1. J.L. Blauch, S.M. Tarka, HPLC determination of caffeine and theobromine in coffee, tea, and instant hot cocoa mixes, J. Food Sci., 48 (1983) 745–747.
  2. H. Sereshti, S. Samadi, A rapid and simple determination of caffeine in teas, coffees and eight beverages, Food Chem., 158 (2014) 8–13.
  3. X. Jun, Caffeine extraction from green tea leaves assisted by high pressure processing, J. Food Eng., 94 (2009) 105–109.
  4. O. Cauli, M. Morelli, Caffeine and the dopaminergic system, Behav. Pharmacol., 16 (2005) 63–77.
  5. J.Y. Sun, K.J. Huang, S.Y. Wei, Z.W. Wu, F.P. Ren, A graphenebased electrochemical sensor for sensitive determination of caffeine, Colloids Surf. B: Biointerfaces., 84 (2011) 421–426.
  6. P. Sriamornsak, R.A. Kennedy, Effect of drug solubility on release behavior of calcium polysaccharide gel-coated pellets, Eur. J. Pharm. Sci., 32 (2007) 231–239.
  7. F. Sodré, M. Locatelli, W. Jardim, Occurrence of emerging contaminants in brazilian drinking waters: a sewage-to-tap issue, Water Air Soil Pollut., 206 (2010) 57–67.
  8. C. Wang, Y. Le, B. Cheng, Fabrication of porous ZrO2 hollow sphere and its adsorption performance to Congo red in water, Ceram. Int., 40 (2014) 10847–10856.
  9. T.K.F.S. Freitas, V.M. Oliveira, M.T.F. De Souza, H.C.L. Geraldino, V.C. Almeida, S.L. Fávaro, J.C. Garcia, Optimization of coagulation-flocculation process for treatment of industrial textile wastewater using okra (A. esculentus) mucilage as natural coagulant, Ind. Crops Prod., 76 (2015) 538–544.
  10. M. Taheran, S.K. Brar, M. Verma, R.Y. Surampalli, T.C. Zhang, R.J. Valero, Membrane processes for removal of pharmaceutically active compounds (PhACs) from water and wastewaters, Sci. Total Environ., 547 (2016) 60–77.
  11. B. Bonakdarpour, I. Vyrides, D.C. Stuckey, Comparison of the performance of one stage and two stage sequential anaerobice aerobic biological processes for the treatment of reactive-azo-dye-containing synthetic wastewaters, Int. Biodeterior. Biodegrad., 65 (2011) 591–599.
  12. A. Elhalil, H. Tounsadi, R. Elmoubarki, F.Z. Mahjoubi, M. Farnane, M. Sadiq, M. Abdennouri, S. Qourzal, N. Barka, Factorial experimental design for the optimization of catalytic degradation of malachite green dye in aqueous solution by Fenton process, Water Resour. Ind., 15 (2016) 41–48.
  13. M. Abdennouri, A. Elhalil, M. Farnane, H. Tounsadi, F.Z. Mahjoubi, R. Elmoubarki, M. Sadiq, L. Khamar, A. Galadi, M. Baâlala, M. Bensitel, Y. El Hafiane, A. Smith, N. Barka, Photocatalytic degradation of 2,4-D and 2,4-DP herbicides on Pt/TiO nanoparticles, J. Saudi Chem. Soc., 19 (2015) 485–493.
  14. X.Q. Deng, X. Zhu, Z.G. Sun, X.S. Li, J.L. Liu, C. Shi, A.M. Zhu, Exceptional activity for photocatalytic mineralization of formaldehyde over amorphous titania nanofilms, Chem. Eng. J., 306 (2016) 1001–1009.
  15. C. Diaz-Uribe, W. Vallejo, W. Ramos, Methylene blue photocatalytic mineralization under visible irradiation on TiO2 thin films doped with chromium, Appl. Surf. Sci., 319 (2014) 121– 127.
  16. G. Liao, D. Zhu, J. Zheng, J. Yin, B. Lan, L. Li, Efficient mineralization of bisphenol A by photocatalytic ozonation with TiO2–graphene hybrid, J. Taiwan Inst. Chem. Eng., 67 (2016) 300–305.
