Search

Photosystem I/dithiol molecular wire/nanoparticle bioconjugates have been shown to photocatalytically generate dihydrogen at linear rates when continuously illuminated. In an effort to maximize H2production, the pH and ionic concentration of the solution, the mobility of the electron donor, the length and degree of saturation of the molecular wire, and the intensity of the light were systematically investigated. Optimal conditions included a solution buffered at pH 6.0, cross-linked plastocyanin, rebuilt spinach PS I, and the use of 1,4-benzenedithiol to connect PS I to the Pt nanoparticle. Illumination of this optimized Photosystem I/dithiol molecular wire/nanoparticle bioconjugate at a light intensity of 70 μE m−2s−1generated a measured one time H2production rate of 312 μmol H2mg Chl−1h−1. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) WO3nanostructures were grown on carbon paper by a catalyst-free high temperature reactive vapor deposition process, which exhibit a good photoelectrochemical property and visible light driven photocatalytic performance. [ABSTRACT FROM AUTHOR]

In this paper, a NiAl-LDH with the characteristic structure of a hydrotalc-like compound was applied as a carrier in a two-step hydrothermal process, and a MnCdS/In2S3/NiAl-LDH composite material was successfully prepared by loading MnCdS and In2S3 on the flower spherical-like surface of NiAl-LDH. The combination of NiAl-LDH with In2S3 and MnCdS made the band gap smaller and the light absorption range larger, thus increasing the utilization rate of light. 50% MnCdS/In2S3/NiAl-LDH composites had the best photoinduced charge separation and highest surface enrichment of photogenerated electrons. In the degradation experiment of crystal violet (CV), 50% MnCdS/In2S3/NiAl-LDH composites showed superior photocatalytic degradation efficiency (>98.5%) under full spectrum light. Furthermore, the applicability and universality of photocatalysts were studied by observing the degradation of CV by MnCdS/In2S3/NiAl-LDH composites under different conditions. In addition, the composites showed excellent hydrogen production capacity in the photolysis of water, in which hydrogen production within 8 hours was about 7661.51 μmol g−1. By combining the results of active species capture experiments, density functional theory (DFT) calculations and photoelectrochemical experiments, the possible mechanism of double S-scheme heterojunction photocatalysis among NiAl-LDH, In2S3 and MnCdS was inferred, which is one of the main reasons for the enhancement of photocatalytic activity. [ABSTRACT FROM AUTHOR]

We have developed a green method to reduce graphene oxide viaa UV-irradiated photoreduction process in which H3PW12O40was used as photocatalyst. Moreover, H3PW12O40can adsorb on the reduced graphene oxide as anionic stabilizer and lead to water dispersible graphene sheets. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

The activation capacity of molecular oxygen is an important indicator to evaluate the photocatalytic efficiency of photocatalysts. In this paper, WS2 nanosheet was deposited on hyper-crosslinked CTF-1-G (obtained by molecular expansion from covalent triazine framework CTF-1) to form a C-GW heterojunction, which promoted the photodegradation of pollutants and the activation of molecular oxygen. This novel C-GW heterojunction exhibited excellent degradation property for organic pollutants (tetracycline (TC), rhodamine B (RhB)) and activating molecular oxygen under visible light irradiation. Among them, C-GW15 could degrade 98% of 20 ppm TC in 60 min and 99% of 30 ppm RhB in 30 min, and it had the highest hydrogen generation rate and hydrogen production amount in 4 hours, which were 8.74 mmol h−1 g−1 and 34.94 mmol g−1, respectively. Meanwhile, C-GW15 had the strongest 3,3′,5,5′-tetramethylbenzidine oxidation capacity and could generate 1.83 μmol of ˙O2− in 60 min and the production of H2O2 was 20.8 μmol L−1 in 40 min. The results of this study clearly indicated that the combination of WS2 and CTF-1-G can enhance the visible light absorption capacity and photogenerated carrier separation efficiency, thus promoting the photocatalytic performance. Finally, a Z-type photocatalytic mechanism was proposed based on radical capture, molecular oxygen activation experiments and electron spin resonance analysis. These findings will extend the fundamental understanding of the Z-type photocatalytic mechanism and provide new opportunities for the rational design of CTF heterojunctions for the treatment of environmental pollution and clean energy conversion. [ABSTRACT FROM AUTHOR]

Reports about polyethylene terephthalate (PET) fabrics with durable superhydrophobicity and flame retardance are very limited. In this paper, durable superhydrophobic, photocatalytic, flame-retardant (FR) PET fabrics were fabricated for the first time by a green approach and further employed for various applications. Through layer-by-layer (LBL) alternate deposition of mixed polyelectrolytes, including branched poly(ethylenimine) (BPEI), phytic acid (PA), and ammonium polyphosphate (APP), the fabric obtained superior self-quenched flame retardance through deposition of only two bilayers (BL). The fire burned very slowly, and was self-extinguished after ignition for 8 s. The fabric was also anti-dripping. When the FR fabric was further coated with a layer of PDMS-grafted-TiO2@PDMS coating, it presented excellent superhydrophobicity and self-cleaning properties both under air and water conditions. Moreover, the final fabric showed durable superhydrophobicity, which presented resistance to repeated rinsing treatments, repeated peeling by adhesive tape, and cyclic abrasion treatments. This fabric also showed superior photocatalysis capability and photocatalytically stable superhydrophobicity. The finally coated fabrics could selectively and highly efficiently remove polluted oils from water and separate oil–water mixtures. This multifunctional fabric is believed to show very promising application potential in the flame retardance, superhydrophobicity, self-cleaning, water purification, liquid separation, and photocatalysis fields. [ABSTRACT FROM AUTHOR]

A hierarchical structured nanofibrous anatase-titania-cellulose composite was obtained by hydrothermal treatment of ultrathin titania gel film pre-coated nanofibres in a bulk cellulosic substance (common commercial filter paper). The initial titania gel films were transformed to anatase nanoparticles evenly deposited on the surface of each cellulose nanofibre. The resulting anatase-titania-cellulose composite maintained the initial hierarchical network structure of the filter paper. The diameters of the anatase titania nanoparticles anchored on the surface of the cellulose nanofibres varied from 20 nm to 50 nm. The hierarchical structured nanofibrous anatase-titania-cellulose composite shows significant photocatalytic performance towards degradation of methylene blue and methyl orange aqueous solutions under UV light irradiation. Moreover, the methylene blue which was directly dropped onto the surface of the anatase-titania-cellulose composite sheet was found to be decomposed after 1 h outdoor sunlight irradiation. [ABSTRACT FROM AUTHOR]

