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In this work, α-MnO 2 /BiVO 4 nanocomposites with varying MnO 2 contents (0–7 wt%) were successfully prepared via the simple chemical method. The structure, morphology, and optical properties of prepared nanocomposites were studied by various analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible absorption spectroscopy, and photoluminescence (PL) spectroscopy. The photocatalytic efficiency of α-MnO 2 /BiVO 4 nanocomposites was studied via decomposition of rhodamine B (RhB) and tetracycline (TC) under exposure to visible light (λ ≥ 420 nm). Due to good structure and composite advantages, 5%MnO 2 /BiVO 4 (MnBV-5) photocatalyst exhibited superior RhB and TC degradation efficiency to all other samples. In addition, the MnBV-5 photocatalyst showed good stability, and no apparent reduction in photocatalysis efficiency was noted after five testing cycles. Therefore, the MnO 2 /BiVO 4 nanocomposite demonstrated a good potential for photocatalytic decomposition of new water contaminants. [ABSTRACT FROM AUTHOR]

A novel photocatalyst composed of bismuth molybdate (Bi 2 MoO 6 , BMO) coupled with rhodium (Rh) nanoparticles was synthesized and evaluated for its efficiency in degrading dye contaminant under visible light irradiation. The BMO/Rh composite demonstrated a significant enhancement in photocatalytic performance, achieving a 40 % higher degradation rate of Rhodamine B (RhB) compared to bare BMO. Enhanced charge separation and reduced electron-hole recombination were primarily attributed to the synergistic effects introduced by the Rh nanoparticles. Extensive characterization techniques provided insights into the structural and mechanistic aspects of the photocatalyst. Stability tests confirmed that BMO/Rh maintained over 95 % of its initial activity after five consecutive reaction cycles, highlighting its durability. Scavenger experiments identified superoxide radicals (•O 2 -) and hydroxyl radicals (•OH) as the primary active species, contributing to the high efficiency of dye degradation. This study underscores the potential of BMO/Rh hybrids as sustainable and effective photocatalysts for environmental remediation. • Enhanced a BMO/Rh photocatalyst that improves dye degradation by 40 % under visible light. • Achieved improved charge separation with Rh nanoparticles, reducing electron-hole recombination. • Maintained over 95 % photocatalytic activity after five cycles, demonstrating high stability. • Quantified active radicals' roles in improving dye degradation efficiency. [ABSTRACT FROM AUTHOR]

Ti 3 C 2 MXenes were constructed via different strategies using HF-forming etchants or HF as etchants and were subsequently modified through alkalization to replace –F with O-containing terminal functional groups. Various analytical techniques were used to fully characterize all fabricated materials for confirming the formation of species with the desired morphologies and properties. ML-Ti 3 C 2 , etched with HF, presented a multilayered structure that made it resemble an accordion, while DL-Ti 3 C 2 , prepared using HF-forming etchants, was not completely etched, with some amounts of the parent compound's Al remaining in unformed vague laminated structures. ML-Ti 3 C 2 alkalization yielded ML-Ti 3 C 2 (OH) 2 , which was characterized by large amounts of O-containing functional groups and greatly enhanced porosity compared with that of ML-Ti 3 C 2. Methylene blue (MB) adsorption and photocatalytic degradation tests were then conducted to evaluate the functionalities of ML-Ti 3 C 2 (OH) 2 by putting it into direct application instead of being used as catalyst promoters. ML-Ti 3 C 2 (OH) 2 achieved adsorption–desorption equilibrium using MB in the dark within 30 min and 81.2% of MB was then selectively degraded over 120 min under simulated visible light irradiation. A possible degradation mechanism was proposed on the basis of the results of radical quenching experiments. This study offers a unique mechanism for directly applying MXene to the adsorption–photocatalytic degradation of organics in wastewater. For Preparation and regulation of two-dimensional Ti 3 C 2 T x MXene for enhanced adsorption-photocatalytic degradation of organic dyes in wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Designing of an effectual heterostructure photocatalyst for catalytic organic pollutant exclusion has been the subject of rigorous research intended to resolve the related environmental aggravation. Fabricating p-n junctions is an effective strategy to promote electron-hole separation of semiconductor photocatalysts as well as enhance the organic toxin degradation performance. In this study, a series of n-type NiAlFe-layered triple hydroxide (LTH) loaded with various ratios of p-type MoS 2 was synthesized for forming a heterostructure LTH/MoS 2 (LMs) by an in situ hydrothermal strategy. The photocatalysts were characterized by XRD, SEM&EDX, TEM, FT-IR, XPS, as well as UV–vis DRS. The photoactivity of photocatalysts was tested by the degradation of Indigo Carmine (IC) dye. The optimized catalyst (LM1) degrades 100% of indigo dye in high alkaline pH under UV light for 100 min. Besides, the degradation rate of LM1 is 15 times higher than that of pristine NiAlFe-LTH. The enhanced photoactivity is attributed to the synergistic effect between NiAlFe-LTH and MoS 2 as well as the p-n junction formation. [Display omitted] • A facile method for synthesizing heterostructure-LMs photocatalyst is suggested. • The best photocatalytic performance was found in LM1 samples for dye degradation. • Superior adsorptive-photocatalytic activity of LM1 was revealed under visible light. • Photocatalytic performance of LMs was effectively exhibited even at high pH over 11. • The recyclability and mechanism of photocatalysis of LMs was identified. [ABSTRACT FROM AUTHOR]

