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In the contemporary era marked by pressing environmental and energy challenges, there is a growing imperative to create effective and eco-friendly approaches to combat pollution and promote the generation of clean and green energy. One such strategy that has attracted much interest recently is the photocatalytic generation of green energy and pollutant removal. Numerous photocatalysts have been created to treat water and generate clean energy. Zn-Ti LDH materials are two-dimensional materials that have unique physical and chemical properties, making them promising photocatalysts. Zn-Ti LDHs have a distinctive layered structure that makes them extremely adaptable for photocatalytic applications. This structure also provides large surface areas, customisable compositions, and abundant active sites. However, Zn–Ti LDH has a low solar energy efficiency because it is primarily triggered by ultraviolet light, which makes up around 5% of sunshine. Therefore, this investigation aims to provide a thorough summary of the latest advancements in the modification of the materials based on Zinc-Titanium Layered Double Hydroxides (Zn-Ti LDHs) for a broad spectrum of photocatalytic uses. This study also covers the fabrication methods for Zn-Ti LDHs and the creation of heterojunctions and composites based on Zn-Ti LDHs. Additionally, it delves into the mechanisms underlying the degradation of pollutants and the generation of clean energy. We have highlighted the potential for new prospects, existing challenges, and progress in this context. [Display omitted] • Fabrication and photocatalytic mechanisms of Zn-Ti LDH based materials for environmental solutions. • Latest advancements in heterojunctions and composites utilizing Zn-Ti LDH for applications in photocatalysis. • Various approaches for enhancing the photocatalytic capabilities of Zn-Ti LDH are explored. • The summary, challenges, and future outlook are all addressed. [ABSTRACT FROM AUTHOR]

Since the growing need for fuel is causing major harm to the environment, it is essential to introduce photocatalytic energy conversion devices that are safe for the environment. One such strategy is the utilisation of photocatalytic water-splitting devices to achieve sustainable hydrogen production. In order for these devices to operate optimally, it is imperative to utilise materials that possess the capability to properly capture sunlight. Porphyrins are significant molecules that can be found all over nature as units that absorb visible light. Energy conversion devices can benefit from porphyrins' multifunctional features, including their easy fabrication, excellent chemical constancy, plentiful metallic active sites, adaptable crystalline structure, and high specific surface area. They can produce charge-transfer excited states with or without a cocatalyst and make it easier to transfer energy and move rapid excited energy. These properties, along with their ease of synthesis, make them excellent starting materials for porous metal-organic framework-based photocatalysts that convert solar energy into usable fuels. This article provides an overview of the synthesis as well as designing of porphyrin-based MOFs. The effect of metal in porphyrin besed MOFs and two bridging ligands are summarized briefly. In this article, the photocatalytic applications of porpyrin based MOFs and composites as photocatalysts, such as the hydrogen evolution process and photodegradation of organic contaminants are discussed. In conclusion, the bottlenecks that need to be overcome and some potential solutions for the ongoing research and development of porphyrin-based MOF photocatalysts are discussed. [Display omitted] • Porphyrin-based MOFs as photo-active materials for photocatalysis are discussed. • Synthesis strategies for Porphyrin MOF composite photocatalysts are discussed. • Comprehensive breakdown of various bridging ligand types is provided. • Strategies for boosting photocatalytic performance are summarized. • Advances for H 2 evolution and water treatment research hotspots are summarized. [ABSTRACT FROM AUTHOR]

Significant ecosystem damage and severe environmental issues have surfaced due to unplanned exploitation of resources and industrial expansion. The water bodies are continuously polluted by numerous organic dyes released from industrial effluents. In this work, we report construction of new g-C 3 N 5 /Bi 24 O 31 Br 10 S-scheme heterojunction for UV–visible light driven superior organic dye degradation. The integrated heterojunction with high interfacial charge transfer exhibited excellent 99.08% (∼100%) within 60 min exposure which is manifolds higher than bare g-C 3 N 5 and Bi 24 O 31 Br 10. The mechanistic investigations showed that the key active radicals in photocatalytic CV degradation are the •O 2 - and h+. Building an S-scheme model with favourable energy band structure encourages efficient separation of charges while maintaining the inherent redox capacity of the g-C 3 N 5 /Bi 24 O 31 Br 10 catalyst, which is highly beneficial for superior photocatalytic performance. This work offers a fresh viewpoint for creating organic-inorganic hybrid new S-scheme heterojunctions for high performance photocatalytic waste-water treatment. • High efficiency 2D–2D g-C 3 N 5 /Bi 24 O 31 Br 10 S-scheme heterojunction was designed. • Catalyst exhibit excellent degradation efficiency of 99.08% for CV removal. • PL suggests the efficient charge separation of the carriers. • ·O 2 - and h+ are responsible for CV degradation. [ABSTRACT FROM AUTHOR]

