114.96990 0.92033 706.90997 91.13870 0.90464 694.85419 84.24760 0.87149 669.39697 74.38330 0.84397 648.25745 68.79080 0.83122 638.46417 66.56340 0.80414 617.66602 62.61590 0.74980 575.92242 56.60390 0.70593 542.22498 52.97450 0.63619 488.65982 48.29370 0.60483 464.57489 46.33240 0.55444 425.86368 43.25740 0.50374 386.92487 40.25830 0.44974 345.44901 36.01890 0.40361 310.01114 32.23170 0.35249 270.75101 29.69280 0.30562 234.75084 27.69080 0.25266 194.07158 25.53940 0.20172 154.94533 23.53130 0.14177 108.89751 21.17010 S12
pore volume (cm 3 /g) 0.28 0.27 0.26 0.25 0.24 0.23 0.22 0 0.5 1 1.5 2 2.5 (U4) (U2) (T1) (U7) (U5) PEG quantity (g) Figure S5: pore volume as a function of PEG quantity for the sintered films. 10.0 J-V curves of DSSCs Current (ma/cm 2 ) 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 U7 U5 U4 U2 T1 0.0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Voltage (V) Figure S6: J-V curves of DSSC assembled from photoanode films prepared from variable PEG amount paste formulation. S13
a" Efficiency (%) Efficiency & Adsorbed Dye vs. Width 6.00 7.00E-05 5.50 0g 2.5g 2g 5.00 4.50 1.5g 4.00 1g 3.50 3.00 98.00 99.00 100.00 101.00 102.00 103.00 104.00 105.00 106.00 107.00 Width (Å) 6.50E-05 6.00E-05 5.50E-05 5.00E-05 4.50E-05 4.00E-05 3.50E-05 3.00E-05 2.50E-05 Adsorbed Dye (mol/cm 3 ) Efficiency Adsorbed dye b" Efficiency (%) 5.50 5.00 4.50 4.00 3.50 1g Efficiency & Adsorbed Dye vs. BET Surface Area 2g 2.5g 0g 1.5g 7.00E-05 6.50E-05 6.00E-05 5.50E-05 5.00E-05 4.50E-05 4.00E-05 3.50E-05 3.00E-05 3.00 2.50E-05 78.00 80.00 82.00 84.00 86.00 88.00 90.00 92.00 94.00 96.00 BET Surface Area (m 2 /g) Adsorbed Dye (mol/cm 3 ) Efficiency Adsorbed dye Figure S7: (a) Efficiency and dye loading as a function of pore width, (b) Efficiency and dye loading as a function of surface area; (amount of PEG is given next to each data point): 3g TiO 2 (Anatase 80%, Rutile 20%), 0.5mL Acetic acid, 10g PG, 50mL Water, 50mL Ethanol. S14
Table S3: (a) Additional paste formulations Paste PEG PG Additional component Quantity (g) Quantity (g) Component Quantity V1 2 10 Polyacrylic acid 2g V2 2 10 Triton-X 800 µl V3 2 10 Triton-X 400 µl U9* 0 10 - - *For U9, 95% ethanol, 5% water (volume basis) was used as solvent (b) Photovoltaic parameters corresponding to additional paste formulations Paste Thickness (µm) η (%) V oc (V) J sc (ma/cm 2 ) FF V1 13.78 2.51 0.72 5.21 66.71 V2 10.07 3.82 0.76 7.05 71.61 V3 12.14 3.08 0.73 6.65 63.24 U9 15.77 4.5 0.72 8.53 73.33 References 1. Charbonneau, C.; Gauvin, R.; Demopoulos, G.P. Aqueous Solution Synthesis of Crystalline Anatase Nanocolloids for the Fabrication of DSC Photoanodes. JES. 2011. 158 (3): p. H224-H231. S15