*Crystal Facet Engineering of TiO2 from Theory to Application DOI: http://dx.doi.org/10.5772/intechopen.111565*

[15] Gong XQ, Selloni A. First-principles study of the structures and energetics of stoichiometric brookite TiO2 surfaces. Physical Review B. Condensed Matter and Materials Physics. 2007;**76**(23):1-11

[16] Lin H, Li L, Zhao M, Huang X, Chen X, Li G, et al. Synthesis of highquality brookite TiO2 single-crystalline nanosheets with specific facets exposed: Tuning catalysts from inert to highly reactive. Journal of the American Chemical Society. 2012;**134**(20): 8328-8331

[17] Jiang HB, Cuan Q, Wen CZ, Xing J, Wu D, Gong XQ, et al. Anatase TiO2 crystals with exposed high-index facets. Angewandte Chemie - International Edition. 2011;**50**(16):3764-3768

[18] Wang Y, Sun T, Liu X, Zhang H, Liu P, Yang H, et al. Geometric structure of rutile titanium dioxide (111) surfaces. Physical Review B. Condensed Matter and Materials Physics. 2014;**90**(4):1-6

[19] Zhou G, Jiang L, Dong Y, Li R, He D. Engineering the exposed facets and open-coordinated sites of brookite TiO2 to boost the loaded Ru nanoparticle efficiency in benzene selective hydrogenation. Applied Surface Science. 2019;**486**:187-197

[20] Hengerer R, Bolliger B, Erbudak M, Grätzel M. Structure and stability of the anatase TiO2 (101) and (001) surfaces. Surface Science. 2000;**460**(1–3):162-169

[21] Liang Y, Gan S, Chambers SA, Altman EI. Surface structure of anatase (001) reconstruction, atomic steps, and domains. Physical Review B. Condensed Matter and Materials Physics. 2001; **63**(23):1-7

[22] Herman GS, Sievers MR, Gao Y. Structure determination of the two-Domain (1 x 4) Anatase TiO2 (001)

surface. Physical Review Letters. 2000; **84**:3354

[23] Wang Y, Sun H, Tan S, Feng H, Cheng Z, Zhao J, et al. Role of point defects on the reactivity of reconstructed anatase titanium dioxide (001) surface. Nature Communications. 2013;**4**:1-8

[24] Selçuk S, Selloni A. Surface structure and reactivity of anatase TiO2 crystals with dominant {001} facets. Journal of Physical Chemistry C. 2013;**117**(12): 6358-6362

[25] Yuan W, Wang Y, Li H, Wu H, Zhang Z, Selloni A, et al. Real-time observation of reconstruction dynamics on TiO2 (001) surface under oxygen via an environmental transmission electron microscope. Nano Letters. 2016;**16**(1): 132-137

[26] Yang HG, Sun CH, Qiao SZ, Zou J, Liu G, Smith SC, et al. Anatase TiO2 single crystals with a large percentage of reactive facets. Nature. 2008;**453**(7195): 638-641

[27] DeBenedetti WJI, Skibinski ES, Jing D, Song A, Hines MA. Atomic-scale understanding of catalyst activation: Carboxylic acid solutions, but not the acid itself, increase the reactivity of Anatase (001) faceted Nanocatalysts. Journal of Physical Chemistry C. 2018; **122**(8):4307-4314

[28] Wang Y, Lee S, Vilmercati P, Lee HN, Weitering HH, Snijders PC. Atomically flat reconstructed rutile TiO2 (001) surfaces for oxide film growth. Applied Physics Letters. 2016;**108**(9): 091604

[29] Tait RH, Kasowski RV. Ultraviolet photoemission and low-energy-electron diffraction studies of TiO2 (rutile) (001) and (110) surfaces. Physical Review B. 1979;**20**(12):5178-5191

[30] Firment LE. Thermal faceting of the rutile TiO2 (001) surface. Surface Science. 1982;**116**(2):205-216

[31] Zhou R, Li D, Qu B, Sun X, Zhang B, Zeng XC. Rutile TiO2 (011)-2 1 reconstructed surfaces with optical absorption over the visible light Spectrum. ACS Applied Materials & Interfaces. 2016;**8**(40):27403-27410