The reasonable designing, interfacial tuning and construction of S-scheme heterostructures offering high performance water pollutants treatment and energy production still remains challenging. Following the structure, band structure and interface function perspective, we prepared Fe 7 S 8 /CuIn 5 S 8 heterostructures photocatalysts with sulfur vacancies for superior norfloxacin (NOR) degradation and hydrogen production under visible light. In particular, for optimal 30FS/CIS (30%Fe 7 S 8 /CuIn 5 S 8), the H 2 evolution was up to 35.6 mmol g−1 h−1 which was 11.5 times than pristine Fe 7 S 8 with TEOA as sacrificial agent. The heterojunction could also show 98.7% degradation of NOR in 90 min under visible light. Interestingly, using NOR pollutant as sacrificial agent under synergistic conditions, 22.7 mmol g−1 h−1 H 2 evolution and 98.9% degradation of NOR (in 45 min) was achieved. The significantly boosted photocatalytic pollutant degradation and hydrogen generation performance over Fe 7 S 8 /CuIn 5 S 8 hybrids is ascribed to the efficient S-scheme charge transfer and active sites provided by sulfur vacancies (V s). The deep electron transfer mechanism and the charge transfer efficiency were supported by in-situ XPS, UPS, electrochemical experiments and photoluminescence. Experimental results including scavenging tests and ESR findings provided the direct evidence of photogenerated holes and ●OH radicals for pollutant degradation and electrons in hydrogen generation. This work contributes to effective designing and developing high-activity visible light/solar light assisted heterojunction photocatalysts for realizing superior clean energy generation and pollutant degradation. [Display omitted] • Novel S-scheme Fe 7 S 8 /CuIn 5 S 8 heterostructures successfully constructed. • Synchronous norfloxacin degradation and hydrogen evolution are realized. • The sulfur vacancies promote separation and light absorption. • The photogenerated holes/●OH and electrons are utilized for pollutant degradation and H 2 production. • The photocatalytic mechanism of H 2 evolution and NOR degradation were proposed. [ABSTRACT FROM AUTHOR]

• Mg 0.5 Ni x Zn 0.5-x Fe 2 O 4 spinel ferrite photocatalyst prepared by facile route. • Dopant driven band shifting- Higher potential for O 2 − generation. • Excellent photo-degradation of RB-19 dye under visible and solar light. • Higher migration and reduced recombination-Role of dopant and redox cycles. • Photocatalytic mechanism and degradation route predicted. Focussing on visible light active ferrites for high performance removal of noxious pollutants, we report the synthesis of Mg 0.5 Ni x Zn 0.5-x Fe 2 O 4 (x = 0.1, 0.2, 0.3, 0.4, & 0.5) ferrite nanoparticle for degradation of reactive blue-19 (RB-19). Lattice parameters calculated using intense X-ray diffraction (XRD) peaks and Nelson-Riley plots (N-R plot) are in well agreement with each other. The sample Mg 0.5 Ni 0.4 Zn 0.1 Fe 2 O 4 (M5N4) exhibits best performance with 99.5% RB-19 degradation in 90 min under visible light. Photoluminescence (PL) results confirm that recombination of charge carriers is highly reduced in the photocatalyst. Scavenging experiments suggest that O 2 − radicals were the dominant species responsible for photocatalytic performance. The photocatalytic mechanism was explained in terms of dopant driven shifting of conduction bands and valence bands (calculated by Mott-Schottky plots). The thermodynamic probability of radical generation along with role of redox cycles of metal ions has been discussed in the mechanism. The dye degradation was ascertained by detection of intermediates via mass spectrometry analysis and a possible degradation route was also predicted. The findings in this work provide intriguing opportunities to modify the electronic band structure of spinel ferrites for visible and solar light photocatalytic activity for environmental detoxification. [ABSTRACT FROM AUTHOR]