  17. H.L. Shen, H.H. Hu, D.Y. Liang, H.L. Meng, P.G. Li, W.H. Tang, C. Cui, Effect of calcination temperature on the microstructure, crystallinity and photocatalytic activity of TiO2 hollow spheres, J. Alloys Compd., 542 (2012) 32–36.
  18. H. Zhang, J. Yang, D. Li, W. Guo, Q. Qin, L. Zhu, W. Zheng, Template-free facile preparation of monoclinic WO3 nanoplates and their high photocatalytic activities, Appl. Surf. Sci., 305 (2014) 274–280.
  19. R. Khan, M.S. Hassan, L.W. Jang, J.H. Yun, H.K. Ahn, M.S. Khil, I.H. Lee, Low-temperature synthesis of ZnO quantum dots for photocatalytic degradation of methyl orange dye under UV irradiation, Ceram. Int., 40 (2014) 14827–14831.
  20. Q. Ma, Y. Wang, J. Kong, H. Jia, Tunable synthesis, characterization and photocatalytic properties of various ZnS nanostructures, Ceram. Int., 42 (2016) 2854–2860.
  21. D. Sánchez-Martínez, I. Juárez-Ramírez, L.M. Torres-Martínez, I. De León-Abarte, Photocatalytic properties of Bi2O3 powders obtained by an ultrasound-assisted precipitation method, Ceram. Int., 42 (2016) 2013–2020.
  22. Z. Yu, B. Yin, F. Qu, X. Wu, Synthesis of self-assembled CdS nanospheres and their photocatalytic activities by photodegradation of organic dye molecules, Chem. Eng. J., 258 (2014) 203–209.
  23. C. Tian, Q. Zhang, A. Wu, M. Jiang, Z. Liang, B. Jiang, H. Fu, Cost-effective large-scale synthesis of ZnO photocatalyst with excellent performance for dye photodegradation, Chem. Commun., 48 (2012) 2858–2860.
  24. K.M. Lee, C.W. Lai, K.S. Ngai, J.C. Juan, Recent developments of zinc oxide based photocatalyst in water treatment technology: A review, Water Res., 88 (2016) 428–448.
  25. H. Osman, Z. Su, X. Ma, S. Liu, X. Liu, D. Abduwayit, Synthesis of ZnO/C nanocomposites with enhanced visible light photocatalytic activity, Ceram. Int., 42 (2016) 10237–10241.
  26. M. Pirhashemi, A. Habibi-Yangjeh, Ultrasonic-assisted preparation of plasmonic ZnO/Ag/Ag2WO4 nanocomposites with high visible-light photocatalytic performance for degradation of organic pollutants, J. Colloid Interface Sci., 491 (2017) 216–229.
  27. A. Habibi-Yangjeh, M. Shekofteh-Gohari, Novel magnetic Fe3O4/ZnO/NiWO4 nanocomposites: Enhanced visible-light photocatalytic performance through p-n heterojunctions, Sep. Purif. Technol., 184 (2017) 334–346.
  28. M. Shekofteh-Gohari, A. Habibi-Yangjeh, Fe3O4/ZnO/CoWO4 nanocomposites: Novel magnetically separable visible lightdriven photocatalysts with enhanced activity in degradation of different dye pollutants, Ceram. Int., 43 (2017) 3063–3071.
  29. B. Golzad-Nonakaran, A. Habibi-Yangjeh, Ternary ZnO/AgI/Ag2CO3 nanocomposites: Novel visible-light-driven photocatalysts with excellent activity in degradation of different water pollutants, Mater. Chem. Phys., 184 (2016) 210–221.
  30. B. Golzad-Nonakaran, A. Habibi-Yangjeh, Photosensitization of ZnO with Ag3VO4 and AgI nanoparticles: Novel ternary visible- light-driven photocatalysts with highly enhanced activity, Adv. Powder Technol., 27 (2016) 1427–1437.
  31. L. Muñoz-Fernandez, A. Sierra-Fernandez, O. Miloševiæ, M.E. Rabanal, Solvothermal synthesis of Ag/ZnO and Pt/ZnO nanocomposites and comparison of their photocatalytic behaviors on dyes degradation, Adv. Powder Technol., 27 (2016) 983–993.