[32] Wu L, Wang Z, Xiong F, Sun G, Chai P, Zhang Z, et al. Surface chemistry and photochemistry of small molecules on rutile TiO2 (001) and TiO2 (011)- (2 1) surfaces: The crucial roles of defects. The Journal of Chemical Physics. 2020;**152**:044702

[33] Gong XQ, Khorshidi N, Stierle A, Vonk V, Ellinger C, Dosch H, et al. The 2 1 reconstruction of the rutile TiO2(0 1 1) surface: A combined density functional theory, X-ray diffraction, and scanning tunneling microscopy study. Surface Science. 2009;**603**:138-144

[34] Balzaretti F, Gupta V, Ciacchi LC, Aradi B, Frauenheim T, Köppen S. Water reactions on reconstructed rutile TiO2: A density functional theory/ density functional tight binding approach. Journal of Physical Chemistry C. 2021;**125**(24): 13234-13246

[35] Wulff G. Zur Frage der Geschwindigkeit des Wachsthums und der Auflösung der Krystallflächen. Zeitschrift für Krystallographie und Mineralogie. 1901;**34**:449-530

[36] Huang Z, Wang Z, Lv K, Zheng Y, Deng K. Transformation of TiOF2 cube to a hollow nanobox assembly from anatase TiO2 nanosheets with exposed {001} facets via solvothermal strategy. ACS Applied Materials & Interfaces. 2013;**5**(17):8663-8669

[37] Dudziak S, Kowalkińska M, Karczewski J, Pisarek M, Siuzdak K, Kubiak A, et al. Solvothermal growth of {0 0 1} exposed anatase nanosheets and their ability to mineralize organic pollutants. The effect of alcohol type and content on the nucleation and growth of TiO2 nanostructures. Applied Surface Science. 2021;**563**:150360

[38] Amano F, Yasumoto T, Prieto-Mahaney OO, Uchida S, Shibayama T, Ohtani B. Photocatalytic activity of octahedral single-crystalline mesoparticles of anatase titanium(IV) oxide. Chemical Communications. 2009; **17**:2311-2313

[39] Li J, Yu Y, Chen Q, Li J, Xu D. Controllable synthesis of TiO2 single crystals with tunable shapes using ammonium-exchanged titanate nanowires as precursors. Crystal Growth & Design. 2010;**10**(5):2111-2115

[40] Lai Z, Peng F, Wang Y, Wang H, Yu H, Liu P, et al. Low temperature solvothermal synthesis of anatase TiO2 single crystals with wholly {100} and {001} faceted surfaces. Journal of Materials Chemistry. 2012;**22**(45): 23906-23912

[41] Kowalkińska M, Dudziak S, Karczewski J, Ryl J, Trykowski G, Zielińska-Jurek A. Facet effect of TiO2 nanostructures from TiOF2 and their photocatalytic activity. Chemical Engineering Journal. 2021;**404**:126493

[42] Gai L, Mei Q, Qin X, Li W, Jiang H, Duan X. Controlled synthesis of anatase TiO2 octahedra with enhanced photocatalytic activity. Materials Research Bulletin. 2013;**48**: 4469-4475

[43] Wang F, Sun L, Li Y, Zhan W, Wang X, Han X. Hollow Anatase TiO2 Octahedrons with Exposed High-Index

## *Crystal Facet Engineering of TiO2 from Theory to Application DOI: http://dx.doi.org/10.5772/intechopen.111565*

{102} Facets for Improved Dye-Sensitized Photoredox Catalysis Activity. Inorganic Chemistry. 2018;**57**(8): 4550-4555

[44] Xu H, Ouyang S, Li P, Kako T, Ye J. High-active anatase TiO2 nanosheets exposed with 95% {100} facets toward efficient H2 evolution and CO2 photoreduction. ACS Applied Materials & Interfaces. 2013;**5**(4):1348-1354

[45] Li J, Xu D. Tetragonal facetednanorods of anatase TiO2 single crystals with a large percentage of active {100} facets. Chemical Communications. 2010; **46**(13):2301-2303