In recent times cost-effective advanced materials with dual applications in photocatalytic water treatment and electrochemical sensing have been explored and developed. Herein we report facile solution combustion synthesis of ZnO/Fe 2 O 3 (ZF) type-II heterojunction for electrochemical sensing of dopamine and visible assisted photocatalytic reduction of carcinogenic Cr(VI) into Cr(III). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to evaluate the compatibility of the electrodes for DA sensing. Furthermore, DPV curves revealed that ZF2 (ZnO: Fe 2 O 3 - 3:0.5) modified GCEs possessed 0.27 μM and 0.7 μM of LOD and LOQ with good linear range from 3 μM to 30 μM. Overall, reproducibility and interference studies confirm the efficient use of material for DA sensing. The junction ZF2 shows best performance with 88% Cr(VI) photo-reduction under visible light in 90 min and 100% reduction with tartaric acid as sacrificial agent (utilizing holes) in just 45 min. The effect of sacrificial agents and scavengers suggest the photogenerated electrons were major active species followed by ●O 2 −. The CB edges have enough potential for rapid reduction of hexavalent chromium under visible light and solar light. The photoluminescence and electrochemical impedance suggest lowered recombination, high charge separation and charge transfer capacity in the heterojunction. The transfer of electrons from conduction band of Fe 2 O 3 to that of ZnO having high enough negative potential to reduce Cr(VI), thus utilizing the CB potential of wide band gap ZnO for rapid visible photocatalysis. In addition shortcomings as low conductivity Fe 2 O 3 and high band gap of ZnO are both minimized in the junction. This study confirmed that popular semiconductors as ZnO and Fe 2 O 3 have enough potential in dual role as electrochemical sensors and visible photocatalysts with best performance by optimizing the conditions and ratios. Image 1 [ABSTRACT FROM AUTHOR]

Growing industrialization and urbanization generate greater quantities of wastewater, which is constantly thrown into the surroundings. A number of dangerous contaminants like heavy metals, dyes, pesticides, antibiotics, and microbes are discharged into aquatic environments. Around the world, more than 80% of wastewater is discharged into the environment without being adequately treated. While environmental pollution is still increasing because of the increased percentage of polluting sectors, traditional methods of cleaning the environment are ineffective and costly. Recently, research has concentrated on designing 2D nanomaterials for environmental applications. MXenes and MXene based materials have drawn considerable interest and are now being investigated as novel substrate materials for a variety of applications because of their tuneable interlayer spacing and tailorable surface chemistry. This review discusses the fabrication methods, characterization methods, MXene derived materials, functionalization, toxicity, the multifunctional role of MXene, and applications of MXene based materials for CO 2 reduction, H 2 generation, and wastewater treatment systems. There are also multiple viewpoints on issues and future studies in this field that are addressed. [Display omitted] • The advance of MXene-based nanomaterials for water decontamination and energy conversion application are summarized. • The toxicity, multifunctional role, and fabrication of MXene based materials are introduced. • The reduction of CO 2 and H 2 generation is explained. • The elimination of heavy metals, dyes, antibiotic, and pesticides are determined. [ABSTRACT FROM AUTHOR]

To address the global energy crisis and widespread environmental deterioration issues, semiconductor photocatalysts have been widely recognized and studied. In this direction, new-age materials as zeolitic imidazolate frameworks (ZIFs), belonging to a sub-class of metal-organic frameworks (MOFs) have piqued the interest of researchers as prospective photocatalyst candidates. With huge specific surface area, tuneable porosity, diverse structure, ease of designing and controllable properties, ZIFs are highly sought-after material for pollutant degradation and clean energy generation. Additionally, ZIFs may undergo thermal processing to produce functional substances with similar structural characteristics but improved light responsiveness and electron transfer abilities. Numerous functional materials and better photocatalysts can be prepared by thermal treatment of ZIFs, formation of composites, heterostructures with other semiconductors or electron mediators which may have similar structural characteristics but better light capture abilities, charge transfer capabilities and strong redox properties. This paper carefully summarizes and analyses the applications of ZIFs based photocatalysts for photocatalytic organic pollutant degradation, hydrogen generation and CO 2 conversion. A sincere attempt has been made to lay down mechanistic insights into synergism of the structural and electronic properties of ZIFs with other catalyst counterparts for superior photocatalytic performance with focus on band structure analysis, charge transfer mechanisms and performance. Finally, the achievements, novelties and bottlenecks have been discussed and future research directions have been proposed. [Display omitted] • ZIFs as photocatalytic materials-Special structure and properties. • Synthetic routes to ZIFs based composites and heterojunctions. • Applications for CO 2 reduction, H 2 evolution and water treatment. • Detailed discussion on synergism with semiconductors and mechanisms. • Challenges, opportunities and future prospects were fully debated. [ABSTRACT FROM AUTHOR]