  32. C. Yu, K. Yang, W. Zhou, Q. Fan, L. Wie, J.C. Yu, Preparation, characterization and photocatalytic performance of noble metals (Ag, Pd, Pt, Rh) deposited on sponge-like ZnO microcuboids, J. Phys. Chem. Solids., 74 (2013) 1714–1720.
  33. M.M. Ismail, W.Q. Cao, M.D. Humadi, Synthesis and optical properties of Au/ZnO core–shell nanorods and their photocatalytic activities, Optik., 127 (2016) 4307–4311.
  34. O. Bechambi, M. Chalbi, W. Najjar, S. Sayadi, Photocatalytic activity of ZnO doped with Ag on the degradation of endocrine disrupting under UV irradiation and the investigation of its antibacterial activity, Appl. Surf. Sci., 347 (2015) 414–420.
  35. B. Astinchap, R. Moradian, M.N. Tekyeh, Investigating the optical properties of synthesized ZnO nanostructures by solgel: The role of zinc precursors and annealing time, Optik., 127 (2016) 9871–9877.
  36. B. Liu, H.C. Zeng, Hydrothermal synthesis of ZnO nanorods in the diameter regime of 50 nm, J. Am. Chem. Soc., 125 (2003) 4430–4431.
  37. Y. Liu, M. Liu, Ordered ZnO nanorods synthesized by combustion chemical vapor deposition, J. Nanosci. Nanotechnol., 7 (2007) 4529–4533.
  38. G. Oster, M. Yamamoto, Zinc oxide sensitized photochemical reduction and oxidation, J. Phys. Chem., 70 (1966) 3033–3036.
  39. S. Akir, A. Barras, Y. Coffinier, M. Bououdina, R. Boukherroub, A.D. Omrani, Eco-friendly synthesis of ZnO nanoparticles with different morphologies and their visible light photocatalytic performance for the degradation of Rhodamine B, Ceram. Int., 42 (2016) 10259–10265.
  40. T. Tharsika, A.S.M.A. Haseeb, S.A. Akbar, M. Thanihaichelvan, Tailoring ZnO nanostructures by spray pyrolysis and thermal annealing, Ceram. Int., 41 (2015) 5205–5211.
  41. O. Carp, A. Tirsoaga, R. Ene, A. Ianculescu, R.F. Negrea, P. Chesler, G. Ionita, R. Birjega, Facile, high yield ultrasound mediated protocol for ZnO hierarchical structures synthesis: Formation mechanism, optical and photocatalytic properties, Ultrason. Sonochem., 36 (2017) 326–335.
  42. F. Solis-Pomar, A. Jaramillo, J. Lopez-Villareal, C. Medina, D. Rojas, A.C. Mera, M.F. Meléndrez, E. Pérez-Tijerina, Rapid synthesis and photocatalytic activity of ZnO nanowires obtained through microwave-assisted thermal decomposition, Ceram. Int., 42 (2016) 18045–18052.
  43. L. Duan, X. Zhao, Z. Zheng, Y. Wang, W. Geng, F. Zhang, Structural, optical and photocatalytic properties of (Mg,Al)-codoped ZnO powders prepared by sol–gelmethod, J. Phys. Chem. Solids., 76 (2015) 88–93.
  44. X. Xing, D. Deng, Y. Li, N. Chen, X. Liu, Y. Wang, Macro-nanoporous Al-doped ZnO via self-sustained decomposition of metal-organic complexes for application in degradation of Congo red, Ceram. Int., 42 (2016) 18914–18924.
  45. X. Zhang, Y. Chen, S. Zhang, C. Qiu, High photocatalytic performance of high concentration Al-doped ZnO nanoparticles, Sep. Purif. Technol., 172 (2017) 236–241.
  46. B. Czech, M. Hojamberdiev, UVA- and visible-light-driven photocatalytic activity of three-layer perovskite Dion-Jacobson phase CsBa2M3O10 (M = Ta, Nb) and oxynitride crystals in the removal of caffeine from model wastewater, J. Photochem. Photobiol., A., 324 (2016) 70–80.