Metal halide perovskites with suitable energy band structures and excellent visible-light responses have emerged as promising photocatalysts for CO2 reduction to valuable chemicals and fuels. However, the efficiency of CO2 photocatalytic reduction often suffers from inefficient separation and sluggish transfer. Herein, a step-scheme (S-scheme) CsPbBr3/BiOBr photocatalyst with oxygen vacancies possessing intimate interfacial contact was fabricated by anchoring CsPbBr3 QDs on BiOBr-Ov nanosheets using a mild anti-precipitation method. The results showed that CsPbBr3/BiOBr-Ov-2 with an internal electric field (IEF) heterojunction exhibited a boosted evolution rate of 27.4 μmol g−1 h−1 (CO: 23.8 μmol g−1 h−1 and CH4: 3.6 μmol g−1 h−1) with an electron consumption rate (Relectron) of 76.4 μmol g−1 h−1, which was 5.9 and 3.2 times that of single CsPbBr3 and BiOBr-Ov, respectively. Density functional theory (DFT) calculations revealed that BiOBr with oxygen vacancies can effectively enhance the adsorption and activation of CO2 molecules. More importantly, in situ infrared Fourier transform spectroscopy (DRIFTS) spectra show the transformation process of the surface species, while the femtosecond transient absorption spectrum (fs-TA) reveals the charge transfer kinetics of the CsPbBr3/BiOBr-Ov. Overall, this work provides some guidance for the rational design of S-scheme heterojunctions and vacancy-engineered photocatalysts, which are expected to have potential applications in the fields of photocatalysis and solar energy conversion. [ABSTRACT FROM AUTHOR]

Significant global concerns about the environment include the removal of various organic dye contaminants and the detection of toxic nitrite (NO2−). Herein, we developed a novel composite that combines an inorganic perovskite-based alkaline earth stannate (CaSnO3) with aurivillius oxide (Bi2WO6). These components were synthesized by combustion and hydrothermal methods, respectively. The composite was designed for the photocatalytic degradation of methylene blue (MB) and electrochemical sensing of nitrite. The prepared composite was systematically characterized using various analytical techniques to verify its elemental composition and morphology and to determine the particle size and band gap. CaSnO3/Bi2WO6 exhibited a remarkable 92.5% degradation of the carcinogenic MB dye under UV light over approximately 180 minutes. Importantly, it was observed that the designed nanocomposite did not exhibit photo-corrosion properties as the degradation of MB occurred even at pH 11. Furthermore, the CaSnO3/Bi2WO6-modified glassy carbon electrode (GCE) demonstrated excellent electrocatalytic activity, with an obtained limit of detection (LOD) of 0.9 μM. In this work, the CaSnO3/Bi2WO6 nanocomposite shows promising potential for efficient photocatalytic dye degradation and electrochemical sensing of nitrite, with the added advantage of avoiding photo-corrosion even under alkaline conditions. [ABSTRACT FROM AUTHOR]

We present photophysical studies on homoleptic zinc-dipyrrin complexes representing intramolecular donor–acceptor systems. Intramolecular charge transfer depends on ligand variation and intermolecular environmental influences. In particular, we focus on steady-state and transient absorption methods to compare the response of the ligand dynamics with that of the complexes after photoexcitation. For the first time, we successfully tested zinc bis(dipyrrinato) complexes as photocatalysts in two different aerobic photooxidation reactions. Early-time dynamics after 100 fs in dichloromethane and in ethanol can be assigned to charge transfer states, while the subsequent response constitutes broad-band excited state dynamics, most likely of overlapping singlet and triplet states when probed in a relatively wide spectral window from 350 to 1400 nm and up to a delay time of 1.6 ns. In addition, a strong correlation between steady-state and time-resolved experiments makes this experimental approach a versatile tool for future investigations of this class of molecules, especially with respect to photocatalysis. The results of this study underpin the need for further development for quantifying amplitudes of the excited state population of electronically excited singlet and triplet states. [ABSTRACT FROM AUTHOR]

The present investigation utilizes density functional theory (DFT) to elucidate the influence of iron (Fe) and ruthenium (Ru) as dopants, alongside sulfur (S) co-doping, on the electronic properties and photocatalytic properties of zinc oxide (ZnO) monolayer nanosheets. The findings indicate that the integration of Fe and Ru dopants serves to augment structural stability while concomitantly diminishing the bandgap energy through an elevation of the valence band maximum (VBM). Doping of Fe and Ru along with co-doping up to three sulfur atoms into the ZnO lattice has been observed to result in a compromise of structural stability while concurrently enhancing the specific surface area. The introduction of sulfur expands the bandgap in Fe-doped ZnO nanosheets, enhancing the VBM energy, while for Ru-doped ZnO nanosheets, sulfur doping narrows the bandgap. This effect is especially notable in RuS3 co-doped nanosheets, making them well-suited as a photocatalyst for the overall water splitting process at pH = 7. Furthermore, the increased probability of effective electron–hole pair separation, combined with a bandgap of 3.52 eV, positions FeS-co-doped ZnO as a promising photocatalytic material for the generation of hydrogen via water splitting under near-ultraviolet illumination. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) containing S heteroatom are promising materials for applications in photocatalysis due to their donor–acceptor-type structures, which can improve the mobility of carriers in polymers. Herein, a series of composites (TTBT-COF@PEGx, x = 10, 20, and 30) were prepared based on CTF containing S heteroatom and polyethylene glycol (PEG) by a two-step reaction. The results show that the photocatalytic hydrogen evolution rate of TTBT-COF@PEG30 is 1.51 times that of pristine TTBT-COF. This significant improvement was attributed to PEG in the pores, which resulted in a stable layered structure, reuced distortion and deformation of the skeleton, and rapid separation and transportation of photogenerated electron holes. [ABSTRACT FROM AUTHOR]

