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The photo-induced peroxymonosulfate (photo-PMS) reaction is a promising route to eliminate antibiotics from waste water. To achieve excellent photo-PMS activity in Mg–Fe layered double hydroxides (LDHs) for tetracycline hydrochloride (TCH) degradation under simulative solar-light irradiation, Mg–Fe LDHs-loaded polyacrylonitrile (Mg–Fe/PAN) nanofibers were in-situ prepared via the hydrothermal route. For comparison to the photocatalysis and photo-PMS process, the Mg–Fe/PAN-assisted photo-PMS process exhibited a better elimination activity for TCH elimination. In addition, the photo-PMS activities of Mg–Fe/PAN composites were greatly affected by Mg–Fe LDHs content, TCH concentration, pH, and inorganic salts. Among these Mg–Fe/PAN composites, the optimal MgFe2/PAN with a Mg/Fe molar ratio of 1:2 and a nominal Mg–Fe LDHs content of 2.0 wt. % removed 81.31% TCH solution of 80 mg L−1 TCH within 120 min. This enhanced photo-PMS capacity of MgFe2/PAN was ascribed to the abundant active sites formed by functional groups and oxygen defects for efficient TCH species adsorption and photon capturing, and the tight interface between Mg–Fe LDHs nanoparticles and PAN nanofibers for the rapid separation and transfer of photoinduced e−/h+ pairs. SO4•− and •O2− radicals were vital for the MgFe2/PAN-assisted photo-PMS reaction. [ABSTRACT FROM AUTHOR]

To disclose the effect of crystal plane on the adsorption-photocatalytic activity of MnS, octahedral MnS was prepared via the hydrothermal route to enhance the adsorption and photocatalytic efficiencies of tetracycline hydrochloride (TCH) in visible light region. The optimal MnS treated at 433 K for 16 h could remove 94.83% TCH solution of 260 mg L−1 within 180 min, and its adsorption-photocatalytic efficiency declined to 89.68% after five cycles. Its excellent adsorption-photocatalytic activity and durability were ascribed to the sufficient vacant sites of octahedral structure for TCH adsorption and the feasible band-gap structure for visible-light response. In addition, the band gap structure (1.37 eV) of MnS with a conduction band value of −0.58 eV and a valence band value of 0.79 eV was favorable for the generation of O2−, while unsuitable for the formation of OH. Hence, octahedral MnS was a potential material for the removal of antibiotics from wastewater. [ABSTRACT FROM AUTHOR]

Photocatalysis is a promising route to convert solar light into chemical energy for H 2 evolution and pollutants degradation. Hence, Ni 2 P decorated ZnCr 2 O 4 (Ni 2 P/ZnCr 2 O 4) nanofibers were prepared for boosting solar-light induced water splitting and tetracycline hydrochloride (TCH) degradation. For comparison to ZnCr 2 O 4 nanofibers, Ni 2 P/ZnCr 2 O 4 composites exhibited the better photocatalytic activities for water splitting and TCH removal. Owing to the co-catalytic effect of Ni 2 P for the efficient photon capture, the charge carriers were rapidly separated and migrated at the interface between Ni 2 P and oxygen-defected ZnCr 2 O 4. H 2 evolution rate of optimal C–Ni 2 P/ZnCr 2 O 4 with a nominal Ni 2 P content of 9.0 wt% was 575.89 μmol g−1 h−1, and its apparent quantum yield at 420 nm was 15.25 %, while its H 2 evolution decreased from 2815.13 to 2602.51 μmol g−1 after fifth cycle. In addition, the removal efficiency of C–Ni 2 P/ZnCr 2 O 4 was 93.68 % within 90 min, and declined to 88.76 % after five cycles for solar-light driven degradation of 50 mg L−1 TCH solution. The deactivation of C–Ni 2 P/ZnCr 2 O 4 was due to the photo-corrosion for the change in valence states of compositions. [ABSTRACT FROM AUTHOR]