[46] Wen CZ, Zhou JZ, Jiang HB, Hu QH, Qiao SZ, Yang HG. Synthesis of microsized titanium dioxide nanosheets wholly exposed with high-energy {001} and {100} facets. Chemical Communications. 2011;**47**(15): 4400-4402

[47] Yang HG, Liu G, Qiao SZ, Sun CH, Jin YG, Smith SC, et al. Solvothermal synthesis and photoreactivity of anatase TiO2 nanosheets with dominant {001} facets. Journal of the American Chemical Society. 2009;**131**(11):4078-4083

[48] Zheng Y, Wang J, Yang P. Anatase TiO2 nanosheets exposed {001} facet: Solvent effects on the photocatalytic performance. Journal of Nanoscience and Nanotechnology. 2017;**17**(2): 1204-1209

[49] Li Q, Li T, Chang S, Tao Q, Tian B, Zhang J. Enlarging {110} exposed facets of anatase TiO2 by the synergistic action of capping agents. Cryst Eng Comm. 2016;**18**(27):5074-5078

[50] Xu H, Reunchan P, Ouyang S, Tong H, Umezawa N, Kako T, et al. Anatase TiO2 single crystals exposed with high-reactive {111} facets toward efficient H2 evolution. Chemistry of Materials. 2013;**25**(3):405-411

[51] Lai Z, Peng F, Wang H, Yu H, Zhang S, Zhao H. A new insight into regulating high energy facets of rutile TiO2. Journal of Materials Chemistry A. 2013;**1**(13):4182-4185

[52] Kobayashi M, Petrykin V, Kakihana M, Tomita K. Hydrothermal synthesis and photocatalytic activity of whisker-like rutile-type titanium dioxide. Journal of the American Ceramic Society. 2009;**92**:S21-S26

[53] Wu T, Kang X, Kadi MW, Ismail I, Liu G, Cheng HM. Enhanced photocatalytic hydrogen generation of mesoporous rutile TiO2 single crystal with wholly exposed {111} facets. Chinese Journal of Catalysis. 2015;**36**: 2103-2108

[54] Truong QD, Hoa HT, Le TS. Rutile TiO2 nanocrystals with exposed {3 3 1} facets for enhanced photocatalytic CO2 reduction activity. Journal of Colloid and Interface Science. 2017;**504**:223-229

[55] Chen JS, Lou XW. Unusual rutile TiO2 nanosheets with exposed (001) facets. Chemical Science. 2011;**2**(11): 2219-2223

[56] Perego C, Wang YH, Durupthy O, Cassaignon S, Revel R, Jolivet JP. Nanocrystalline brookite with enhanced stability and photocatalytic activity: Influence of lanthanum (III) doping. ACS Applied Materials & Interfaces. 2012;**4**(2):752-760

[57] Xu Y, Lin H, Li L, Huang X, Li G. Precursor-directed synthesis of wellfaceted brookite TiO2 single crystals for efficient photocatalytic performances. Journal of Materials Chemistry A. 2015; **3**(44):22361-22368

[58] Shi T, Duan Y, Lv K, Hu Z, Li Q, Li M, et al. Photocatalytic oxidation of acetone over high thermally stable TiO2 nanosheets with exposed (001) facets. Frontiers in Chemistry. 2018;**6**(MAY): 1-10

[59] Liu M, Piao L, Zhao L, Ju S, Yan Z, He T, et al. Anatase TiO2 single crystals with exposed {001} and {110} facets: Facile synthesis and enhanced photocatalysis. Chemical Communications. 2010;**46**(10): 1664-1666

[60] Zhao M, Xu H, Chen H, Ouyang S, Umezawa N, Wang D, et al. Photocatalytic reactivity of {121} and {211} facets of brookite TiO2 crystals. Journal of Materials Chemistry A. 2015; **3**(5):2331-2337

[61] Pan J, Liu G, Lu GQ, Cheng HM. On the true photoreactivity order of {001}, {010}, and {101} facets of anatase TiO2 crystals. Angewandte Chemie - International Edition. 2011;**50**(9): 2133-2137

[62] Ye L, Mao J, Peng T, Zan L, Zhang Y. Opposite photocatalytic activity orders of low-index facets of anatase TiO2 for liquid phase dye degradation and gaseous phase CO2 photoreduction. Physical Chemistry Chemical Physics. 2014;**16**(29):15675-15680

