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Introduction: With increasing prevalence of dental erosion, this study explores the protective role of traditional fluoride-based products and newer formulations on eroded enamel. Aims: To assess the protective effectiveness of casein phosphopeptide-amorphous calcium phosphate fluoride (CPP-ACPF) and sodium fluoride (NaF) on human enamel against erosion using surface microhardness (SMH) and Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses. Materials and Methods: Ten extracted human third molars were sectioned to obtain 40 enamel sections and randomly assigned into four groups (n = 10) and treated as follows: G1 (Sound Enamel), G2 (Erosive Challenge), G3 (CPP-ACPF + Erosive Challenge), and G4 (NaF + Erosive Challenge). All samples were subjected to Vicker's SMH analysis, while changes in surface morphology and elemental composition were validated in few representative samples using FTIR and SEM, respectively. Statistical Analysis: Paired samples test, Kruskal-Wallis test, and Tukey HSD test were performed using SPSS software version 23 setting P value < 0.05 as statistically significant. Results: The mean SMH1 values for the experimental groups G3 and G4 were significantly higher (426.58VHN and 455.83VHN) when compared to G1 (P = 0.000) and G2 (P = 0.000). In SEM analysis, G2 showed eroded honeycomb appearance compared to the smooth homogenous surface of G1, while both G3 and G4 showed deposition of some precipitates. FTIR analysis revealed that in G3 and G4, a characteristic peak of phosphate vibrations between 528 and 823 cm-1 and carbonate bands at 845-932 cm-1 was observed. Conclusions: Both CPP-ACPF and NaF demonstrated a protective effect on enamel against erosive challenge by an orange juice-based beverage. [ABSTRACT FROM AUTHOR]

Here, we synthesized metal-free organic dye (CCPICPB) with two carbazole donor groups and two anchoring groups that exhibit a panchromatic absorption in the near-infrared range of up to 750 nm. To study the photophysical properties of synthesized CCPICPB dye, the UV–Vis and cyclic voltammetric experiments were studied and the obtained results were validated with theoretical simulation studies. After that, the solvothermal approach is used to synthesize pristine anatase and calcium (Ca)-doped TiO2 microspheres with a smooth morphology. These microstructures are examined in depth using XRD, electron microscopy and electrochemical analysis methods. On TiO2 and Ca-doped TiO2 photoanode materials, we first evaluated the performance of CCPICPB dye. Upon our optimized experimental condition, the 3% Ca-TiO2 photoanode-based device exhibits an efficiency of 4.04%, which is greater than that of the pristine TiO2 photoanode-based device (2.93%). Because of the quicker electron transport in the Ca-TiO2 film, the short-circuit current density and efficiency of DSSCs were improved. Moreover, when the CCPICPB dye was used as a co-sensitizer with the common Ru(II) dye (Z907), interestingly it showed the highest efficiency (6.11%) when compared with Z907 alone (5.12%). This improved efficiency of the co-sensitized device resulted from greater VOC conjugated with improved JSC. The JSC was improved because CCPICB dye could compensate for the photocurrent loss caused by redox electrolyte while the VOC was improved because electron recombination was inhibited under the co-sensitization conditions. [ABSTRACT FROM AUTHOR]

We synthesized POBA dye and studied its performance as a sensitizer and co-sensitizer. In addition, we present a simple method for producing Ni-doped TiO2 with various molar concentrations for use as a photoanode in a DSSC. Further, poly(vinylidene fluoride)/polyethylene glycol (PVDF-PEG) gel polymer electrolytes (GPEs) having different concentrations of 1-n-hexyl-3-methylimidazolium iodide were prepared and optimized for usage in DSSCs. We initially tested the performance of POBA dye on TiO2 and Ni-doped TiO2 photoanode materials. Among the POBA sensitized devices, 4% Ni–TiO2 showed a high efficiency of 1.85%. Then, we sensitized Z907 dye on the 4% Ni–TiO2 photoanode, followed by sensitizing it with POBA, which compensated the absorption defect of the Z907 dye as well as filling the gap between the standard dye molecules. This approach enhances and broadens the absorption spectrum of the dyes by molecular filling, compensates for the lack of absorption of Z907, and reduces the recombination of charges. The Z907-based DSSC showed 4.52% efficiency, and after co-sensitization, the DSSC showed an increase in efficiency (5.77%). These findings show that co-sensitizers can cover the naked spectrum in the ultraviolet-visible region, fill the empty space on Ni–TiO2, and reduce recombination reactions. The main motive of this research is to enhance the photo-ability of sensitizers and metal-free co-sensitizers in a Ni–TiO2 photoanode and blend gel polymer electrolyte-based DSSCs. [ABSTRACT FROM AUTHOR]

Summary: To investigate the photovoltaic capabilities as a sensitizer and co‐sensitizer for dye‐sensitized solar cells (DSSCs), a new metal‐free organic dye (CDIB) was synthesized. In addition, different concentrations of 1‐n‐hexyl‐3‐methylimidazolium iodide ionic liquid (IL) doped poly(vinylidene fluoride‐hexafluoropropylene) gel polymer electrolytes are prepared and the high conductive electrolyte is used to fabricate the devices. The device having CDIB sensitizer and IL‐15% electrolyte showed an efficiency of 1.86%. Further, the effect of CDIB co‐sensitization on Z907 is examined. Consequently, the power conversion efficiency of DSSC with co‐sensitized dye is raised by 23.29%, from 4.55 to 5.61%, when compared to DSSCs with individual dyes. This improvement is mostly due to an increase in a short‐circuit current density and open‐circuit voltage. Highlights: Co‐sensitization is being used to enhance the performance of DSSCs.Poly(vinylidene fluoride‐hexafluoropropylene)‐based gel polymer electrolytes doped with different amounts of 1‐n‐hexyl‐3‐methylimidazolium iodide were prepared for improving the conductivity of electrolyte.A co‐sensitized DSSC has an efficiency of 5.61%.With co‐sensitization, both VOC and JSC increased significantly. [ABSTRACT FROM AUTHOR]

