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Various semiconductor powders (such as bismuth oxybromide/bismuth oxyiodide (BiOBr/BiOI) nanojunctions) can photodegrade wastewater efficiently, but their practical application is limited by poor recovery performance. To address the problem, we report the construction of BiOBr/BiOI nanojunctions on flexible carbon fiber cloth (CFC) substrate as an easily recycled photocatalyst by the dipping-solvothermal-dipping-solvothermal four-step method. CFC/BiOBr/BiOI is composed of CFC substate and two layers of nanosheets, while BiOBr nanosheets (thickness: 10–30 nm, diameter: 200–400 nm) were grown in the inner layer and BiOI nanosheets (thickness: 50–80 nm, diameter:300–600 nm) were grown in the outer layer. CFC/BiOBr/BiOI (4 × 4 cm2) can effectively photodegrade 97.7% acid orange 7 (AO7), 91.3% levofloxacin (LVFX) and 97.8% tetracycline (TC) within 120 min under the illumination of visible-light, better than CFC/BiOBr (73.2% AO7, 71.6% LVFX and 81.6% TC). Furthermore, superoxide radical (•O2−) and hydroxyl radical (•OH) are the main active substances during removing LVFX by CFC/BiOBr/BiOI. Besides, CFC/BiOBr/BiOI can efficiently reduce 93.5% chemical oxygen demand (COD) concentration of acrylic resin production wastewater (ARPW) under visible-light illumination for 3 h, better than CFC/BiOBr (36.6% COD). Therefore, CFC/BiOBr/BiOI has broad application prospects in purifying wastewater as a new type of easily recycled photocatalyst.

The development of recyclable photocatalyst with high adsorption and excellent photocatalytic performance has attracted considerable attention. Herein, we report a three-component photocatalyst by constructing porous amine functionalized zirconium metal organic framework (UiO-66-NH2) and broad photo-responsive AgI on flexible carbon fiber cloth (CFC). UiO-66-NH2 nanoparticles (200–400 nm) were in-situ grown on the surface of CFC (16.5 ± 0.5 μm, 4 × 4 cm2) by a solvothermal route, then AgI particles (50–100 nm) were synthesized on CFC/UiO-66-NH2 via a modified chemical bath deposition method. The obtained CFC/UiO-66-NH2/AgI can effectively adsorb 19.0% levofloxacin (LVFX) or 18.4% ciprofloxacin (CIP) in 60 min in the dark and degrade 84.5% LVFX or 79.6% CIP in 120 min under visible light irradiation. Furthermore, the filter-membrane-shaped CFC/UiO-66-NH2/AgI can be utilized to treat the flowing sewage (CIP, 10 mg/L, ~1 L/h), and the removing efficiency of CIP reached 71.0% after 10 grades. Therefore, this work demonstrates the huge application prospect of recyclable CFC/UiO-66-NH2/AgI with high adsorption and photocatalytic capacity in flowing sewage treatment under visible light illumination.

Numerous nanosized photocatalysts have been demonstrated to treat antibiotic solutions efficiently in beakers, but plenty of antibiotics have been discharged to the flowing rivers. For photocatalytically degrading the flowing antibiotic wastewater, the prerequisite is to develop flexible large-scale filter-membrane with high photocatalytic activity. To solve this issue, with carbon fiber (CF) cloth as a flexible porous substrate, herein we have reported the in-situ growth of BiOBr/Ag3PO4 heterostructures. BiOBr nanosheets (thickness: ~10 nm, diameter: 0.5–1 μm) and Ag3PO4 particles (size: 50–200 nm) are synthesized on CF cloth successively via a solvothermal-chemical deposition two-step strategy. CF/BiOBr/Ag3PO4 cloth displays excellent visible photoabsorption (edge: ~520 nm). Under visible-light illumination, CF/BiOBr/Ag3PO4 cloth (4 × 4 cm2) could degrade ~90.0% tetracycline hydrochloride (TCH) as a model of antibiotics in 30 min in a beaker. Especially, CF/BiOBr/Ag3PO4 cloth can be used as the filter-membrane to construct multiple photocatalytic-setup for degrading the flowing antibiotic wastewater. The removal efficiency of TCH goes up from 12.8% at the first grade to 89.6% at the sixth grade. Furthermore, the photocatalytic mechanism of CF/BiOBr/Ag3PO4 cloth and the possible decomposition pathway of TCH have been proposed based on simulation and experiment results. Therefore, the present work provides some insight for developing flexible filter-membrane-shaped photocatalysts for degrading the flowing wastewater.