S-defected In 2 S 3 /ZnS nanospheres were synthesized via a microwave-assisted hydrothermal route for facilitating the solar-light induced photodegradation of tetracycline hydrochloride (TCH). The removal efficiency of TCH over In 2 S 3 /ZnS was higher in comparison to pure ZnS and In 2 S 3. The adsorption-photocatalytic capacity of S-defected In 2 S 3 /ZnS was affected by In 2 S 3 content, TCH concentration, inorganic salts, pH, and quenchers. The removal efficiency of optimal 3-In 2 S 3 /ZnS for TCH solution of 50 mg L−1 was 100% within 90 min, and decreased to 93.26% after five cycle times. The main active species were •O 2 - and h+ in solar-light driven photocatalytic system. The enhanced photocatalytic performance of S-defected In 2 S 3 /ZnS was due to the tight interface between In 2 S 3 and ZnS for the efficient transfer and utilization of photo-induced carriers. [Display omitted] • In 2 S 3 /ZnS nanospheres were prepared by a microwave-assisted hydrothermal route. • Tight interface of In 2 S 3 and ZnS favored the transfer and utilization of charge carriers. • S-defected In 2 S 3 /ZnS exhibited the excellent photocatalytic activity and durability. [ABSTRACT FROM AUTHOR]

To overcome the poor visible-light harvesting and the inferior charge transfer and separation of MgO, MgO nanosheets were co-modified by S and FeS (FeS/S-MgO) via a high-temperature sulfurized route. Compared with pure S-MgO, FeS/S-MgO exhibited higher photocatalytic capacity for tetracycline hydrochloride (TCH) under solar light irradiation. It's attributed to the junction interface between FeS and O-defected S-MgO for promoting the transfer and separation of photo-induced carriers and enhancing the visible-light absorption capacity. The photocatalytic activity of FeS/S-MgO was greatly affected by FeS content, TCH concentration, pH, inorganic salts, and quenchers. The optical 3-FeS/S-MgO with a FeS content of 7.94 wt% degrade 97.10% TCH solution of 40 mg L−1, and declined to 94.21% after five cycles under the same conditions. •OH and h+ played the crucial role in 3-FeS/S-MgO assisted photocatalytic system. [Display omitted] • FeS/S-MgO composites were prepared by high-temperature sulfurization. • FeS/S-MgO enhanced the visible-light harvesting and the charge transfer. • •OH and h+ played the vital role in solar-light driven degradation of TCH. [ABSTRACT FROM AUTHOR]

To enhance the adsorption-photocatalytic capacity of tetracycline hydrochloride (TCH) under solar light irradiation, ultrafine CuInS 2 nanoparticles of 5 nm modified MgO with S doping (CIS/S-MgO) nanosheets were in-situ sulfurized in the nonthermal plasma. Compared with pure MgO, In 2 S 3 /S-MgO and CuS/S-MgO, CIS/S-MgO exhibited the better photocatalytic activity while worse adsorption capacity. The optimal 2-CIS/S-MgO could remove 98.4% of 200 mg L−1 TCH solution within 180 min, and declined to 92.3% after five cycles. The attenuated surface discharge and small BET surface area of CIS/S-MgO induced to the inferior adsorption capacity, while the Z-structured junction formed between CuInS 2 and S-MgO was favorable for the charge transfer and separation of electron-hole pairs. •O 2 − was vital for enhancing the solar-light photocatalytic activity of 2-CIS/S-MgO. [Display omitted] • CIS/S-MgO nanosheets were in-situ sulfurized in the nonthermal plasma. • Optimal CIS/S-MgO removed 98.4% of 200 mg L−1 TCH solution within 180 min. • O 2 - was the vital radical in adsorption-photocatalytic system. • Z-structured junction favored the transfer and separation of charge carriers. [ABSTRACT FROM AUTHOR]

