Highly Efficient Solar Light Driven g-C₃N₄@Cs_0.33WO₃ Heterojunction for the Photodegradation of Colorless Antibiotics

Abstract

This study facilitates the synthesis of a graphitic carbon nitride/cesium tungsten oxide (g-C3N4@Cs0.33WO3) heterojunction using a solvothermal method. The photocatalytic activities of the prepared samples were examined for the photodegradation of colorless antibiotics, namely tetracycline, enrofloxacin, and ciprofloxacin, as well as cationic and anionic dyes, such as methyl orange, rhodamine B, neutral red, and methylene blue, under full-spectrum solar light. We have purposely selected different kinds of wastewater pollutants of colorless antibiotics and cationic and anionic organic dyes to investigate the potential application of this heterojunction toward different groups of water pollutants. The results revealed that the g-C3N4@Cs0.33WO3 heterojunction showed an outstanding photocatalytic activity toward all the pollutants with concentrations of 20 ppm each at pH 3 by photocatalytically removing 97% of tetracycline within 3 h, 98% of enrofloxacin within 2 h, 97% of ciprofloxacin within 2.25 h, 98% of methylene blue in 1 h, 99% of rhodamine B within 2 h, 99% of neutral red in 1.25 h, and 95% of methyl orange in 2 h. These findings indicate that the developed photocatalyst possesses excellent photocatalytic properties toward seven different water pollutants that make it a universal photocatalyst. The developed g-C3N4@Cs0.33WO3 oxide heterojunction also presented a photocatalytic performance better than those of reported solar light active photocatalysts for photodegradation of rhodamine B and tetracycline. The efficient photocatalytic performance of the heterojunction can be ascribed to its extended light-absorbing ability, effective charge separation and fast charge transfer properties, and a high surface area. Moreover, an active species detection experiment also confirmed that superoxide radicals, hydroxyl radicals, and holes played significant roles in the photocatalysis of the organic dyes and tetracycline.

Recent advances in removal of pharmaceutical pollutants in wastewater using metal oxides and carbonaceous materials as photocatalysts: a review

“…The presence of ciprofloxacin in water acts as pollutant and can be removed by means of a photocatalytic approach. 425–524…”

“…Z-Scheme-guided g-C 3 N 4 /Bi 2 WO 6 , 513 Fe 3 O 4 /Bi 2 WO 6 , 514 g-C 3 N 4 /Ti 3 C 2 /MXene/black phosphorus, 515 g-C 3 N 4 /Ag 3 PO 4 /chitosan, 516 Ag/AgVO 3 /g-C 3 N 4 , 517 CeO 2 /Co 3 O 4 p–n hetrojunctions, 518 Bi nanodots/2D Bi 3 NbO 7 nanosheets, 519 Bi 2 WO 6 /Ta 3 N 5 , 520 g-C 3 N 4 @Cs 0.33 WO 3 , 521 ZnO/SnS 2 , 522 g-C 3 N 4 /rGO/WO 3 , 523 and CuS/BiVO 4 524 have also displayed enhanced photocatalytic degradation of ciprofloxacin.…”

Simultaneous elimination of toxic dyes, ciprofloxacin and Cr(vi) contents from polluted water: escalating surface plasmon electrons of Ag cocatalysts on BiVO4 microstructures

“…A straight line shows that the degradation of dyes and organic pollutants follows the first order kinetics. 67 The photoreaction process for CR and CV is illustrated in Fig. 8d.…”

Novel solar-light-driven Z-scheme BiOCl@WS2 nanocomposite photocatalysts for the photocatalytic removal of organic pollutants

“…[1][2][3][4][5][6][7][8][9] Among the renewable energy sources, solar energy is most suitable and efficient to overcome the global energy deficiency and mitigate environmental degradation owing to its various merits, such as abundance, low cost, ecofriendliness, and accessibility. [10][11][12][13][14][15][16][17][18] Nowadays, it is being applied in various areas of environmental remediation and energy generation, such as the degradation of hazardous organic pollutants, [19][20][21][22] CO 2 reduction, 23 H 2 generation, 2,24 heavy metal treatment, 25 water evaporation, 13,26,27 and pyroelectric energy harvesting. 28 Among these areas, the photocatalytic degradation of persistent organic pollutants has received a lot of attention owing to their low biodegradability and harmful effects on the environment.…”

“…28 Among these areas, the photocatalytic degradation of persistent organic pollutants has received a lot of attention owing to their low biodegradability and harmful effects on the environment. 19,22,29,30 To date, different photocatalysts have been developed for the treatment of these organic pollutants. However, there is still a huge gap in their practical applications due to one or more of the following reasons: high cost, low irradiated solar light utilization, poor chemical stability, fast recombination of electrons and holes, bad cyclic stability, and difficulty of separation.…”