Plenty of power-shaped semiconductor nanomaterials have been used to photocatalytically degrade various pollutant wastewater in beakers, but they are difficult to be applied in the practical wastewater that is flowing in river or pipeline. Thus, the key to photocatalytically degrading the flowing wastewater is to develop flexible large-scale filter-membrane with high photocatalytic activity. To address the issue, with carbon fiber cloth (CFC) as the porous substrate and TiO2/Ag3PO4 as ultraviolet/visible (UV/Vis) responsed components, we reported the in-situ growth of TiO2/Ag3PO4 nanojunctions on CFC as filter-membrane-shaped photocatalyst. The resulting CFC/TiO2/Ag3PO4 is composed of CFC whose surface is decorated with TiO2 nanorods (length: 1 ± 0.5 μm, diameter: 150 ± 50 nm) and Ag3PO4 nanoparticles (diameter: 20–100 nm). CFC/TiO2/Ag3PO4 displays a broad absorption region with two edges (~410 and ~510 nm), owing to the bandgaps of TiO2 and Ag3PO4. Under Vis or UV–Vis light illumination, CFC/TiO2/Ag3PO4 (4 × 4 cm2) can efficiently degrade more phenol (80.6%/89.4%), tetracycline (TC, 91.7%/94.2%), rhodamine B (RhB, 98.4%/99.5%) and acid orange 7 (AO7, 97.6%/98.3%) in the beaker than CFC/TiO2 or CFC/Ag3PO4. Especially, CFC/TiO2/Ag3PO4 (diameter: ~10 cm) as the filter-membrane was used to construct multiple device for degrading the flowing RhB wastewater. The removal efficiency of RhB increases from 19.6% at the 1st pool to 96.8% at the 8th pool. Therefore, this study brings some insights for purifying organic pollutants in static or flowing wastewater by using filter-membrane-shaped photocatalysts.

The non-metallic organic polymer carbon nitride has attracted widespread attentions, but its photocatalytic performance is unsatisfactory due to high recombination of photoinduced carriers. To solve this issue, we report Ag/AgCl-decorated carbon nitride (CN) nanorod heterojunctions as efficient and stable photocatalyst. CN nanorods (diameter: ∼25 nm; lengths: 1–1.5 μm) were prepared by a simple solvothermal route, and then in-situ growth of Ag/AgCl nanoparticles (diameter: 20–40 nm) on CN surface was realized by a facile co-precipitation method. Ag/AgCl-decorated CN heterojunctions with diverse Ag/CN precursor molar-ratios (0.3, 0.5, 0.7) exhibit a wide absorption spectrum from UV to visible-light region (∼750 nm). After the illumination of visible-light for 120 min, 0.5-Ag/AgCl-CN nanorods can degrade 98.5% rhodamine B (RhB), 75.4% tetracycline (TC) and 39.5% Cr(VI), obviously better than those of CN nanorods (62.6% RhB, 35.6% TC, 19.7% Cr(VI)), Ag/AgCl nanoparticles (66.5% RhB, 18.5% TC, 24.6% Cr(VI)) and Ag-CN (72.6% RhB, 39.4% TC, 28.7% Cr(VI)). This obvious improvement should result from efficient separation of photogenerated carriers. Therefore, Ag/AgCl-CN can act as an efficient and stable visible-light-driven photocatalyst.

C3N4-decorated carbon-fiber (CF) cloth has been demonstrated as flexible filter-membrane-shaped photocatalyst for degrading the flowing wastewater, but its photocatalytic activity should be further improved. To enhance the separation efficiency of photogenerated carrier, herein we inserted TiO2 between C3N4 and CF. With CF cloth as the substrate, the in-situ growth of TiO2 nanoparticles (diameter: 100–200 nm) was realized by a dip-coating/hydrothermal method; and C3N4 nanosheets (thickness: 30–50 nm) were prepared on their surface by thermal polymerization. CF/TiO2/C3N4 cloth shows excellent visible photoabsorption (edge: ∼450 nm). Under visible light irradiation, CF/TiO2/C3N4 cloth exhibits improved photocurrent and photocatalytic activity for degrading various organic pollutants (methylene blue, acid orange 7, 4-chloprophenol, tetracycline hydrochloride (TC)) and reducing heavy-metal ions (Cr(VI)), compared with CF/C3N4 and CF/TiO2 cloth. Especially, when CF/TiO2/C3N4 cloth is used as filter-membrane to photo-degrade the flowing wastewater (rate: 1.5 L h−1), the removal efficiency of TC and Cr(VI) reaches 87% and 88% after 7 grade, higher than that by CF/C3N4 cloth (60% TC, 28% Cr(VI)) and CF/TiO2 cloth (8% TC, 7% Cr(VI)). Therefore, CF/TiO2/C3N4 cloth can be used as efficient filter-membrane-shaped photocatalyst for removing various organic pollutants and heavy metal in the flowing wastewater.