  47. X. Yuan, Q. Jing, J. Chen, L. Li, Photocatalytic Cr(VI) reduction by mixed metal oxide derived from ZnAl layered double hydroxide, Appl. Clay Sci., 143 (2017) 168–174.
  48. G.P. Sahoo, S. Samanta, D.K. Bhui, S. Pyne, A. Maity, A. Misra, Hydrothermal synthesis of hexagonal ZnO microstructures in HPMC polymer matrix and their catalytic activities, J. Mol. Liq., 212 (2015) 665–670.
  49. F.M. Stringhini, E.L. Foletto, D. Sallet, D.A. Bertuol, O. Chiavone- Filho, C.A. Oller do Nascimento, Synthesis of porous zinc aluminate spinel (ZnAl2O4) by metal-chitosan complexation method, J. Alloys Compd., 588 (2014) 305–309.
  50. H.R. Liu, Y.J. Wei, Y.C. Hu, W. Jia, H. Ma, H.S. Jia, Effects of Ag nanoparticles on morphology and photocatalytic activities of GaN microrods arrays, Mater. Lett., 134 (2014) 119–122.
  51. A.A.A. Ahmed, A.T. Zainal, Z.H. Mohd, Z. Azmi, Improvement of the crystallinity and photocatalytic property of zinc oxide as calcination product of Zn–Al layered double hydroxide, J. Alloys Compd., 539 (2012) 154–160.
  52. S. Li, Z. Bai, D. Zhao, Characterization and friction performance of Zn/Mg/Al-CO3 layered double hydroxides, Appl. Surf. Sci., 284 (2013) 7–12.
  53. Y. Guo, Z. Zhu, Y. Qiu, J. Zha, Adsorption of arsenate on Cu/ Mg/Fe/La layered double hydroxide from aqueous solutions, J. Hazard. Mater., 239–240 (2012) 279–288.
  54. L. Zhang, C. Dai, X. Zhang, Y. Liu, J. Yan, Synthesis and highly efficient photocatalytic activity of mixed oxides derived from ZnNiAl layered double hydroxides, Trans. Nonferrous Met. Soc. China., 26 (2016) 2380−2389.
  55. Y. Yang, H. Li, F. Hou, J. Hu, X. Zhang, Y. Wang, Facile synthesis of ZnO/Ag nanocomposites with enhanced photocatalytic properties under visible light, Mater. Lett., 180 (2016) 97–100.
  56. S. Qourzal, N. Barka, M. Tamimi, A. Assabbane, A. Nounah, A. Ihlal, Y. Ait-Ichou, Sol–gel synthesis of TiO2–SiO2 photocatalyst for β-naphtholphotodegradation, Mater. Sci. Eng., C. 29 (2009) 1616–1620.
  57. I.K. Konstantinou, T.A. Albanis, TiO2-assisted photocatalytic degradation of azo dyes in aqueous solution: kinetic and mechanistic investigations: a review, Appl. Catal. B Environ., 49 (2004) 1–14.
  58. N. Daneshvar, D. Salari, A.R. Khataee, Photocatalytic degradation of azo dye acid red 14 in water on ZnO as an alternative catalyst to TiO2, J. Photochem. Photobiol. A Chem., 162 (2004) 317–322.
  59. A.A. Khodja, T. Sehili, J.F. Pilichowski, P. Boule, Photocatalytic degradation of 2-phenylphenol on TiO2 and ZnO in aqueous suspensions, J. Photochem. Photobiol. A Chem., 141 (2001) 231– 239.
  60. N. Barka, S. Qourzal, A. Assabbane, A. Nounah, Y. Ait-Ichou, Photocatalytic degradation of an azo reactive dye, Reactive Yellow 84, in water using an industrial titanium dioxide coated media, Arab. J. Chem., 3 (2010) 279–283.
  61. J. Fang, H. Fan, Y. Ma, Z. Wang, Q. Chang, Surface defects control for ZnO nanorods synthesized by quenching and their anti-recombination in photocatalysis, Appl. Surf. Sci., 332 (2015) 47–54.