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The dominance of plastics in the packaging market is due to their low weight and thickness, which save transportation costs. However, their non-biodegradability poses a significant threat to the environment. Paper, on the other hand, is considered as a safer alternative due to its natural composition and biodegradability. The porous structure of paper limits its application in packaging, and its poor water resistance further restricts its use in humid environments. Therefore, lamination is a method useful tool to improve the barrier properties of paper. Additionally, the researchers are focusing on developing biodegradable and water-based coatings with anti-fat properties as a green alternative to plastic packaging. The impact of a new grease-resistant coating composed of starch, gelatin and sodium alginate on the mechanical properties of paper was investigated through tensile, tearing, and bursting strength tests. The results showed significant improvements in the mechanical properties of the coated paper sheets. Furthermore, the biodegradability test indicated that the paper samples coated with the new composition showed a 50% weight loss after one week of incubation in the soil, and after three weeks, they exhibited 100% weight loss, demonstrating their outstanding biodegradability. [ABSTRACT FROM AUTHOR]

• Facile vacuum-assisted filtration method was used to assemble ERGO/MoS 2 -based films. • USER reaction quickly expanded the structure of graphene oxide-based films. • The most electrochemically active film was with the ratio 1:1 of ERGO to ex-MoS 2. • The displayed discharge capacity of ERGO/MoS 2 –1 (ratio 1:1) is 916 mAh/g. • Reduced graphene oxide-based films electrodes do not utilize non-active materials. In this paper, thin free standing films based on ultrafast self-expanded reduced graphene oxide (ERGO) and exfoliated molybdenum disulfide (ex-MoS 2) were prepared via vacuum-assisted filtration and tested as anodes in Li-ion half-cells. Three films with GO to ex-MoS 2 ratio of 1:1, 1:2 and 2:1 were assembled (ERGO/MoS 2 –1, ERGO/MoS 2 –2, ERGO/MoS 2 –3, respectively). Reduction of GO-based films was conducted via ultrafast self-expanded reaction (USER) in Ar atmosphere. This process not only immediately reduced GO but also significantly expanded films structure. The sample with the highest specific capacity and the highest stability consisted of GO and ex-MoS 2 with ratio of 1:1. The anode composed of this film showed approximately 6 times higher discharge capacity (916 mAh/g at 50 mA/g) than reference film (RGO/MoS 2 –1) where graphene oxide was thermally reduced in a furnace (145 mAh/g at 50 mA/g). Such high performance is associated with the expanded structure of ERGO allowing better lithiation yield and served as a protection of ex-MoS 2 against overexpanding upon charging/discharging process. What is more, the proposed Li-ion half-cells are free of any non-active materials e.g. carbon black or poly(vinyl difluoride) which are commonly used in batteries increasing the cost of the whole energy storage device. [Display omitted] [ABSTRACT FROM AUTHOR]

• Bifunctional composite photocatalyst based on mTiO 2 and ex-gCN was synthesized. • mTiO 2 _ex-gCN boosted two photocatalytic processes: RhB removal and H 2 evolution. • mTiO 2 _ex-gCN evolved 70 times higher amount of H 2 than pristine ex-gCN. • The improved photocatalytic property is due to synergic effect of both components. Here, we designed a molecular structure fabrication route based on spherical mesoporous TiO 2 and exfoliated graphitic carbon nitride (mTiO 2 _ex-gCN) by combining hard templating and hydrothermal methods. The mTiO 2 _ex-gCN boosted two photocatalytic processes: hydrogen evolution under simulated solar illumination and degradation of Rhodamine B (RhB) with the assistance of UV–vis and visible light irradiations. RhB degradation under UV–vis light was 2.94 and 1.39 times higher than ex-gCN and mTiO 2 , respectively. Additionally, dye degradation under visible light was enhanced by a 1.22 factor in respect to ex-gCN. However, a more spectacular performance was detected in the process of photocatalytic hydrogen evolution – the efficiency of the catalyst yielded a 70 times higher amount of H 2 in respect to ex-gCN. It is proposed that enhanced photocatalytic activity is due to synergy provided by individual counterparts, which tuned energy band gap, improved specific surface area, and enhanced ability to suppress the charge carrier recombination. [Display omitted] [ABSTRACT FROM AUTHOR]