[63] Mao J, Ye L, Li K, Zhang X, Liu J, Peng T, et al. Pt-loading reverses the photocatalytic activity order of anatase TiO2 {001} and {010} facets for photoreduction of CO2 to CH4. Applied Catalysis B: Environmental. 2014;**144**: 855-862

[64] Li M, Chen Y, Li W, Li X, Tian H, Wei X, et al. Ultrathin anatase TiO2 nanosheets for high-performance photocatalytic hydrogen production. Small. 2017;**13**(16):1604115

[65] Xiang Q, Lv K, Yu J. Pivotal role of fluorine in enhanced photocatalytic activity of anatase TiO2 nanosheets with dominant (0 0 1) facets for the photocatalytic degradation of acetone in air. Applied Catalysis B: Environmental. 2010;**96**(3–4):557-564

[66] Wu Q, Liu M, Wu Z, Li Y, Piao L. Is photooxidation activity of {001} facets truly lower than that of {101} facets for anatase TiO2 crystals? Journal of Physical Chemistry C. 2012;**116**(51):26800-26804

[67] Gordon TR, Cargnello M, Paik T, Mangolini F, Weber RT, Fornasiero P, et al. Nonaqueous synthesis of TiO2 nanocrystals using TiF4 to engineer morphology, oxygen vacancy concentration, and photocatalytic activity. Journal of the American Chemical Society. 2012;**134**(15): 6751-6761

[68] Mino L, Pellegrino F, Rades S, Radnik J, Hodoroaba VD, Spoto G, et al. Beyond Shape Engineering of TiO2 Nanoparticles: Post-Synthesis Treatment Dependence of Surface Hydration, Hydroxylation, Lewis Acidity and Photocatalytic Activity of TiO2 Anatase Nanoparticles with Dominant {001} or {101} Facets. ACS Applied Nano Materials. 2018;**1**(9):5355-5365

[69] Günnemann C, Haisch C, Fleisch M, Schneider J, Emeline AV, Bahnemann DW. Insights into different photocatalytic oxidation activities of Anatase, Brookite, and rutile singlecrystal facets. ACS Catalysis. 2019;**9**(2): 1001-1012

[70] Amalia FR, Takashima M, Ohtani B. Are you still using organic dyes? Colorimetric formaldehyde analysis for true photocatalytic-activity evaluation. Chemical Communications. 2022;**58**: 11721-11724

*Crystal Facet Engineering of TiO2 from Theory to Application DOI: http://dx.doi.org/10.5772/intechopen.111565*

[71] Agrios AG, Pichat P. Recombination rate of photogenerated charges versus surface area: Opposing effects of TiO2 sintering temperature on photocatalytic removal of phenol, anisole, and pyridine in water. Journal of Photochemistry and Photobiology A: Chemistry. 2006;**180**(1– 2):130-135

[72] Lv K, Guo X, Wu X, Li Q, Ho W, Li M, et al. Photocatalytic selective oxidation of phenol to produce dihydroxybenzenes in a TiO2/UV system: Hydroxyl radical versus hole. Applied Catalysis B: Environmental. 2016;**199**:405, 405-411, 411. DOI: 10.1016/j.apcatb.2016.06.049

[73] Bahnemann DW, Hilgendorff M, Memming R. Charge carrier dynamics at TiO2 particles: Reactivity of free and trapped holes. The Journal of Physical Chemistry. A. 1997;**101**(21):4265-4275

[74] Ma X, Dai Y, Guo M, Huang B. Relative photooxidation and photoreduction activities of the {100}, {101}, and {001} Surfaces of Anatase TiO2. Langmuir. 2013;**29**(44): 13647-13654

[75] Antunes CSA, Bietti M, Salamone M, Scione N. Early stages in the TiO2 photocatalyzed degradation of simple phenolic and non-phenolic lignin model compounds. Journal of Photochemistry and Photobiology A: Chemistry. 2004; **163**(3):453-462