The development of recyclable photocatalysts with broad-spectral photoresponse has drawn much attention for the practical application in flowing wastewater treatment. Herein, we have reported the construction of BiOBr/Ag/AgBr junctions on carbon fiber cloth (CFC) as broad-spectral-response filter-membrane-shaped photocatalyst that is efficient and easily recyclable. With CFC as the substrate, BiOBr nanosheets (diameter: 0.5–1 μm) were firstly synthesized by a hydrothermal method, and then Ag/AgBr nanoparticles (size: 100–300 nm) were prepared on the surface of CFC/BiOBr by using a chemical bath deposition route. CFC/BiOBr/Ag/AgBr presents superior flexibility and wide UV–Vis-NIR photoabsorption (from 200 to 1000 nm). Under visible light irradiation, CFC/BiOBr/Ag/AgBr (area: 4 × 4 cm2) can remove 99.8% rhodamine B (RhB), 99.0% acid orange 7 (AO7), and 93.0% tetracycline (TC) after 120 min, better than CFC/BiOBr (95.4% RhB, 55.0% AO7 and 91.2% TC). Interestingly, when CFC/BiOBr/Ag/AgBr is served as a filter-membrane in a photoreactor to purify the flowing sewage (RhB, rate: ~1.5 L h−1), the degradation rate of RhB goes up to 90.0% after ten filtering grades. Therefore, CFC/BiOBr/Ag/AgBr has great potential to purify the flowing wastewater as a novel filter-membrane-shaped photocatalyst.

Numerous nanosized photocatalysts have been demonstrated to treat antibiotic solutions efficiently in beakers, but plenty of antibiotics have been discharged to the flowing rivers. For photocatalytically degrading the flowing antibiotic wastewater, the prerequisite is to develop flexible large-scale filter-membrane with high photocatalytic activity. To solve this issue, with carbon fiber (CF) cloth as a flexible porous substrate, herein we have reported the in-situ growth of BiOBr/Ag

Plenty of power-shaped semiconductor nanomaterials have been used to photocatalytically degrade various pollutant wastewater in beakers, but they are difficult to be applied in the practical wastewater that is flowing in river or pipeline. Thus, the key to photocatalytically degrading the flowing wastewater is to develop flexible large-scale filter-membrane with high photocatalytic activity. To address the issue, with carbon fiber cloth (CFC) as the porous substrate and TiO

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For blood-contacting materials, good blood compatibility, especially good anticoagulant property is of great importance. Zwitterionic polymers have been proved to be resistant to nonspecific protein adsorption and platelet adhesion; however, their anticoagulant property is always inadequate. In this study, two kinds of zwitterionic copolymers (sulfobetaine methacrylate and sodium p-styrene sulfonate random copolymer and block copolymer) with sulfonic groups were covalently grafted from polysulfone (PSf) membranes via surface-initiated atom transfer radical polymerization (SI-ATRP) to improve blood compatibility. Field emission scanning electron microscopy (FE-SEM), attenuated total reflectance–Fourier transform infrared spectra (ATR–FTIR), X-ray photoelectron spectroscopy (XPS), and static water contact angle (WCA) were applied to characterize the morphologies, chemical compositions and hydrophilicity of the modified membranes. All the zwitterionic copolymer modified membranes showed improved blood compatibility, especially the anticoagulant property was obviously enhanced compared to the pristine PSf and simple zwitterionic polymer modified membranes. We also found that the random copolymer modified membranes showed better resistance to platelet adhesion than the block copolymer modified membranes. The zwitterionic copolymer modified membranes with integrated antifouling property and blood compatibility provided wide choice for specific applications such as hemodialysis, hemofiltration, and plasma separation.