A theoretical study of the reported photocatalytic systems based on Zr-based MOF (UiO-67) with biphenyl-4,4′-dicarboxylic acid (bpdc) and 2,2′-bipyridine-5,5′-dicarboxylic acid (bpydc) as linkers was performed. Quantum chemical calculations were carried out to understand the optical properties of the materials and to facilitate the rational design of new UiO-67 derivatives with potentially improved features as photocatalysts under ambient conditions. Hence, the effect of the structural modifications on the optical properties was studied considering different designs based on the nature of the linkers: in 1 only the bpdc linker was considered, or the mixture 1 : 1 between bpdc and bpydc linkers (labeled as 1A). Also, substituents R, –NH2, and –SH, were included in the 1A MOF only over the bpdc linker (labeled as 1A-bpdc-R) and on both bpdc and bpydc linkers (labeled as 1A-R). Thus a family of six isoreticular UiO-67 derivatives was theoretically characterized using Density Functional Theory (DFT) calculations on the ground singlet (S0) and first excited states (singlet and triplet) using Time-Dependent Density Functional Theory (TD-DFT), multiconfigurational post-Hartree–Fock method via Complete Active Space Self-Consistent Field (CASSCF). In addition, the use of periodic DFT calculations suggest that the energy transfer (ET) channel between bpdc and bpydc linkers might generate more luminescence quenching of 1A when compare to 1. Besides, the results suggest that the 1A-R (R: –SH and NH2) can be used under ambient conditions; however, the ET exhibited by 1A, cannot take place in the same magnitude in these systems. These ET can favor the photocatalytic reduction of a potential metal ion, that can coordinate with the bpydc ligand, via LMCT transition. Consequently, the MOF might be photocatalytically active against molecules of interest (such as H2, N2, CO2, among others) with photo-reduced metal ions. These theoretical results serve as a useful tool to guide experimental efforts in the design of new photocatalytic MOF-based systems. [ABSTRACT FROM AUTHOR]

Graphdiyne is an emerging material widely used in photocatalysis. Its excellent physicochemical properties, such as nonuniform electron distribution, uniform pore distribution, excellent electron mobility, and high chemical stability, make it promising for solar fuel production. Given the rapid development of graphdiyne-based photocatalysts and their application in solar fuel production, a timely review of this field is urgently needed. This paper summarises the structure, properties, synthesis and characterisation of graphdiyne, and the achievements of graphdiyne-based photocatalysts in solar fuel production, including H2 evolution, CO2 reduction and N2 fixation. The challenges and outlook of graphdiyne-based photocatalysts for efficient solar fuel production are presented. This paper is expected to provide new insights into graphdiyne-based photocatalysts for solar fuel production. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production has garnered considerable attention as a latent solution to various energy challenges. Because of their distinct optical characteristics, persistent luminescence nanoparticles (PLNPs) can emit light long after illumination ends, making them highly advantageous for round-the-clock photocatalysis. However, photocatalytic activity is currently restricted owing to the low specific surface area and the high number of photogenerated electron–hole pairs. In this study, PLNP (ZnGa5Si5O18)/sulfur-doped carbon nitride (SCN) was synthesized via a solvothermal method and calcination. Under irradiation with a xenon lamp, the resulting PLNPs/SCN (1 : 1) composite exhibited excellent photocatalytic hydrogen evolution activity, with a hydrogen evolution rate of 3963.80 μmol g−1 h−1, which was 15 times and 1.4 times higher than that of PLNPs (307.1 μmol g−1 h−1) and SCN (2800.80 μmol g−1 h−1), respectively. The formation of a stable type II heterojunction is responsible for the high photocatalytic activity. This heterojunction effectively suppressed the electron–hole complexation generated during photoexcitation and enhanced the carrier flexibility. In addition, the PLNPs/SCN (1 : 1) composite had a larger specific surface area than the PLNPs. The synthesis of this novel composite heterojunction under mild conditions not only provides a new strategy for preparing PLNP-based composite catalysts but also holds significant potential for enabling round-the-clock photocatalysis. [ABSTRACT FROM AUTHOR]

Asymmetric photocatalysis consists of the synergistic effect of photocatalysis and organocatalysis, in which the photoelectrons in photocatalysts catalyze substrates to produce free radical intermediates, and chiral substances can control the stereoscopicity. However, photocatalysts are mainly concentrated in noble-metal materials, and perovskites with excellent photoelectric properties are rarely applied in asymmetric catalysis, mainly due to their susceptibility to catalytic environments. Hence, we embedded CsPbBr3 quantum dots into KIT-6 mesoporous silica to form silica-shell-protected heterogeneous photocatalysts (CsPbBr3@KIT-6), which were further combined with chiral organocatalysts to explore the activity and stereoselectivity in asymmetric photocatalysis. The well-dispersed CsPbBr3 in KIT-6 channels provides more active sites and exhibits excellent enantioselectivity in the formation of the C–C bond and cross-dehydrogenation coupling of C–H bonds (75.3–91.3% and 74.9–94.0%, respectively). Meanwhile, the turnover number (TON) of the 20CsPbBr3@KIT-6 photocatalyst with 20 wt% of CsPbBr3 reaches at least 36 700, which is 215 times higher than that of noble metal Ru photocatalysts in an N2 atmosphere and 458 times higher in an air atmosphere. [ABSTRACT FROM AUTHOR]

A series of defective MnmIn2S3+m (m = 1–5, integer) microflowers were successfully synthesized via a facile hydrothermal method and characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). These solid solution photocatalysts have similar cubic phase crystal structures. The results of electron paramagnetic resonance (EPR) spectra showed that the concentration of sulfur vacancy (VS) increased with the increase in Mn/In atomic ratio. The photocatalytic performance of the prepared MnmIn2S3+m was evaluated by the reduction of Cr(VI) in aqueous solution under simulated sunlight, in which Mn4In2S7 showed the highest photocatalytic activity. 40 ppm K2Cr2O7(VI) was almost completely reduced to Cr(III) within 60 minutes. Additionally, the photocatalytic mechanism was investigated and it was demonstrated that the appropriate concentration of VS could accelerate the carrier separation and transfer of Mn4In2S7, so as to improve the photocatalysis efficiency. This work will expand the application of solid solution photocatalysts in the future. [ABSTRACT FROM AUTHOR]

Since the famous Swedish chemist Scheele described molybdenum blue for the first time in 1778, polyoxometalate (POM) chemistry has made significant progress in its more than 200-year history. Compared with the POM chemistry of Mo, W and V, significant improvement of polyoxotantalates (POTas) occurred mainly during the last few years. In this paper, complexes with different structures, including isopolyoxotantalates (IPOTas), organic–inorganic hybrid POTas, Ta/W mixed POMs and heteropolyoxotantalates (HPOTas) with their derivatives, are reviewed, aiming at providing some useful guidance for further exploration and discovery of more exciting POTas with innovative architectures and excellent performances. Herein, we highlight and discuss the structural features of POTas according to various structural types. In addition, the synthesis strategies and related applications, especially in photocatalysis, are reviewed. [ABSTRACT FROM AUTHOR]