Currently, the photocatalytic nanomaterials performing under solar radiation have gained worldwide attentions due to increasing environmental deterioration. For utilizing the sunlight for degradation of emerging pollutants it is important to develop visible active photocatalysts. This laboratory scale work reports magnetic and optically active nano-photocatalyst Fe x Zn 1−x O(x = 0.01, 0.03, 0.05) synthesized by solution combustion method. High resolution transmission microscopy suggests a slight degradation in the crystallite structure with Fe doping. X-ray photoelectron spectroscopy analysis shows the presence of intrinsic defects in the crystal structure. Zn resides in +2 and and Fe in +3 oxidation state. Optical band gap studies were made with band structure for each doped sample. The photoctalytic activity of the samples was tested by solar degradation of noxious pollutant Bisphenol A. 99.1% of bisphenol was degraded in 90min in presence of Fe 0.03 Zn 0.97 O under synergistic adsorption and photocatalysis. The results were analyzed in terms of total organic carbon, chemical oxygen demand, effect of scavengers, gas chromatography-mass spectrometry and reusability. In presence of Fe 0.03 Zn 0.97 O, 45.3% of total organic carbon was removed and chemical oxygen demand was reduced to 11.2%. A possible mechanism with structures of the intermediates has been given. Effect of scavengers reveal that hydroxyl radicals are major reactive oxygen species involved which is also supported by the band edge positions. The research work promises to design highly photo-active tuneable magnetic photocatalysts for solar powered degradation of contaminants of emerging concern with a simple and cost-effective approach. [ABSTRACT FROM AUTHOR]

In this paper, we report the fabrication and systematic characterization of Fe Doped ZnO thin Films. Fe x Zn 1− x O ( x =0<0.05) films were prepared by RF magnetron sputtering on Si (400) substrate. Influence of Fe doping on structural, optical and magnetic properties has been studied. The X-ray diffraction (XRD) analysis shows that Fe doping has affected the crystalline structure, grain size and strain in the thin films. The best crystalline structure is obtained for 3% Fe Doping as observed from Atomic Force Microscopy (AFM) and X-ray diffraction (XRD). The magnetic properties studied using Vibrating Sample Magnetometer reveals the room temperature ferromagnetic nature of the thin films. However, changing the Fe concentration degrades the magnetic property in turn. The mechanism behind the above results has been discussed minutely in this paper. [ABSTRACT FROM AUTHOR]

We evaluated the diagnostic accuracy of activin B in discriminating tubal ectopic pregnancy (tEP) from intrauterine miscarriages (IUM), and normal viable intrauterine pregnancy (IUP). We included 28 women with tEP, 31 women with IUM, and 29 normal IUP, confirmed both by clinical examination and ultrasonography. Serum activin B concentration was measured at the time of admission using the ELISA kit. The median serum activin B concentration was found to be significantly decreased in both tEP (p = 0.004) and IUM (p = 0.022) compared to normal IUP. When compared between tEP and IUM, activin B concentrations did not differ significantly. ROC analysis of activin B and free β-hCG demonstrated AUC of 0.722 and 0.805, respectively to discriminate tEP from viable IUP. The model including both activin B and free β-hCG improved the discriminating potential with greater AUC (0.824), and specificity (93%) than individual one. To discriminate tEP from IUM, activin B, free β-hCG and combination of both performed poorly. We conclude that serum activin B concentration is lower in tubal ectopic pregnancy, and can discriminate it from normal pregnancy with moderate accuracy. It also shows improved diagnostic potential along with free β-hCG, but cannot distinguish tEP from IUM reliably. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fe doped ZnO nanoparticles have been successfully synthesized by simple sol–gel route. [•] Solubility limit of Fe in ZnO matrix is found to be less than 5%. [•] Fe doped ZnO nanoparticles are better photocatalytic activist than ZnO. [•] Prepared particles possess intrinsic room temperature ferromagnetism. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fundamentals of phosphorene (PN) and graphdiyne (GDY) are briefly discussed. • Structure, fabrication routes and modification strategies. • Advances in PN and GDY based heterostructures for photocatalytic hydrogen evolution. • Environment stability, challenges and future perspectives. Hydrogen evolution from water splitting using semiconductor photocatalysis is regarded as a sustainable and clean energy solution. Among various new age materials, the two-dimensional (2D) monoelemental materials as graphdiyne (GDY) and phosphorene (PN) showing excellent performance owing to their 2D atomic structure and unique properties, have drawn considerable attention. Graphdiyne (GDY) is a two-dimensional carbon-based compound having sp and sp2 hybridized carbon, diacetylene linkage, triangular holes framework and customizable band gap. Different stacking arrangements and homogenous pores in GDY can produce electronic characteristics, opening the door to intriguing energy applications. On the other hand, phosphorene derived from black phosphorous (BP) exhibits strong hole mobility, a variable band gap and broad optical absorption spectrum. With a significant increase in photo-excited charge-separation efficacy, the development of heterostructured photocatalysts driven by BP/PN and GDY has recently become the subject of study in photocatalysis. The recent advancements in development of phosphorene and graphdiyne and their accompanying heterostructured photocatalysts is outlined here, along with their structure, characteristics, synthetic routes and photocatalytic applications. In addition, the photocatalytic applications of PN and GDY based composites and heterostructures have been reviewed and summarised for photocatalytic hydrogen evolution through water splitting. Environmental stability of these heterostructured photocatalysts and the difficulties they pose have been thoroughly investigated for their more effective and extensive uses in the future. [ABSTRACT FROM AUTHOR]

