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In this work, a combinatorial methodology was developed for photodegradation catalyst screening. A fluorescence imaging detection system was designed for high throughput analysis, 1,6-hexamethylenediamine was used as the probe molecule for catalyst testing. The photodegradation activity of catalysts was evaluated by 1,6-hexamethylenediamine consumption during the photodegradation reaction. The methodology could provide reliable results. We found that pure TiO 2 , ZrO 2 , Nb 2 O 5 , MoO 3 , and WO 3 did not show much activity for 1,6-hexamethylenediamine photodegradation under visible light. TiO 2 catalysts doped with different metal ions were tested. When TiO 2 was doped with Ta 2 O 5 , Nb 2 O 5 , V 2 O 5 , MoO 3 , or WO 3 , higher activity for photodegradation was observed. The doping of La 3+ , Ba 2+ , and Br − to TiO 2 did not improve the catalytic activities. When doping TiO 2 with Mn 2+ , Cl − , Al 3+ , Cu 2+ , Fe 3+ , Na + , Mg 2+ , Li + , F − , Co 2+ , or K + , catalytic activity was lower than that of pure TiO 2 . After elaborate catalysts screening, we discovered new catalysts, such as 50–70% TiO 2 /0–20% WO 3 /20–40% VO 2.5 and 20–30% TiO 2 /30–50% MoO 3 /40–60% VO 2.5 as well as 30% WO 3 /20% ZrO 2 /50% NbO 2.5 (synthesized from ZrCl 4 , NbCl 5 , and (NH 4 ) 5 H 5 [H 2 (WO 4 ) 6 ]·H 2 O in ethanol solution or suspension) and 60–70% WO 3 /Nb 2 O 5 (synthesized from WCl 6 and NbCl 5 in ethanol solution). We observed that the catalytic activity is sensitive to preparation methods and catalyst specific surface areas. When P123 (HO(CH 2 CH 2 O) 20 (CH 2 CH(CH 3 )O) 70 (CH 2 CH 2 O) 20 H, designated EO 20 PO 70 EO 20 ) was used as template to synthesize mesoporous materials, the mesoporous catalysts showed higher activity than regular catalytic materials. |
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