Although a lot of titanium oxo-clusters (TOCs) have been synthesized and characterized, research studies on their application properties are still limited. The work described here is not only aimed at the synthesis and crystal structures of the TOCs, but also aimed at exploration of their potential applications in molecule based fluorescence labelling and photocatalysis. Three heterometallic TOC compounds with lanthanide (Ln) elements Sm(iii) (1), Eu(iii) (2) and Gd(iii) (3) are prepared and their cluster structures are characterized as LnTi11 cages. Compound 2 exhibits the characteristic fluorescence of Eu(iii) and the emission intensity can be decreased upon irradiation and recovered by air oxidation, which is attributed to the energy transfer between Eu(iii) and photo-induced Ti(iii) of the oxo-TiO cluster. The fluorescence intensity of 2 can be significantly increased when treated with 1,10-phenanthroline. The catalytic properties of 2 were determined by the degradation of dyes on a paper substrate. Compound 2 has potential applications as a molecule based fluorescent labelling agent and photodegeneration catalyst. [ABSTRACT FROM AUTHOR]

In this comment, we found that the explanations in the paper of X. Yang et al. were not accurately stated, which could cause confusion and misunderstanding. We hope that this comment can clarify this paper and provide more precise insights into the work of X. Yang et al. Also, the new mechanism of the enhanced activity of photocatalysis was discussed from our point of view, and the effective band gap of the composite can be calculated, which can possibly be an important factor for indicating the activity of the photocatalyst. [ABSTRACT FROM AUTHOR]

Ultrafine hybrid Cu2O–Fe2O3 NPs have been prepared using the supramolecular assemblies of hexaphenylbenzene (HPB) derivative 3 as nanoreactors and stabilizers. The as-prepared hybrid Cu2O–Fe2O3 NPs serve as an efficient and recyclable photocatalytic system for carrying out C–N coupling between aryl halides and various amines (aliphatic, aromatic and N-heterocyclic) at room temperature in mixed aqueous media under visible light irradiation. Amazingly, Cu2O–Fe2O3 NPs also exhibited high efficiency in the reactions involving the synthesis of biologically important N-substituted carbazole derivatives. The work being presented in this article demonstrates the preparation of a ‘dip strip’ coated with the as-prepared catalytic system and utilization of this paper strip as a recyclable and portable heterocatalytic system for carrying out the Ullmann–Goldberg coupling. [ABSTRACT FROM AUTHOR]

In the domain of photocatalysis, the oxygen evolution reaction (OER) serves as a crucial process in sustainable energy production. The development of efficient photocatalysts for the OER is therefore highly desirable. Two-dimensional (2D) materials, with their distinct structural and electronic properties, offer great opportunities for improving oxygen production. We propose H and H′ polymorphs of SnGe2N4 as appealing photocatalysts driving the OER using first-principles calculations together with non-adiabatic molecular dynamics (NAMD). The electronic properties and charge carrier dynamics of SnGe2N4 were evaluated, revealing insights into its potential for the OER under solar irradiation. Our findings indicate that SnGe2N4 has a favorable bandgap (∼2 eV) with appropriate band edges for the OER, promoting charge separation and transport. A significant difference in mobility facilitates electron and hole separation, leading to elevated reaction rates in the material. Moreover, the band edge alignment suggests the incorporation of water oxidation potential favoring the OER. The computed reaction pathways and free energy analysis show that SnGe2N4 can function as an effective photo-catalyst for the OER. Non-adiabatic coupling (NAC) matrix elements further ensure the ultrafast carrier dynamics, facilitating efficient charge transfer and slow recombination rates. Our findings highlight 2D SnGe2N4 as an appealing candidate for the OER. [ABSTRACT FROM AUTHOR]

1D FeS–FeS2@TiO2 heterojunctions were developed to investigate the photoexcited charge separation and transportation to active sites for improved photocatalytic properties. Morphological, optical, and spectroscopic studies on the photoanodes demonstrated excellent interfacial interaction, homogeneity, and wide solar light sequestering. Photoelectrochemical studies optimized the sensitizer loading of the 10-FeS–FeS2@TiO2 heterojunction that possesses the highest photocurrent of 1.74 mA cm−2 as compared to pure TiO2 NTs with a photocurrent of 0.30 mA cm−2 at 0.3 V versus Ag/AgCl (1.23 V RHE) under a light intensity of 100 mW cm−2. Also, 10-FeS–FeS2@TiO2 NTs showed an excellent charge carrier donor density (ND) of 3.86 × 1017 cm−3 and consequently the least electron–hole (e−/h+) pair recombination was observed. Redox shuttling of FeS–FeS2 with high surface area TiO2 NTs resulted in excellent electron–hole pair charge separation and transportation via the optimized loading and uniformity of the sensitizer. The current strategy has paved the way for the development of efficient photocatalysts for enhanced photoexcited charge separation and transportation during photocatalysis. [ABSTRACT FROM AUTHOR]

Current heterogeneous photocatalysis faces the major bottlenecks of limited mass transfer, charge recombination and tedious immobilization of expensive photocatalysts. In this work, fac-Ir(ppy)3 is directly anchored at a low cost via covalent linkage to poly(4-vinyl benzyl chloride) (PVBC) brushes grafted on SiO2 nanoparticles (PVBC@SiO2 NPs) via Friedel–Crafts alkylation, affording PVBC@SiO2 NP-supported fac-Ir(ppy)3 with high luminous efficacies such as emission lifetime and quantum yield. In the reductive cross-coupling of benzaldehydes/acetophenones with 1,4-dicyanobenzene (1,4-DCB), the as-fabricated photocatalyst affords benzhydrols in the same yields as homogeneous fac-Ir(ppy)3, except for o-substituted benzaldehydes/acetophenones. In terms of the same yields as homogeneous fac-Ir(ppy)3, a new catalytic model, named homogeneous-like photocatalysis, is proposed. In this catalytic model, the open stretching of PVBC brushes in DMSO enables the anchored fac-Ir(ppy)3 to catalyse the reaction in a similar manner as homogeneous fac-Ir(ppy)3, effectively avoiding charge recombination and mass transfer limitation. Furthermore, no significant decrease in yield (<5%) is observed over eight catalytic cycles, due to the good chemical and mechanical stabilities of PVBC@SiO2 NP-supported fac-Ir(ppy)3. Overall, the immobilization of fac-Ir(ppy)3 onto the PVBC brushes grafted on SiO2 NPs provides a mass/charge transfer-enhanced platform for supported photocatalysts. [ABSTRACT FROM AUTHOR]

A cryptand-like Ti-coordination compound, namely Ti12Cs, comprising two Ti6-salicylate cages and hosting two Cs+ ions, was synthesized by the solvothermal method. It exhibits strong visible-light absorption with an absorption band edge of 652 nm, attributed to the electron transition from salicylate ligands to Ti ions. Electrochemical impedance, visible-light transient photocurrent response, and photoluminescence spectra confirm that Ti12Cs has excellent visible-light response and charge-separation properties. Ti12Cs can be used as a heterogeneous and recyclable photocatalyst for CO2/epoxide cycloaddition, with high utilization efficiency of visible-light under mild conditions. The mechanism investigation points to a synergistic effect of photocatalysis and Lewis acid catalysis. [ABSTRACT FROM AUTHOR]