In pursuit of advancing photocatalysts for superior performance in water treatment and clean energy generation, researchers are increasingly focusing on layered double hydroxides (LDHs) which have garnered significant attention due to their customizable properties, morphologies, distinctive 2D layered structure and flexible options for modifying anions and cations. No review has previously delved specifically into ZnCr and NiCr LDH-based photocatalysts and therefore, this review highlights the recent surge in ZnCr and NiCr-based LDHs as potential photocatalysts for their applications in water purification and renewable energy generation. The structural and fundamental characteristics of layered double hydroxides and especially ZnCr-LDHs and NiCr-LDHs are outlined. Further, the various synthesis techniques for the preparation of ZnCr-LDHs, NiCr-LDHs and their composite and heterostructure materials have been briefly discussed. The applicability of ZnCr-LDH and NiCr-LDH based photocatalysts in tackling significant issues in water treatment and sustainable energy generation is the main emphasis of this review. It focuses on photocatalytic degradation of organic pollutants in wastewater, elucidating the principles and advancements for enhancing the efficiency of these materials. It also explores their role in H 2 production through water splitting, conversion of CO 2 into valuable fuels and NH 3 synthesis from N 2 , shedding light on their potential for clean energy solutions. The insights presented herein offer valuable guidance for researchers working towards sustainable solutions for environmental remediation and renewable energy generation. [Display omitted] • Fundamentals and properties of Layered Double Hydroxides (LDHs). • ZnCr and NiCr LDHs as photocatalysts-Properties and Performance. • Water treatment and clean energy production-Mechanism and issues. • ZnCr and NiCr LDH based water treatment & clean energy production. • The challenges and future development direction for sustainable use are discussed. [ABSTRACT FROM AUTHOR]

Microplastics (MPs), as emerging pollutants, have attracted the attention of environmentalists, statespersons, and the scientific community over the last few decades. To address the spread of MPs in the environment, it is imperative to develop various removal techniques and materials that are effective, scalable, and ecologically benign. However, to the best of our knowledge, no review has systematically examined the removal of MPs using adsorption or provided an in-depth discussion on various adsorbents. Adsorption is an inexpensive and effective technology for wastewater treatment. Recently, many researchers have conducted studies on MP remediation using diverse adsorbent materials, such as biochar, activated carbon, sponges, carbon nanotubes, metal-layered oxides, metal-organic frameworks (MOFs), and zeolites. Each adsorbent has advantages and disadvantages. To overcome their disadvantages, researchers have been designing and developing hybrid adsorbents for MP remediation. This review provides insights into these individual adsorbents and also discusses hybrid adsorbents for MP removal. Finally, the review elaborates on future possibilities and ways to enable more efficient, scalable, and environmentally friendly MP cleanup. Overall, this review bridges the gap between contemporary MP remediation using adsorption techniques and adsorbent development. [Display omitted] • Adsorption-based microplastic remediation was reviewed. • The factors affecting microplastic adsorption were thoroughly discussed. • A comprehensive analysis is presented on several microplastic adsorbents. • Microplastic adsorption challenges and future perspectives are examined. [ABSTRACT FROM AUTHOR]