[76] Setvin M, Aschauer U, Hulva J, Simschitz T, Daniel B, Schmid M, et al. Following the reduction of oxygen on TiO2 Anatase (101) step by step. Journal of the American Chemical Society. 2016; **138**(30):9565-9571

[77] Chen J, Li YF, Sit P, Selloni A. Chemical dynamics of the first protoncoupled electron transfer of water oxidation on TiO2 anatase. Journal of the American Chemical Society. 2013; **135**(50):18774-18777

[78] Hwang JY, Hee MG, Kim B, Tachikawa T, Majima T, Hong S, et al. Crystal phase-dependent generation of mobile OH radicals on TiO2: Revisiting the photocatalytic oxidation mechanism of anatase and rutile. Applied Catalysis B: Environmental. 2021;**November 2020**(286):119905

[79] Dudziak S, Kowalkińska M, Karczewski J, Pisarek M, Gouveia JD, Gomes JRB, et al. Surface and trapping energies as predictors for the photocatalytic degradation of aromatic organic pollutants. Journal of Physical Chemistry C. 2022;**126**: 14859-14877

[80] Kowalkińska M, Sikora K, Łapiński M, Karczewski J, Zielińska-Jurek A. Non-toxic fluorine-doped TiO2 nanocrystals from TiOF2 for facetdependent naproxen degradation. Catalysis Today. 2022;**413–415**:113959

[81] Wang Y, Mino L, Pellegrino F, Homs N, Ramírez de la Piscina P. Engineered MoxC/TiO2 interfaces for efficient noble metal-free photocatalytic hydrogen production. Applied Catalysis B: Environmental. 2022;**318**:121783

[82] Wang D, Gong XQ. Functionoriented design of robust metal cocatalyst for photocatalytic hydrogen evolution on metal/titania composites. Nature Communications. 2021;**12**:1-6

[83] Wei Z, Janczarek M, Endo M, Wang K, Balčytis A, Nitta A, et al. Noble metal-modified faceted anatase titania photocatalysts: Octahedron versus decahedron. Applied Catalysis B: Environmental. 2018;**237**:574-587

[84] Meng A, Zhang J, Xu D, Cheng B, Yu J. Enhanced photocatalytic H2-production activity of anatase TiO2 nanosheet by selectively depositing dualcocatalysts on (101) and (001) facets. Applied Catalysis B: Environmental. 2016;**198**:286-294

[85] Mishra SB, Nanda BRK. Facet dependent catalytic activities of anatase TiO2 for CO2 adsorption and conversion. Applied Surface Science. 2020;**531**:147330

[86] Ma S, Song W, Liu B, Zhong W, Deng J, Zheng H, et al. Facet-dependent photocatalytic performance of TiO2: A DFT study. Applied Catalysis B: Environmental. 2016;**198**:1-8

[87] Liu L, Jiang Y, Zhao H, Chen J, Cheng J, Yang K, et al. Engineering Coexposed {001} and {101} Facets in Oxygen-Deficient TiO2 Nanocrystals for Enhanced CO2 Photoreduction under Visible Light. ACS Catalysis. 2016;**6**(2): 1097-1108

[88] Yu J, Low J, Xiao W, Zhou P, Jaroniec M. Enhanced Photocatalytic CO2-Reduction Activity of Anatase TiO2 by Co-exposed {001} and {101} Facets. Journal of the American Chemical Society. 2014;**136**:8839

[89] Keller N, Ivanez J, Highfield J, Ruppert AM. Photo/thermal synergies in heterogeneous catalysis: Towards lowtemperature (solar-driven) processing for sustainable energy and chemicals. Applied Catalysis B: Environmental. 2021;**296**:120320

[90] Fang F, Liu Y, Sun X, Fu C, Prakash Bhoi Y, Xiong W, et al. TiO2 facetdependent reconstruction and photocatalysis of CuOx/TiO2 photocatalysts in CO2 photoreduction. Applied Surface Science. 2021;**564**:150407

[91] Feng N, Lin H, Song H, Yang L, Tang D, Deng F, et al. Efficient and selective photocatalytic CH4 conversion to CH3OH with O2 by controlling overoxidation on TiO2. Nature Communications. 2021;**12**(1):4652 **Chapter 4**