CH-arylated quinolines have found widespread applications in drug discovery as well as in the field of fine chemicals and material science. Herein, we report a general, transition-metal-free, environmentally friendly photocatalytic strategy for the direct C–H arylation of quinolines and quinoline N-oxides/pyridines selectively at the C-8 and C-2 positions, respectively, using chlorophyll as the organic photocatalyst. This method offers a simple, practical route for direct access to C8-aryl quinolines, C2-aryl pyridines, and quinoline N-oxides. The key advantages of the present protocol include operational simplicity, the use of clean energy sources, low reagent costs, and no requirement of pre-functionalized substrates. [ABSTRACT FROM AUTHOR]

Halide perovskites have high photoelectric conversion efficiency, making them promising candidates for photocatalysis. However, their toxic and unstable nature limits their applications. Here, we successfully synthesised three hybrid Bi-based halide perovskites: (HTMG)3Bi2Br9 (1), (HEI)2BiBr5 (2) and (HTMA)3Bi2Br9 (3). X-ray single-crystal diffraction analysis shows that they all contained 0D structures composed of isolated Bi–Br clusters. The three compounds showed excellent degradability and cycling stability for Sudan III dissolved in ethanol under simulated sunlight. In addition, the photocatalytic degradation performance of four Bi-based halide perovskites previously reported by our group is also characterised and summarised in this work. [ABSTRACT FROM AUTHOR]

Three-dimensional rose-like ZnO (R-ZnO) is an appealing photocatalyst due to its remarkable properties, while it is also essential to boost its current visible light photocatalytic performance. In this study, R-ZnO was prepared by the hydrothermal method, and oxygen vacancies and Ag nanoparticles were introduced by calcining the ZnO precursor in an argon atmosphere and the photoreduction method, respectively, to improve the photocatalytic activity. The prepared Ag/Ar-ZnO exhibits a narrower bandgap of 2.79 eV, highly increased light absorption both in the ultraviolet and visible light regions, and improved charge separation and transfer efficiencies induced by the relatively higher number of oxygen vacancies and the localized surface plasmon resonance (LSPR) effect of the Ag nanoparticles. Therefore, Ag/Ar-ZnO displays a significantly enhanced visible light photocatalytic performance, with a methyl orange (MO) photodegradation rate constant (Kap) that is 2.41 and 3.59 times higher than those of Ag-ZnO and Ar-ZnO, respectively. This research offers an effective way to enhance the photodegradation performance of R-ZnO under visible light irradiation. [ABSTRACT FROM AUTHOR]

In recent years, the utilization of the peracetic acid (PAA)-based advanced oxidation process (AOP) for water treatment has gained significant attention. This is due to its ability to generate highly reactive species such as hydroxyl radicals (˙OH) and organic oxygen radicals (R-O˙), which efficiently degrade organic pollutants in water. However, traditional activation methods involving ultraviolet radiation, heat, and transition metal ions have limitations in terms of efficiency, control, and potential metal sludge production. To address these challenges, a novel heterogeneous PAA-based AOP process utilizing the HOF-Cu-g-C3N4 catalyst was developed for high-performance antibiotic removal. This approach effectively coordinates the reaction interfaces, activation sites, and light energy harvesting for enhanced activity and sustainability. X-ray photoelectron spectroscopy (XPS) analysis of HOF-Cu-g-C3N4 indicated that heterogeneous catalysis occurred at two different active sites on the catalyst's surface. The analysis also revealed that the presence of hydroxyl radicals (˙OH) and organic radicals (such as CH3C(O)O˙ and CH3C(O)OO˙) played a significant role in the generation of free radicals in the PAA system. These free radicals were found to dominate the oxidative degradation of antibiotics. The degradation of antibiotics was observed to be effective over a wide pH range, especially at near-neutral pH. Interestingly, the addition of Cl− ions was found to have a notable promotion effect on the degradation of antibiotics. The electrochemical characterization results and free radical measurement provided evidence for the most plausible free radical mechanism and the Cl− ion boosting mechanism. These findings highlight the environmental applicability and versatility of the HOF-Cu-g-C3N4 catalyst for the advanced treatment of refractory pollutants. [ABSTRACT FROM AUTHOR]

The use of ZnO as a photocatalyst for organics degradation has been reported in the literature, but a divergence of results suggests that surface groups play a critical role in its photoactivity. In this paper, we describe the influence of annealing time on the photoactivity of ZnO particles by analyzing their behavior against molecules with typically high surface adsorption, i.e., methylene blue and rhodamine B. ZnO prepared through the chemical precipitation route at room temperature has been calcined at mild temperatures to gradually eliminate surface –OH groups. Although the increase in annealing time had promoted the crystallite size to increase through the elimination of Zn(OH)2, the particle growth reduced the specific surface area and surface hydroxylation, both of which are critical features concerning photocatalysis. The probing of the main degradation mechanisms evinced that the generation of OH* radicals is the only relevant process for oxidation, which is closely related to the nature of –OH groups. After the complete ZnO crystallization, a balance of morphology, surface area, exposed surface, and surface hydroxylation is necessary to obtain the most efficient materials. [ABSTRACT FROM AUTHOR]

The catalytic properties of metal–organic frameworks (MOFs) containing triangular Fe(III) clusters in the promotion of organic syntheses and photocatalysis applications have been receiving substantial attention for decades. These clusters are appealing due to the strong Lewis acidity afforded by coordinatively unsaturated sites upon the removal of solvent from the framework. In this paper, triangular Fe(III) cluster-based MOFs were shown to be highly efficient heterogeneous catalysts for the solvent-free one-pot condensation of 2-aminobenzamide and alcohols to form quinazolin-4-ones under microwave irradiation. The Fe-MOF catalysts ranging from microporous to mesoporous structures with a variety of geometrical pore structures were investigated. Because of the open accessible spaces for reactants and high density of active sites, MOF-907, built from trimer Fe clusters and a mixture of two linkers, was more effective than other Fe(III)-MOFs. The catalyst can be used for a broad substrate scope and recycled several times without a significant drop-off in its activity. [ABSTRACT FROM AUTHOR]

