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The design, synthesis, and photoelectrochemical characterization of Co3(PO4)2, a hydrogen evolving catalyst modified with reduced graphene oxide (RGO), is reported. The 3 D flowerlike Co3(PO4)2 heterojunction system, consisting of 3 D flowerlike Co3(PO4)2 and RGO sheets, was synthesized by a one-pot in situ photoassisted method under visible-light irradiation, which was achieved without the addition of surfactant or a structure-directing reagent. For the first time, Co3(PO4)2 is demonstrated to act as a hydrogen evolving catalyst rather than being used as an oxygen evolving photoanode. In particular, 3 D flowerlike Co3(PO4)2 anchored to RGO nanosheets is shown to possess dramatically improved photocatalytic activity. This enhanced photoactivity is mainly due to the staggered type II heterojunction system, in which photoinduced electrons from 3 D flowerlike Co3(PO4)2 transfer to the RGO sheets and result in decreased charge recombination, as evidenced by photoluminescence spectroscopy. The band gap of Co3(PO4)2 was calculated to be 2.35 eV by the Kubelka-Munk method. Again, the Co3(PO4)2 semiconductor displays n-type behavior, as observed from Mott-Schottky measurements. These RGO-Co3(PO4)2 conjugates are active in the visible range of solar light for water splitting and textile dye degradation, and can be used towards the development of greener and cheaper photocatalysts by exploiting solar light. [ABSTRACT FROM AUTHOR]

A visible light driven, direct Z-scheme reduced graphene oxide-Ag3PO4 (RGO-Ag3PO4) heterostructure was synthesized by means of a simple one-pot photoreduction route by varying the amount of RGO under visible light illumination. The reduction of graphene oxide (GO) and growth of Ag3PO4 took place simultaneously. The effect of the amount of RGO on the textural properties and photocatalytic activity of the heterostructure was investigated under visible light illumination. Furthermore, total organic carbon (TOC) analysis confirmed 97.1 % mineralization of organic dyes over RGO-Ag3PO4 in just five minutes under visible-light illumination. The use of different quenchers in the photomineralization suggested the presence of hydroxyl radicals ( .OH), superoxide radicals ( .O2−), and holes (h+), which play a significant role in the mineralization of organic dyes. In addition to that, clean hydrogen fuel generation was also observed with excellent reusability. The 4 RGO-Ag3PO4 heterostructure has a high H2 evolution rate of 3690 μmol h−1 g−1, which is 6.15 times higher than that of RGO. [ABSTRACT FROM AUTHOR]

Weak photon absorption and fast carrier kinetics in graphene restrict its applications in photosensitive reactions. Such restrictions/limitations can be overcome by covalent coupling of another photosensitive nanostructure to graphene, forming graphene-semiconductor nanocomposites. Herein, we report one-pot synthesis of RGO- Ag3 VO4 nanocomposites using various sacrificial agents like ethanol, methanol, propanol and ethylene glycol ( EG) under visible light illumination. The Raman spectral analysis and 13C MAS NMR suggest ethanol to be the best sacrificial agent among those studied. Thermal analysis studies, further, confirm the stability of the synthesized nanocomposite with ethanol as sacrificial agent. In view of this, the activity toward dye degradation was focused over the composites prepared via ethanol as sacrificial agent. It was observed and proved that cationic dyes could be degraded quantitatively and swiftly compared to anionic dyes (37.79%) in 1.5 h. This suggests that the surface of the nanocomposites is anionic as partial reduction takes place during synthesis process. In case of mixed dye degradation process, it was noticed that the presence of cationic dye doubles the degradation of anionic dye. The activity of these synthesized nanocomposites is more than five-fold toward the phototransformation of phenol and photodegradation of textile dyes under visible light illumination. [ABSTRACT FROM AUTHOR]