In pursuit of the appropriate method for complete removal of organic effluents from surface water, Ag modified g-C 3 N 4 materials as a photocatalyst gained considerable attention. In this paper, Ag doped g-C 3 N 4 materials were prepared by a facile one-pot pyrolysis method. The synthesized photocatalysts were studied using different analytical techniques like XRD, HR-TEM, XPS, UV, FTIR, PL spectroscopy, etc. The prepared photocatalyst materials were used for the visible light photodegradation of IC dye as an organic pollutant and for self-cleaning applications. The obtained results indicate that the optimized Ag doped g-C 3 N 4 (CNA-1) sample exhibits 79.97 % degradation efficiency in 30 min with efficient self-cleaning performance. The enhanced photocatalytic activity of CNA-1 can be attributed to the incorporation of Ag, which plays a pivotal role in absorbing visible light. Furthermore, cycling tests were employed to evaluate the stability and reusability of material. The possible photocatalytic mechanism was proposed from trapping experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

• A 2D covalent organic framework Por-PD-COF as selective adsorbent and photocatalyst was designed and synthesized. • Por-PD-COF could selectively and competitively adsorb MB from the mixed organic dyes aqueous solution. • Por-PD-COF could photodegrade MB effectively under visible light. • Por-PD-COF can be recycled and reused after absorption or photocatalysis. In this work, amide bonds linked 2D porphyrin-based covalent organic framework (Por-PD-COF) was designed and synthesized through condensation reaction between meso -tetrakis (p -carboxyphenyl) porphyrin (TCPP) and para -phenylenediamine (PD). Large surface area, abundant active sites and good stability of Por-PD-COF made it can quickly and efficiently absorb methylene blue (MB) selectively and remove it from aqueous solution. More importantly, in different mixture of organic dyes including RhB and MB, MB and MO, Por-PD-COF can selectively adsorb MB with a large adsorption capacity (328.57 mg·g−1), while a little MO and hardly RhB because of the unique charge selectivity and specific pore size. Especially in the mixture solution of MO and MB, compatitive adsorption appeared, MB can substitute the adsorbed MO on the active sites in the channel of Por-PD-COF. Furthermore, with the band gap narrow to 1.02 eV, Por-PD-COF could be used as efficient photocatalyst to degrade MB (99%, 180 min) directly under visible light irradiation, and can be reused for four times with almost no absorptive and photocatalytic capacity losing. The possible adsorption and photocatalytic mechanisms of Por-PD-COF were also proposed. As a result, with the uncomplicated preparation, effective and selective adsorption and reusability, Por-PD-COF was a promising specific adsorbent and photocatalyst for further application in specific organic molecules separation and organic waste removal from aqueous solution. [ABSTRACT FROM AUTHOR]

Photodegradation of organic pollutants using metal oxides has shown extraordinary promise owing to the catalytic efficacy, low cost, less noxiousness, and good chemical constancy. In this research, pure and transition metal ions (Cu)-doped V 2 O 5 nanosheets were synthesized and investigated for their photocatalytic efficiency using methyl blue (MB) and rhodamine B (RhB) organic dye pollutants under visible light irradiation. The orthorhombic crystal phase was confirmed by XRD analysis, which exhibited a stable phase upon incorporating Cu dopant ions. Optical properties were examined using optical absorption spectroscopy, while a reduced band gap was observed in the doped V 2 O 5 nanosheets over the undoped sample. EIS analysis confirmed lower charge resistance in doped V 2 O 5 nanosheets. The Cu dopant incorporation into the host matrix considerably enhanced photodegradation efficiency for MB and RhB impurities under light illumination. The improvement in catalytic efficacy is attributed to dopant ions that can separate photoinduced charge carriers and the quick movement of the charge. Moreover, comparatively lesser crystalline size, improved specific surface area, and hydroxyl group onto the catalyst surface are quite advantageous to offer better photocatalytic activity of Cu-doped V 2 O 5 nanosheets. [Display omitted] • Pure and Cu-doped V 2 O 5 nanosheets were synthesized using hydrothermal method. • XRD analysis confirmed orthorhombic crystal phase of synthesized materials. • Photodegradation of MB and RhB pollutants were examined under visible light. • Doped V 2 O 5 catalyst shows 95.4% and 91.2% degradation of MB and RhB. • · O 2 −, OH · species played a major contribution in the removal toxic pollutants. [ABSTRACT FROM AUTHOR]

