Environmental Engineering Unit, College of Engineering, University of the Philippines, Diliman, Quezon City, 1101, Philippines; Research and Development Division, Environmental Management Bureau, Department of Environment and Natural Resources, Quezon City, 1101, Philippines.
Department of Chemical Engineering, University of the Philippines, Diliman, Quezon City, 1101, Philippines.
Chemosphere. 2017 Sep;182:174-182. doi: 10.1016/j.chemosphere.2017.05.022. Epub 2017 May 5.
This study developed a modified titanium dioxide photocatalyst doped with multi-element synthesized via sol-gel process to productize a novel photocatalyst. The study includes degradation of gaseous formaldehyde under visible light using the synthesized novel titanium dioxide photocatalyst. Varying molar ratios from 0 to 2 percent (% in titanium dioxide) of ammonium fluoride, silver nitrate and sodium tungstate as dopant precursors for nitrogen, fluorine, silver and tungsten were used. Photodegradation of gaseous formaldehyde was examined on glass tubular reactors illuminated with blue light emitting diodes (LEDs) using immobilized photocatalyst. The photocatalytic yield is analyzed based on the photocatalyst surface chemical properties via X-ray Photoelectron Spectroscopy (XPS), Fourier Transform Infrared (FTIR) Spectrophotometry, Brunauer-Emmett-Teller (BET) and X-ray Diffraction (XRD) characterization results. The applied modifications enhanced the visible light capability of the catalyst in comparison to the undoped catalyst and commercially available Degussa P-25, such that it photocatalytically degrades 88.1% of formaldehyde in 120 min. Synthesized titanium dioxide photocatalyst exhibits a unique spin orbital at 532.07 eV and 533.27 eV that came from the hybridization of unoccupied Ti d(t) levels.
本研究通过溶胶-凝胶工艺合成了一种新型的掺杂多元素的改良二氧化钛光催化剂，实现了该光催化剂的产业化。本研究包括利用合成的新型二氧化钛光催化剂在可见光下降解气态甲醛。使用不同摩尔比（二氧化钛中 0 至 2%）的氟化铵、硝酸银和钨酸钠作为氮、氟、银和钨的掺杂前体，对其进行了研究。采用固定化光催化剂，在蓝色发光二极管（LED）照射的玻璃管式反应器中对气态甲醛的光降解进行了考察。通过 X 射线光电子能谱（XPS）、傅里叶变换红外（FTIR）分光光度法、BET 和 X 射线衍射（XRD）等表面化学性质分析，对光催化性能进行了分析。与未掺杂的催化剂和市售 Degussa P-25 相比，所应用的修饰提高了催化剂对可见光的利用能力，使得催化剂在 120 分钟内光催化降解了 88.1%的甲醛。合成的二氧化钛光催化剂在 532.07 eV 和 533.27 eV 处表现出独特的自旋轨道，这是由未占据的 Ti d(t) 能级杂化引起的。