Highlights This work investigates the construction of biodegradable packaging film based on polylactic acid (PLA) reinforced with a novel antibacterial hybrid nanofiller to improve barrier and mechanical properties. The study focuses on incorporating silver‐ingrained silica particles (Ag–In–Si) into PLA matrix to prepare the packaging film (Ag–In–SiPLA) that has superior antibacterial, and barrier property with negligible oxygen and water vapour penetration. The Ag was synthesized using natural neem leaf extract as a reducing agent. To ingrain silver over rice husk silica (Si) an in situ technique was adopted. Hence called Ag‐In‐Si bio‐filler. The Ag–In–SiPLA films were fabricated using melt blending and sheet extrusion methods by means of a micro‐compounder. The addition of rice husk silica served the purpose of cost‐effectiveness of the packaging film along with the enhancement of the oxygen and water barrier properties of the films. The optimized sample (PLA loaded with 3% Ag–In–Si), exhibited optimum transparency, moisture resistance, and barrier properties compared with control PLA film. The experiments on Muntingia calabura (Jamaica cherry) preservation have verified the remarkable effectiveness of Ag–In–SiPLA films in preserving their quality for an extended period. These biodegradable packaging films, composed of food‐grade materials and sustainable ingredients, have the potential to provide a compostable and environmentally friendly solution for various packaging applications. This research shed light on the antibacterial Ag–In–SiPLA film as a long‐term, high‐performance fruit packaging solution. Novel antibacterial PLA composite with enhanced barrier and mechanical properties. Silver‐ingrained silica particles improve antibacterial and barrier properties. Green synthesis of silver using neem leaf extract Melt blending and sheet extrusion used to create cost‐effective packaging films. Ag–In–SiPLA films extend Muntingia calabura preservation, proving effective. [ABSTRACT FROM AUTHOR]

This study demonstrated the effectiveness of poly meta-aminophenol (PmAP) as a solid electron mediator in the Z-scheme photocatalytic system for organic pollutants (viz. bisphenol-A and reactive dyes) mineralization and also illustrated how PmAP transported the photogenerated electrons from an O 2 -emitting photocatalyst (Ag 3 PO 4 ) to a H 2 -emitting photocatalyst (CoFe 2 O 4 ) enabling enhanced photocatalytic activity under visible light irradiation. The PmAP/Ag 3 PO 4 -CoFe 2 O 4 (PAC-10), was prepared by a two-step process and characterized by various analytical methods to assess the impact of PmAP on optical, photocatalytic, and electrochemical characteristics of the CoFe 2 O 4 (CFO)/Ag 3 PO 4 composite. The morphological investigation revealed that the PmAP sheet was nicely decorated with evenly distributed Ag 3 PO 4 and CoFe 2 O 4 particles. The M-S plot and impedance analyses were used to assess the electrochemical capabilities of the catalyst. Z-scheme charge transfer pathways were well supported by the radical trapping experiment and HRTEM analysis of Pt photodeposited PAC-10 photocatalysts during the photoreaction. Because of its magnetic nature and ease of synthesis, the PAC-10 offers an easily recyclable Z-scheme photocatalytic system that has the potential for purifying wastewater with high concentrations (up to 100 mg/L) of organic pollutants within 30 min of visible light exposition., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The design, synthesis, and photoelectrochemical characterization of Co 3 (PO 4 ) 2 , a hydrogen evolving catalyst modified with reduced graphene oxide (RGO), is reported. The 3 D flowerlike Co 3 (PO 4 ) 2 heterojunction system, consisting of 3 D flowerlike Co 3 (PO 4 ) 2 and RGO sheets, was synthesized by a one-pot in situ photoassisted method under visible-light irradiation, which was achieved without the addition of surfactant or a structure-directing reagent. For the first time, Co 3 (PO 4 ) 2 is demonstrated to act as a hydrogen evolving catalyst rather than being used as an oxygen evolving photoanode. In particular, 3 D flowerlike Co 3 (PO 4 ) 2 anchored to RGO nanosheets is shown to possess dramatically improved photocatalytic activity. This enhanced photoactivity is mainly due to the staggered type II heterojunction system, in which photoinduced electrons from 3 D flowerlike Co 3 (PO 4 ) 2 transfer to the RGO sheets and result in decreased charge recombination, as evidenced by photoluminescence spectroscopy. The band gap of Co 3 (PO 4 ) 2 was calculated to be 2.35 eV by the Kubelka-Munk method. Again, the Co 3 (PO 4 ) 2 semiconductor displays n-type behavior, as observed from Mott-Schottky measurements. These RGO-Co 3 (PO 4 ) 2 conjugates are active in the visible range of solar light for water splitting and textile dye degradation, and can be used towards the development of greener and cheaper photocatalysts by exploiting solar light., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)