The present work demonstrates a facile hydrothermal synthesis of Plasmonic Au–TiO 2 nanocatalyst followed by its successful application for complete photocatalytic dye degradation (oxidation) in batch and continuous flow process under natural sunlight as well as visible and UV light. The Au-TiO 2 nanocatalyst was synthesized by a hydrothermal method at basic pH conditions. It was meticulously analyzed by a variety of spectroscopic (UV-Vis, Raman, FTIR, PL, Powder XRD, ED-XRF, XPS), microscopic (FE-SEM with elemental mapping, TEM), and thermal (DSC) techniques. The characterization results showed that monodisperse Plasmonic Au(0) nanoparticles with a mean diameter of 12 ± 1 nm are homogeneously deposited on Anatase TiO 2 crystals. The nanocatalyst showed complete photocatalytic degradation of various dye compounds (Eosin Yellowish, Indigo Carmine, Methyl Orange, Methylene Blue, and Rhodamine B) under visible light or sunlight as confirmed through UV-Vis spectra, mass spectral study, and TOC analysis of dye solutions. A continuous flow process using a specially designed photoreactor was accomplished with a long catalyst lifespan, easy processibility, and low cost. Easy synthesis of the catalyst, its very detailed characterization, and its efficient catalytic studies to completely degrade various dye molecules under visible light source in the absence of any added oxidizer (O 2 , H 2 O 2 , KMnO 4 , Organic peroxides) and the demonstration of continuous flow process are significant highlights of the present work. A plausible mechanistic pathway is also presented in line with the previous literature reports and presently observed phenomenon. [Display omitted] [ABSTRACT FROM AUTHOR]

Adopting a facile one-step solvothermal method, CN/MgAl 0.80 Ce 0.20 -LDH, a lamellate composite of graphitic carbon nitride (g-C 3 N 4 , CN) and Ce-doped MgAl-layered double hydroxide (LDH), was synthesized. Profiting from the combined effect of Ce-doping and CN-LDH composition, CN/MgAl 0.80 Ce 0.20 -LDH possesses large specific surface area (52.71 m2 g−1) and high separation efficiency of photogenerated charge. When used to remove organic dye Congo red (CR), the composite exhibits enhanced efficiency which can be attributed to the synergetic performance of adsorption and photocatalysis. As a result, ~49% CR (50 mg L−1) can be adsorbed by CN/MgAl 0.80 Ce 0.20 -LDH and the CR degradation efficiency exceeds 90% within 180 min under light-emitting diode (LED) visible light irradiation, which is much higher than that of pristine CN (48.77%). The augmented surface area and proliferated active sites benefit the increase of adsorption capacity. The enhanced photocatalytic performance can be attributed to the efficient transmission of photogenerated electrons and holes between CN and MgAl 0.80 Ce 0.20 -LDH. Electrochemical impedance spectroscopy (EIS) analysis and photoluminescence (PL) analyses confirmed the effective separation of photogenerated electron-hole pairs in CN/MgAl 0.80 Ce 0.20 -LDH, while electron spin resonance (ESR) results verified the derivation of superoxide radicals (·O 2 -) species amid CR photocatalytic degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

• MnS/Ag 2 WO 4 NCs was prepared by chemical co-precipitation method. • The NCs showed efficient visible light photocatalytic activity than individual particles. • MnS/Ag 2 WO 4 showed potent anti-microbial activity against gram positive and gram negative microorganisms. • Experimental results demonstrated that OH• and •O2- are the major reactive species involved in dye degradation. • MnS/Ag 2 WO 4 NCs showed MB dye degradation potency of 92.3%. In this study, the novel MnS/Ag 2 WO 4 photocatalyst was synthesized via chemical co-precipitation method and investigated its physical and structural characteristics using HR-TEM, N 2 adsorption and desorption studies, FT-IR, EDAX, PL, UV–vis DRS, ESR, XPS and XRD. The estimation of photocatalytic activity of synthesized photocatalysts was done using methylene blue (organic dye) in aqueous solution. The photocatalyst efficiency was superior for MnS/Ag 2 WO 4 with degradation of 92.3% when compared with bare MnS (67.23%) and Ag 2 WO 4 (58.93%). The kinetic study reveals that higher reaction kinetic rate achieved by the MnS/Ag 2 WO 4 compared with MnS and Ag 2 WO 4. The scavenging test reveals that •OH and O2-• took the important part in the degradation process. The six cycles test reveals that the photocatalyst is highly reusable by showing similar degradation efficiency throughout the six cycles. MnS/Ag 2 WO 4 was also possessed potential broad spectrum anti-microbial activity against B. subtilis and E. coli. Hence, MnS/Ag 2 WO 4 heterostructure can be used as an excellent photocatalyst as well as an effective anti-microbial agent. MnS/Ag 2 WO 4 would be a cost-effective, highly efficient photocatalyst and a good antimicrobial agent. [ABSTRACT FROM AUTHOR]