In recent years, photocatalysis has been confirmed as an emerging route to eliminate the contaminants such as dyes, antibiotics, and heavy metals from wastewater. To explore MoO 3 -based photocatalyst with excellent photocatalytic activity, BiVO 4 -modified hexagonal h-MoO 3 (BiVO 4 /MoO 3) composites were constructed for solar-light induced photodegradation of tetracycline hydrochloride (TCH) via a chemical precipitation approach. Compared with pure h-MoO 3 , BiVO 4 /MoO 3 exhibited the inferior adsorption capacity while efficient photocatalytic activity. The removal efficiency of TCH over BiVO 4 /MoO 3 was affected by BiVO 4 content, pH, and inorganic ions. For optimal 3-BiVO 4 /MoO 3 with a BiVO 4 content of 4.25%, the adsorption-photocatalytic efficiency of 190 mg L−1 TCH was 97.66% within 160 min, and decreased to 91.35% after five cycles under the same conditions. The quenching experiments indicated that h+ and·O 2 - served as the main species in adsorption-photocatalytic system. The tight junction interface between BiVO 4 and MoO 3 could enhance the visible-light response and the transfer and separation of photoinduced electron-hole pairs. Hence, the excellent activity and durability of BiVO 4 /MoO 3 was favorable for the adsorption-photodegradation of organic pollutants. [Display omitted] • BiVO 4 /MoO 3 enhanced the solar-light photodegradation efficiency of TCH. • h+ and ·O 2 - served as the main species in adsorption-photocatalytic system. • BiVO 4 /MoO 3 promoted the separation and migration of charge carriers. [ABSTRACT FROM AUTHOR]

LaFeO 3 /MgFe 2 O 4 heterojunctions were prepared via the sol-gel route to enhance solar-light induced photo-persulfate degradation of tetracycline hydrochloride (TCH). LaFeO 3 /MgFe 2 O 4 exhibited the better removal efficiency of TCH in comparison to LaFeO 3 and MgFe 2 O 4. The photo-persulfate activity of LaFeO 3 /MgFe 2 O 4 was intensively affected by LaFeO 3 content, pH, and inorganic salts. Under the optimal conditions, 2-LaFeO 3 /MgFe 2 O 4 with a nominal LaFeO 3 content of 10 wt % presented the removal efficiency of 97.01 %, while declined to 85.40 % after ninth-cycle test. The lattice defects formed in LaFeO 3 and MgFe 2 O 4 acted as the active sites for TCH adsorption and photon capture. The oxygen-defected tight interface between LaFeO 3 and MgFe 2 O 4 was favorable for the separation and migration of photo-induce e-/h+ pairs, boosting solar-light response for photo-persulfate activity of LaFeO 3 /MgFe 2 O 4. However, the long-term photo-corrosion inevitably induced to the change in valance states of surface compositions, weakening the photo-persulfate performance in TCH elimination. [Display omitted] • LaFeO 3 /MgFe 2 O 4 hybrids were prepared via the sol-gel approach. • LaFeO 3 /MgFe 2 O 4 had the strong solar-light photo-persulfate activity for TCH degradation. • The tight interface favored the transfer and migration of photo-induced e-/h+ pairs. • Photo-induced radicals and Fe2+/Fe3+ couples promoted the persulfate oxidation. [ABSTRACT FROM AUTHOR]