The rapid recombination of charge carriers in semiconductor-based photocatalysts results in a low photocatalytic activity. Co-catalysis is considered a promising strategy to improve the photocatalytic performance of semiconductors. In this study, a bimetallic phosphide was grown by a facile in situ growth method. Loading the cocatalyst (7 wt% NiCoP) leads to activity enhancement by a factor of approximately 27 times in the visible-light-driven hydrogen evolution relative to the pristine Zn0.5Cd0.5S. The photocatalysis shows a high hydrogen evolution rate of 19.5 mmol g−1 h−1, which is much higher than that of the single metal phosphide (Ni2P: 7.0 mmol g−1 h−1; CoxP: 8.1 mmol g−1 h−1) and 7 wt% Pt modified Zn0.5Cd0.5S (0.3 mmol g−1 h−1). Its apparent quantum efficiency reaches 41.6% at 420 nm. Moreover, the photocatalyst exhibits a remarkable photostability for five consecutive cycles of photocatalytic activity measurements with a total reaction time of 15 hours. The excellent photocatalytic activity of the photocatalyst was attributed to the in situ-formed NiCoP cocatalyst, which not only acts as a reactive site but also accelerates the separation of charge carriers. [ABSTRACT FROM AUTHOR]

The simultaneous upcycling of all components in lignocellulosic biomass and the greenhouse gas CO2 presents an attractive opportunity to synthesise sustainable and valuable chemicals. However, this approach is challenging to realise due to the difficulty of implementing a solution process to convert a robust and complex solid (lignocellulose) together with a barely soluble and stable gas (CO2). Herein, we present the complete oxidative valorisation of lignocellulose coupled to the reduction of low concentration CO2 through a three-stage fractionation–photocatalysis–electrolysis process. Lignocellulose from white birch wood was first pre-treated using an acidic solution to generate predominantly cellulosic- and lignin-based fractions. The solid cellulosic-based fraction was solubilised using cellulase (a cellulose depolymerising enzyme), followed by photocatalytic oxidation to formate with concomitant reduction of CO2 to syngas (a gas mixture of CO and H2) using a phosphonate-containing cobalt(II) bis(terpyridine) catalyst immobilised onto TiO2 nanoparticles. Photocatalysis generated 27.9 ± 2.0 μmolCO gTiO2−1 (TONCO = 2.8 ± 0.2; 16% CO selectivity) and 147.7 ± 12.0 μmolformate gTiO2−1 after 24 h solar light irradiation under 20 vol% CO2 in N2. The soluble lignin-based fraction was oxidised in an electrolyser to the value-added chemicals vanillin (0.62 g kglignin−1) and syringaldehyde (1.65 g kglignin−1) at the anode, while diluted CO2 (20 vol%) was converted to CO (20.5 ± 0.2 μmolCO cm−2 in 4 h) at a Co(II) porphyrin catalyst modified cathode (TONCO = 707 ± 7; 78% CO selectivity) at an applied voltage of −3 V. We thus demonstrate the complete valorisation of solid and a gaseous waste stream in a liquid phase process by combining fractioning, photo- and electrocatalysis using molecular hybrid nanomaterials assembled from earth abundant elements. [ABSTRACT FROM AUTHOR]

Novel two-dimensional (2D) oxides are of great interest for photocatalysis because of their superlative physical features, namely, large surface areas, short charge diffusion pathways, high crystallinity and easy surface modification. However, most 2D oxides suffer from weak visible light absorption and severe photogenerated carrier recombination. Nitrogen doping can successfully narrow the bandgap of 2D oxides but can hardly improve the charge separation. In this work, we pre-dope nitrogen into 2D titanate nanosheets (HTiO), followed by surface processing with solution plasma. By dual modification of nitrogen doping and solution plasma processing (SPP), the modified 2D titanate nanosheets (N-HTiO-SPP) display broad absorption extending to the visible light region and the healing of oxygen vacancies brought about by nitrogen doping. Compared with HTiO and nitrogen doped titanate (N-HTiO), a higher removal rate and mineralization rate towards the photocatalytic degradation of acetaldehyde were achieved over N-HTiO-SPP under solar light. This work provides a powerful way to activate 2D wide bandgap semiconductors for enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

This study introduces a cost-effective methodology to synthesize Ag@MCM-41 composites, utilizing petroleum sludge ash as a precursor. These nanomaterials exhibit well-structured arrangements and hold tremendous promise for applications in both photocatalysis and antimicrobial activities within the context of water treatment. The catalysts were subjected to thorough characterization using techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and scanning electron microscopy (SEM) to assess their structural and optical properties. The XRD analysis corroborated the successful synthesis of orderly nanomaterials, while reflections corresponding to metallic silver planes convincingly demonstrated the effective integration of silver nanoparticles onto the MCM-41 surface, while simultaneously preserving its refined and ordered mesostructure. Subsequently, the photocatalytic performance of the composites was meticulously evaluated, and the results indicated exceptional degradation rates for MB, RhB, and MO dyes, by 15Ag@MCM-41. This degradation kinetic adhered to a pseudo-first-order model. Furthermore, the nanocomposite displayed remarkable photocatalytic stability across three reuse cycles, with a slight reduction in degradation efficiency observed during the third cycle. In addition to their notable photocatalytic attributes, all Ag@MCM-41 ratios demonstrated notable antibacterial activity against S. aureus and E. coli, as substantiated by the presence of an inhibition zone with a diameter of approximately 14 mm and 12 mm respectively. The nanocomposites we have developed in our current study hold significant promise within the realm of water treatment. They have the potential to serve as a low-cost tool for addressing two crucial aspects: the degradation of pollutants, such as dyes, from water effluents, and the inhibition of microorganisms in water systems. [ABSTRACT FROM AUTHOR]

Coordination polymers (CPs) have been widely proven as sacrificial electrode materials for energy storage applications because of their high porosity, specific surface area and tunable structural topology. In this work, a new 2D Cu(II)-based CP, formulated as [Cu2(btc)(μ-Cl)2(H2O)4]n (CP-1) (H3btc = benzene-1,3,5-tricarboxylic acid), fabrication of copper oxide nanoparticles (CuO NPs) and its composite (CuO@CP-1) were successfully synthesized using solvothermal, precipitation and mechanochemical grinding approaches. Single-crystal X-ray analysis authenticated a two-dimensional (2D) layered network of CP-1. Further, CP-1, CuO NPs and composite were characterized by diffraction (Powder-XRD), spectroscopic (FTIR), microscopic (SEM), and thermal (TGA) techniques. The porosity and surface behavior of CP-1 and the composite were demonstrated using BET analyzer. Topological simplification of CP-1 shows a 3-c connected hcb periodic net. The photocatalytic behavior of CP-1 was examined over methyl red (MR) dye in the presence of sunlight and showed a promising degradation efficiency of 96.80%. The electrochemical energy storage properties of CP-1, CuO NPs and composite were investigated using cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) analysis under aqueous 1 M H2SO4 electrolyte. The electrochemical results show better charge storage performance of CP-1 with a specific capacitance of 602.25 F g−1 at 1 A g−1 current density by maintaining a retention of up to 84.51% after 5000 cycles at 10 A g−1 current density. Comparative electrochemical studies reveal that CP-1 is a promising electrode material for energy storage. [ABSTRACT FROM AUTHOR]