In this contribution, the effect of hydrogenation conditions atmosphere (temperature and time) on physicochemical properties and photocatalytic efficiency of graphitic carbon nitride (g-C3N4, gCN) was studied in great details. The changes in the morphology, chemical structure, optical and electrochemical properties were carefully investigated. Interestingly, the as-modified samples exhibited boosted photocatalytic degradation of Rhodamine B (RhB) with the assistance of visible light irradiation. Among modified gCN, the sample annealed at 500 °C for 4 h (500-4) in H2 atmosphere exhibited the highest photocatalytic activity—1.76 times higher compared to pristine gCN. Additionally, this sample presented high stability and durability after four cycles. It was noticed that treating gCN with hydrogen at elevated temperatures caused the creation of nitrogen vacancies on gCN surfaces acting as highly active sites enhancing the specific surface area and improving the mobility of photogenerated charge carriers leading to accelerating the photocatalytic activity. Therefore, it is believed that detailed optimization of thermal treatment in a hydrogen atmosphere is a facile approach to boost the photoactivity of gCN. [ABSTRACT FROM AUTHOR]

Recently, to meet the growing demand for stable and flexible batteries, anodes in the form of thin films have drawn the attention of researchers. It is clear that mass production of such batteries would bring the worldwide distribution of flexible devices and wearable electronics closer. Currently, electrodes are deposited on a flexible substrate and consist of conductive and binding agents that increase the volume/weight of the electrode. Here, we propose free-standing and non-active-material-free thin films based on reduced graphene oxide (rGO), titanium dioxide (TiO2) and manganese dioxide (MnO2) as working electrodes in lithium-ion half-cells prepared via the vacuum-assisted filtration method. The electrochemical performance of the assembled half-cells exhibited good cyclic stability and a reversible capacity at lower current densities. The addition of TiO2 and MnO2 improved the capacity of the rGO film, while rGO itself provided a stable rate performance. rGO/TiO2/MnO2 film showed the highest discharge capacity (483 mAh/g at 50 mA/g). In addition, all assembled cells displayed excellent repeatability and reversibility in cyclic voltammetry measurements and good lithium-ion diffusion through the electrolyte, SEI layer and the active material itself. [ABSTRACT FROM AUTHOR]

This study presents a new approach towards the production of sol-gel silica-coated Bi2O3/Gd2O3 cement additives towards the improvement of early mechanical performance and radiation attenuation. Two types of silica coatings, which varied in synthesis method and morphology, were used to coat Bi2O3/Gd2O3 structures and evaluated as a cement filler in Portland cement pastes. Isothermal calorimetry studies and early strength evaluations confirmed that both proposed coating types can overcome retarded cement hydration process, attributed to Bi2O3 presence, resulting in improved one day compressive strength by 300% and 251% (depending on coating method) when compared to paste containing pristine Bi2O3 and Gd2O3 particles. Moreover, depending on the type of chosen coating type, various rheological performances of cement pastes can be achieved. Thanks to the proposed combination of materials, both gamma-rays and slow neutron attenuation in cement pastes can be simultaneously improved. The introduction of silica coating resulted in an increment of the gamma-ray and neutron shielding thanks to the increased probability of radiation interaction. Along with the positive early age effects of the synthesized structures, the 28 day mechanical performance of cement pastes was not suppressed, and was found to be comparable to that of the control specimen. As an outcome, silica-coated structures can be successfully used in radiation-shielding cement-based composites, e.g. with demanding early age performances. [ABSTRACT FROM AUTHOR]

Achieving the desired properties of paper such as strength, durability, and printability remains challenging. Paper mills employ calcium carbonate (CaCO3) as a filler to boost paper's brightness, opacity, and printability. However, weak interaction between cellulose fibers and CaCO3 particles creates different issues in the papermaking industry. Therefore, this study explores the influence of various inorganic additives as crosslinkers such as mesoporous SiO2 nanospheres, TiO2 nanoparticles, h-BN nanoflakes, and hydroxylated h-BN nanoflakes (h-BN-OH) on inorganic fillers content in the paper. They were introduced to the paper pulp in the form of a polyethylene glycol (PEG) suspension to enable bonding between the inorganic particles and the paper pulp. Our findings have been revealed based on detailed microscopic and structural analyses, e.g., transmission and scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and N2 adsorption/desorption isotherms. Finally, the inorganic fillers (CaCO3 and respective inorganic additives) content was evaluated following ISO 1762:2001 guidelines. Conducted evaluations allowed us to identify the most efficient crosslinker (SiO2 nanoparticles) in terms of inorganic filler retention. Paper sheets modified with SiO2 enhance the retention of the fillers by ~12.1%. Therefore, we believe these findings offer valuable insights for enhancing the papermaking process toward boosting the quality of the resulting paper. [ABSTRACT FROM AUTHOR]