Visible-Light-Driven Nitrogen-Doped Carbon Quantum Dots/CaTiO₃ Composite Catalyst with Enhanced NO Adsorption for NO Removal

Abstract

Nitrogen oxides (NO x ) have attracted extensive concerns as a secondary aerosol precursor in recent years. Solar-induced photocatalytic oxidation is a promising strategy for of NO x removal nowadays. In this contribution, nitrogen-doped carbon quantum dots (N-CQDs)/CaTiO3 composite was synthesized using a facile hydrothermal process. The incorporation of N-CQDs to CaTiO3 facilitates the transfer of electrons and divorce of photogenerated carriers. NO temperature-programmed desorption (NO-TPD) demonstrated that the presence of N-CQDs was conducive to the NO adsorption in comparison with the pristine CaTiO3. The composite catalyst demonstrated much better photocatalytic performance than CaTiO3 and P25 did in regard to gaseous NO removal and NO2 selectivity under visible light irradiation. Both •O2 – and •OH are believed to make a major contribution to NO removal. The role of N-CQDs was unraveled in the photocatalytic reaction of NO elimination over N-CQDs/CaTiO3 samples. This study provides insight into the composite catalyst N-CQDs/CaTiO3 in photocatalytic reactions and applications.

Vanadium doped CaTiO3 cuboids: role of vanadium in improving the photocatalytic activity

“…Various dopants such as Ag, Cr, Cu, Er, Eu, Fe, La, N, Na, Zr have been utilized to improve the photocatalytic efficiency of CaTiO3. 24,[27][28][29][30][31][32][33][34] In addition to this, co-doping has been utilized in order to passivate the unoccupied impurity states induced by mono-doped systems and thus suppress the recombination rate of photoinduced charges. 24,27,28 Recently we reported vanadium to be a promising dopant in SrTiO3 and BaTiO3 for photocatalytic degradation of MB and thermoelectric applications, and found that the site occupancy of dopant decides the efficiency of the material.…”

One-Pot Fabrication of Hierarchical Floating Bi–Bi2S3–Bi2WO6/Expanded Perlite Photocatalysts for Efficient Photocatalysis of Organic Contaminants Utilized Sunlike Illumination

“…To further inspect the presence of hydroxyl ( • OH) and superoxide (O 2 •– ) radicals which are photoinduced during the degradation reaction, electron paramagnetic resonance (EPR) tests were performed. The reagent 5,5-dimethyl-1-pyrroline- N -oxide (DMPO) was applied in aqueous and methanolic suspensions , for inspections of • OH and O 2 •– radicals (Figure b) utilizing visible light, respectively. Hence, scavenger trapping experiments confirmed by EPR testing proved evidently that • OH and O 2 •– radicals are the foremost photogenerated species during photocatalytic decomposition of stable organic pollutants.…”

“…•− ) radicals which are photoinduced during the degradation reaction, electron paramagnetic resonance (EPR) tests were performed. The reagent 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) was applied in aqueous and methanolic suspensions 65,66 for inspections of • OH and O 2…”

N, S doped carbon quantum dots inside mesoporous silica for effective adsorption of methylene blue dye

“…They also can easily functionalize their surface in order to improve their selectivity [15,16]. Lately, CQDs modified semiconductor materials have been studied for various photocatalytic and electrical applications, for example, CQDs/BiOI [17], CQDs/ZnFe 2 O 4 [18], and CQDs/CaTiO 3 [19] nanocomposites. The photodegradation of volatile organic compounds using CQDs/TiO 2 has been rarely studied [20].…”