The combustion of fossil fuels has brought about serious energy shortages and environmental pollution issues. This study involves the development of green and environment-friendly nonprecious metal photocatalysts with high hydrogen production performance. Hence, a series of CoxSy/Mn0.5Cd0.5S composites was prepared through a simple hydrothermal process. When the loading amount of amorphous CoxSy was 3 wt%, the CoxSy/Mn0.5Cd0.5S composite catalyst showed the best photocatalytic activity under visible light irradiation (λ > 420 nm), giving a hydrogen production rate of 5677.6 µmol g−1 h−1, which is 121.6 times that of pure CdS and 4.8 times that of Mn0.5Cd0.5S. Moreover, the 3 wt%-CoxSy/Mn0.5Cd0.5S catalyst exhibited good photostability. The experimental results demonstrate that the construction of the CoxSy/Mn0.5Cd0.5S heterojunction effectively facilitates the separation of charge carriers, resulting in an enhanced photocatalytic activity. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have great potential for producing photoelectrocatalyzed hydrogen and degrading pollutants, owing to several factors such as high porosity and tunable semiconductor-like properties. Wide band gaps, which restrict their use to only UV light induced reactions, and low efficiencies for the separation of photogenerated charge carriers (electrons and holes) pose significant challenges to the widespread applications of MOFs. In this study, a hierarchical hollow Pt@H-UiO-66-NH2/CdS ternary catalyst was designed and synthesized. The immobilized CdS nanoparticles (NPs) in this catalyst endow the MOF H-UiO-66-NH2 with high visible light absorption ability and the Pt NPs serve as electron sinks to improve charge carrier separation. Furthermore, the hierarchical hollow structure of H-UiO-66-NH2 in the composite contributes to boosting light absorption and shortening the distance for charge transfer. As a proof of principle, Pt@H-UiO-66-NH2/CdS catalyzes methylene blue (MB) degradation with a high rate constant of 1.025 × 10−2 and hydrogen production with a rate of 12 810 μmol g−1 h−1, the latter of which is about 2.3, 11.7 and 173 times higher than those of Pt@UiO-66-NH2/CdS, H-UiO-66-NH2/CdS and Pt@H-UiO-66-NH2, respectively. [ABSTRACT FROM AUTHOR]

Highly efficient 2D/2D layered heterostructure of nickel oxide (NiO) and molybdenum sulphide (MoS2) has been fabricated for the photoelectrochemical (PEC) water splitting and degradation of Bromophenol Blue (BPB) under visible light. The XRD spectra confirm mixed characteristic peaks of MoS2 and NiO in the nanocomposite. SEM displays flower-like patterns of pure and composite material with the 2D nanosheets layer structure. The band gap reduction (2.25–1.72 eV) is due to the incorporation of NiO in MoS2 for visible light harvesting. TEM confirms the homogeneous distribution of 2D/2D nanosheets. The excellent interfacial coupling in strong 2D/2D interactions boost the electro and photocatalytic activities. 15.0% NiO showed excellent PEC activity toward OER with maximum photocurrent density of 1.57 mA cm−2, which influenced the overall water splitting at lower potential, ensuring visible photoresponse. The maximum photodegradation performance for highly toxic BPB was achieved by the photocatalyst, which contains 15.0 wt% NiO in NiO/MoS2 composite. It displays the highest conversion efficiency (∼87.0%) for BPB owing to exposed active sites via Mo–Ni–S linkages. Defects in NiO/MoS2 offer favorable reaction dynamics to PEC OER, which are helpful in tuning the band potentials. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-CN) has versatile applications in photocatalysis because of its structural merits, among which the photodegradation of organic pollutants is important. Nonetheless, the limited specific surface area (SSA) and sluggish mass transfer of g-CN restrict its photocatalytic activity. Herein, g-CN with highly ordered macropores (g-CN-HOM-50) was prepared through a harmless, facile and convenient strategy. The research results showed that highly-ordered macropores are greatly advantageous to the properties of the catalyst. The SSA of g-CN-HOM-50 increased to 2.5 times that of bulk g-CN (BCN) measured by nitrogen adsorption–desorption analysis, the mass flow of single g-CN-HOM-50 was enhanced by 7.9% compared to BCN as confirmed by computational fluid dynamics (CFD) simulations and the apparent rate constant (k) of the rhodamine B (RhB) degradation reaction improved to 3.5 times that of BCN. Moreover, it was found that the highly ordered macropores prominently affect the band structure and significantly improve the production of reactive oxygen species. This work provides a prospective catalyst for photocatalytic waste water purification and a strategy for the modification of g-CN. [ABSTRACT FROM AUTHOR]

This paper reports an environmentally benign, simple, cost efficient, one-step, surfactant free, and biogenic synthesis of a silver–graphene (Ag–graphene) nanocomposite using an electrochemically active biofilm (EAB). The EAB was used for the reduction of Ag+ to Ag0 onto the graphene sheets. The morphology, structure, composition, and optical properties and contact angle of the Ag–graphene were obtained using a range of techniques which confirmed the anchoring/presence of silver nanoparticles (AgNPs) onto the graphene sheets. The photocatalytic activity of Ag–graphene was evaluated by the degradation of methylene blue and Congo red dye in aqueous solution at an ambient temperature in the dark and under visible-light irradiation. The results showed that the photocatalytic activity of the Ag–graphene nanocomposite was enhanced significantly by the loading of AgNPs in the graphene sheets. Contact angle measurements confirm the hydrophilic nature of the Ag–graphene nanocomposite which is very helpful in photocatalysis. The electrical conductivity and photocurrent measurements of the Ag–graphene nanocomposite exhibited a much better performance than P–graphene. This study highlights the design of a novel facile synthetic route for a new photocatalyst using the SPR of Ag and graphene as a support. The as-synthesized Ag–graphene nanocomposite has potential applications in photocatalytic degradation, photoelectrodes and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Adsorption and photocatalysis processes are considered to have high significance for the remediation of toxic dyes in aquatic media. Herein, we report the remarkable performance of uncapped SnO2 quantum dots (QDs) synthesized by varying the drying process. Structure property correlations of the QDs were evaluated by XRD, HRTEM, Raman, PL, FTIR, TGA, BET, and zeta potential techniques. A tailored synthesis process delivered zeta potential values up to −50 mV for QDs dried at a temperature of <60 °C. These QDs were highly selective for the adsorption of methylene blue (MB), and showed 91% adsorption in one minute. The optimum adsorbent concentration of the SnO2 QDs and the pH values for MB removal were found to be 0.3 mg ml−1 and ∼8, respectively. The Raman and FTIR studies revealed the mechanism of adsorption of MB on QDs which occurred through the alkylated nitrogen group of MB with the surface hydroxyl group of the SnO2 QDs. The selective adsorption of MB was demonstrated by using a mixture of cationic MB and anionic methyl orange (MO). The un-adsorbed MO was then completely degraded in less than 15 min by irradiating it with ultraviolet light. Furthermore, the reason for the exclusive adsorption property of these QDs compared to the SnO2 QDs synthesized at a relatively high temperature of 100 °C is also discussed. Thus, the induction of an excellent adsorption property as well as the remarkable photocatalytic degradation ability of the uncapped SnO2 QDs was demonstrated for two carcinogenic pollutant dyes and this will facilitate its use as a novel property in nanomaterials. [ABSTRACT FROM AUTHOR]