Metal oxides-based heterojunction fabrication is a promising strategy to eliminate antibiotics from wastewater via adsorption-photocatalysis. ZnLa x Bi 2−x O 4 hybrids with various La/Bi molar ratios were fabricated for enhancing the adsorption-photocatalytic elimination of tetracycline hydrochloride (TCH). Oxygen-defected ZnLa x Bi 2−x O 4 composites provided the sufficient sites for photon capture and pollutants adsorption. In addition, the tight p-n-p type interface among oxygen-defected La 2 O 3 , ZnO, and spinel ZnBi 2 O 4 favored the rapid transfer and migration of photo-excited e-/h+ pairs, enlarging the visible light utilization. Hence, ZnLa x Bi 2−x O 4 samples had the better adsorption-photocatalytic activity than ZnLa 2 O 4 and ZnBi 2 O 4 for TCH removal. Langmuir and second-order models well described the adsorption isotherms and kinetics of ZnLa x Bi 2−x O 4 samples, respectively. The adsorption capacity of optimal ZnLa 1.75 Bi 0.25 O 4 with a La/Bi molar ratio of 7:1 was 406.85 mg g−1, and its removal efficiency of 210 mg L−1 TCH solution was 98.04 % within 150 min. The change in valence states of surface compositions induced to the declined removal efficiency of ZnLa 1.75 Bi 0.25 O 4 to 91.95 % after five cycle times. [Display omitted] • ZnLa x Bi 2−x O 4 heterojunctions had the excellent adsorption-photocatalytic activities. • The adsorption capacity of optimal of ZnLa 1.75 Bi 0.25 O 4 was 406.85 mg g−1. • The removal efficiency of 210 mg L−1 TCH solution over ZnLa 1.75 Bi 0.25 O 4 was 98.05 %. • Langmuir and second-order models well fitted with the adsorption behaviors of ZnLa x Bi 2−x O 4. [ABSTRACT FROM AUTHOR]

Heterojunctions constructed from metal organic frameworks (MOF) and metal sulfides are the potential candidates for solar-light driven photo-Fenton elimination of antibiotics from wastewater. To boost the solar-light induced photo-Fenton degradation of tetracycline hydrochloride (TCH) over UiO-66, NH 2 -functionlized UiO-66 (UiO-66-NH 2) was in-situ loaded with NiS (NiS/NU-66) via the nonthermal plasma sulfurization. For comparison to UiO-66-NH 2 , NiS/NU-66 had the lower adsorption capacity while the higher photo-Fenton activity for TCH removal. The removal efficiency of NiS/NU-66 climbed and then declined with an increase in NiS content, and the best removal efficiency (84.92 ± 2.55 %) for 110 mg L−1 TCH solution was obtained by c-NiS/NU-66 in 150 min. The sulfur and oxygen defects as well as the plentiful functional groups over NiS/NU-66 were favorable for providing the abundant vacant sites of TCH adsorption and photons capture. In addition, the rapid separation and migration of photo-generated e−/h+ pairs were achieved at the tight junction interface between NiS and UiO-66-NH 2 , enlarging the visible-light absorption capacity. In NiS/NU-66-assisted photocatalytic system, H 2 O 2 was efficiently convert to •OH by e− and Ni2+/Ni3+ couples in solar light region. Hence, •OH, •O 2 − and h+ played the vital roles in this photo-Fenton system. [Display omitted] • NiS/UiO-66-NH 2 was fabricated by the in-situ nonthermal plasma sulfurization. • Lattice defects and functional groups favored the adsorption and photo-Fenton reaction. • NiS/UiO-66-NH 2 enhanced the photo-Fenton activity while reduced the adsorption capacity. [ABSTRACT FROM AUTHOR]

To extend the efficiency of biochar in the adsorption-photocatalytic removal of tetracycline hydrochloride from wastewater, biochar derived from bagasse were co-modified with La 2 S 3 and MgO (La/Mg-biochar) via the one-pot high-temperature sulfidation. Compared to MgO/biochar and La 2 S 3 /biochar, La/Mg-biochar composites exhibited higher adsorption-photocatalysis activity for tetracycline hydrochloride (TCH) removal at a low optical density (25 mW cm-2). The functional groups, O-H, C-N, C-O and Mg-O etc, in La/Mg-biochar provided the abundant vacant sites for TCH adsorption and photocatalysis, and the junction interface among La 2 S 3 , MgO, and biochar was likely to form the channels for the separation and transfer of photo-induced e-/h+ pairs. La/Mg-biochar present the better adsorption-photocatalytic capacity of TCH than La 2 S 3 and MgO modified biochar. The adsorption process of La/Mg-biochar was spontaneous physical adsorption, which was well described by second-order and Langmuir models. The optimal 2-La/b-Mg-biochar could remove 95.01% removal of 100 mg L-1 TCH solution within 120 min, and its adsorption capacity was 120.59 mg g-1. Biochar-based composites thus display a high potential application in the removal of antibiotic pollutants from wastewater. • Biochar was co-modified by La 2 S 3 and MgO via one-pot sulfidation. • Optimal 2-La/b-Mg-biochar removed 95.01% TCH solution within 120 min. • Second-order model and Langmuir well fitted with the adsorption kinetics and isotherm of La/Mg-biochar composites, respectively. • Adsorption capacity of 2-La/b-Mg-biochar based on second-order model was 120.59 mg g-1. [ABSTRACT FROM AUTHOR]