Amidst the progress made by the world economy, the textile industry is a huge contributor to economic development. However, the unplanned intrusion of discharge from the industrial effluents that contain toxic chemicals and dyes into bodies of water affects all forms of life in the environment. Thus, water pollution affects the economy in many adverse ways. The primary method for the mitigation of environmental contaminants is semiconductor photocatalysis, which is activated using solar light irradiance. In this article, two-dimensional (2D) rhenium diselenide (ReSe2) transition metal dichalcogenide (TMD) nanosheets (NSs) are synthesized using a simple and environmentally benign low-energy-intensity one-step hydrothermal approach. The synthesized optimized ReSe2 catalyst effectively degrades the organic pollutant rhodamine B (RhB) when exposed to visible-light illumination. It is found that the ratio of the ReSe2 catalyst to the RhB dye plays a decisive role in dictating the efficiency of the as-synthesized ReSe2 catalyst. The findings suggest that the optimized catalyst ReSe2 NSs show enhanced absorptivity of the dye, an extended photoresponse towards the visible domain, and enhanced charge separation and the simultaneous diffusion of the photogenerated electron/hole charge carriers to the catalyst surface. The best photocatalytic activity observed for a 4 mg/5 ml catalyst-to-dye loading ratio, resulting in a photocatalytic degradation efficiency of 87.3% for the RhB dye under visible-light illumination, which has rarely been reported for other 2D TMDs. Moreover, the optimized catalyst retains its stability during each of four consecutive cycles of dye degradation. The mechanism of photocatalysis was examined through a reactive trapping experiment. The results show that superoxide radicals and holes are the main reactive species in the photocatalytic reaction. This study was supported by the characterization tools of Raman spectroscopy, UV-Vis absorbance, XRD, TEM, SEM and XPS. Overall, with the goal of balancing aquatic ecosystems, this planned effort offers a potential remedy for the breakdown of organic contaminants under visible-light illumination. [ABSTRACT FROM AUTHOR]

Tailoring the surface properties of catalysts by introducing various functional groups with superior adsorption properties has been a promising strategy to boost photocatalytic performance. In this study, the thermal exfoliation of graphitic carbon nitride (g-C3N4) was utilized to produce ultrathin nanosheets that exhibit a high specific surface area and abundant active sites. The exfoliated g-C3N4 nanosheets (CN-600) were produced by heating pristine g-C3N4 (CN) in ambient air at 600 °C for 2 hours, and exhibit a specific surface area of 171.05 m2 g−1, and a higher quantity of functional groups (–NH2 and oxygen). The morphological analysis demonstrates exfoliated nanosheets (average thickness ∼1.44 nm) with curly edges and fluffy structures. XPS analysis estimates the surface atomic ratio (C/N) as 0.988 and 0.758 for CN and CN-600, respectively, confirming lower structural flaws of the latter. CN-600 demonstrates a noteworthy improvement in its ability to degrade multiple pollutants and antibiotics in diverse aqueous solutions, showcasing its superior photocatalytic activity under solar radiation. CN-600 exhibits a higher rate constant than pristine CN by 3.66, 7.01, and 1.42 times, respectively, in the degradation of methylene blue, rhodamine B, and ciprofloxacin. This enhancement in photocatalytic performance is corroborated by a larger specific surface area of the nanosheets, an abundance of active sites, a higher number of functional groups (–NH2 and oxygen), and a reduced distance of charge transfer between the layers. Overall, the g-C3N4 nanosheets exhibit significant potential as a high-performance photocatalytic material that operates efficiently with visible light, offering a plethora of possible applications in the fields of energy and the environment. [ABSTRACT FROM AUTHOR]

Visible light-mediated catalysis has gradually become an important means of green catalytic organic synthesis. However, traditional photosensitizers (organic dyes or precious transition metal complexes, for instance) have limited applications due to their inherent toxicity and non-reusability. A β-ketoenamine-linked covalent organic framework (TAPT-TP-COF), as a heterogeneous photocatalyst, was synthesized by solvothermal reaction and characterized by FT-IR, XPS, SEM, TEM, XRD, BET and optical performance tests. The TAPT-TP-COF exhibited favorable photocatalytic activity, remarkable substrate scope and recyclability performance for the synthesis of 2-arylbenzothiazoles by the intramolecular cyclization reaction of N-arylbenzothioamides. This research provides a new solution for the cyclization reaction in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

In this paper, we present the first report on an organic conducting polymer film, which alone exhibits both superhydrophobicity and visible light photoactivity. The microstructure of poly(3-hexylthiophene) was optimized using controlled precipitation until superhydrophobic behavior was achieved. Photocatalytic tests employing visible light irradiation proved that polymer degrades the ethanol test molecule. [ABSTRACT FROM AUTHOR]

This paper presents a facile one-step approach for the syntheses of MoS2/GC (GC = graphitic carbon) with sodium alginate as the biomass carbon source. The MoS2/GC composites showed enhanced photocatalytic activity for degradation of methylene blue under visible light irradiation. The MoS2/GC (2 : 1) composite shows the best performance and 99.2% methylene blue can be removed in 100 minutes. GC plays an important role in the fast separation and transfer of photogenerated charges across interfaces. The activity and stability performances suggest that the MoS2/GC composite has great potential for practical industrial wastewater treatment. [ABSTRACT FROM AUTHOR]