BiOCl 0.5 X 0.5 (X = F, Br, and I) heterojunctions were prepared via the solvothermal approach to achieve the solar-light induced photodegradation of tetracycline hydrochloride (TCH). The photocatalytic activity of BiOCl coupling with BiOI is greatly affected by the molar ratio of Cl/I. The best photocatalytic efficiency of 97.9 % within 120 min is obtained by flower-like BiOCl 0.5 I 0.5 microspheres with a Cl/I molar ratio of 1:1, and the removal efficiency of TCH over BiOCl 0.5 I 0.5 declines to 93.2 % after five cycles. Compared with BiOCl 0.5 Br 0.5 and BiOCl 0.5 F 0.5 , BiOCl 0.5 I 0.5 presents the better photocatalytic activity. Z-scheme junction between BiOCl and BiOI is favorable for the efficient separation and migration of photo-generated charge carriers, and the narrow band-gap structure of BiOCl 0.5 I 0.5 microspheres favors the visible-light harvesting.·O 2 - plays a vital role in BiOCl 0.5 I 0.5 -assisted photocatalytic reaction. However, the change in valance states induced by photo-corrosion is responsible for the solar-light deactivation of BiOCl 0.5 I 0.5. [Display omitted] • BiOCl 0.5 X 0.5 (X = F, Br, and I) heterojunctions have excellent photodegradation activity. • Z-scheme BiOCl 0.5 I 0.5 junction favors the rapid transfer and separation of charge carriers. • BiOCl 0.5 I 0.5 (2.09 eV) has narrow band-gap structure for visible-light harvesting. [ABSTRACT FROM AUTHOR]

[Display omitted] • B,N-codpoed biochar was modified by ZnFe 2 O 4 via the microwave-assisted pyrolysis. • ZnFe/BN-biochar exhibited excellent adsorption-photocatalytic capacity for TCH. • ZnFe/BN-biochar presented superior adsorption-photocatalytic durability for TCH. • Adsorption of TCH over ZnFe/BN-biochar was a spontaneous and physisorption process. B, N-codoped biochar was modified by ZnFe 2 O 4 (ZnFe/BN-biochar) via the one-pot microwave-assisted pyrolysis for enhancing the adsorption-photocatalytic elimination of tetracycline hydrochloride (TCH). The addition of ZnFe 2 O 4 could enhance the adsorption and photocatalytic capacity of B,N-codoped carbon under solar light irradiation. Among these composites, the optimal 3-ZnFe/3b-BN-biochar could remove 98.19 % of 150 mg L−1 TCH solution within 120 min, and its adsorption capacity estimated by Langmuir was 244.34 mg g−1 for TCH removal. However, the removal efficiency of TCH over 3-ZnFe/3b-BN-biochar decreased to 89.45 % after seven cycles. The photocatalytic and adsorption kinetics of biochar-based composites for TCH removal were well descried with Langmuir-Hinshelwood and second-order models, respectively. In addition, Langmuir well fitted with the adsorption isotherms of biochar-based composites. The adsorption process of TCH over 3-ZnFe/3b-BN-biochar was a spontaneous and physisorption process. Hence, 3-ZnFe/3b-BN-biochar was a promising material for the adsorption and photocatalytic elimination of pollutants in wastewater. [ABSTRACT FROM AUTHOR]