Summary: In the present context of increasing population, renewable and sustainable energy alternatives are very much essential to satisfy the necessities of the world. To satisfy this growing demand, scientists are prioritizing the production of cost‐effective and high‐performance clean energy appliances. Dye‐sensitized solar cells (DSSCs) are one such material that is at the forefront of modern solar cell technologies. Being one of the main components of DSSCs, metal‐free organic dyes play a crucial role in light processing and electron injection. In recent times, carbazole (CZ)‐, triphenylamine (TPA)‐, and phenothiazine (PTZ)‐based derivatives have been identified as suitable alternatives to Ru(II) polypyridyl complexes because they are easy to synthesize and exhibit excellent thermal and electronic properties. This review focuses largely on the latest developments in the use of monoanchored and multianchored CZ, TPA, and PTZ scaffolds for DSSC applications and focuses especially on the correlation between molecular design and photovoltaic performance. The physical properties of devices can be adjusted through the sensitizer's strategic design that helps to improve the performance of the devices. We tabulated the photovoltaic parameters corresponding to all dyes presented in this review. Also, applications of additives are presented after the systematic review on CZ‐, TPA‐, and PTZ‐based dyes. [ABSTRACT FROM AUTHOR]

ZnO/rGO composites are prepared by the conventional solid-state reaction method. Structural properties of prepared compounds were studied using XRD technique and it is observed that all the samples are crystallized in wurtzite structure. Electrical resistivity measurements were carried out using four probe method employing a closed cycle refrigerator. With addition of rGO, colossal reduction in the resistivity is observed which is about three orders of magnitude smaller than that of the pure sample of ZnO. Room temperature Hall measurements were performed to estimate the bulk concentration and results show that addition of rGO into ZnO matrix enhances the number of charge carriers. Thermopower measurements were carried out using differential dc method and a large reduction in Seebeck coefficient is observed. [ABSTRACT FROM AUTHOR]

Due to the outstanding high power conversion efficiency and mechanical robustness, photovoltaic systems have become a perfect alternative to traditional sources of energy. This helps in fulfilling the human demand for renewable, inexpensive and compact electricity sources. The production of highly efficient flexible dye-sensitized solar cells (FDSSCs) has sparked a lot of attention in recent years. These FDSSCs are promising energy sources for battery-free and self-powered electronics, which have application in different sectors, including the Internet of Things. Due to the intermittent and unpredictable nature of solar radiation, photoelectric conversion devices fail to satisfy the criteria of constant power output. Owing to the emergence of rechargeable electric energy storage devices, the integration of FDSSCs and rechargeable electric energy storage systems has become a promising approach in solving this problem. This review focused on the recent developments in terms of the materials used to fabricate FDSSCs along with the working principle, challenges in FDSSCs and improvements made in photoanode, sensitizer, electrolytes and counter electrode materials. In addition, some of the general characterization methods for newly prepared flexible/rigid dye-sensitized solar cell materials and the device are summarized. The evolution of many forms of mainstream flexible integrated photorechargeable energy storage systems, prospects for the development of highly effective, reliable FDSSCs and their integrated devices have also been demonstrated. [Display omitted] • Recent advancements in flexible dye-sensitized solar cell materials are discussed. • Characterization methods for different components and produced devices are explored. • The developments of integrated flexible dye-sensitized solar cells are addressed. • The key outcomes and importance of each material used were highlighted. • Describes promising methods for improving and stabilizing the device efficiency. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are an efficient and versatile method of transforming the clean and most plentiful energy resources available. DSSC is translucent to some extent and relatively inexpensive than the traditional solar cell. Thus, it may be a possible source of electricity for the future. But other things need to be focused on before it is considered a viable commercial product. The review discusses these facets and the numerous changes the DSSC has experienced in the recent years. Photoelectric conversion systems struggle to fulfil the specifications of constant power output owing to the erratic and unstable characteristics of the solar radiation. With the evolution of rechargeable electric energy storage systems (ESSs), the integration of a DSSC and ESSs has developed into a promising approach to solve this issue. Here, we describe the working principle, recent progress of DSSCs, including photoanodes, sensitizers, electrolytes, and counter electrodes, and the use of DSSCs in energy storage, targeting DSSC and supercapacitor (SC) integrated devices. The future prospects for highly effective, reliable DSSC and DSSC-SC development have also been highlighted. [Display omitted] • Recent progress in dye sensitized solar cell materials are reviewed. • Developments of photo-supercapacitors are reviewed. • Highlighted main outcomes and significance of each material used. • Describes promising ways to stabilize and improvise the performance of the device. [ABSTRACT FROM AUTHOR]

The development of antimicrobial coatings in various sectors is escalating nowadays. However, design, synthesis, and fabrication of simple antimicrobial polymer coatings with potent biocidal action against pathogenic microbes are necessary to emerge. The current article deals with fabrication of high efficient ultrathin coatings of synthesized polymer for controlling pathogenic bacteria and fungi. The article is intensified with simple synthesis, characterization, fabrication of ultrathin coatings and their antimicrobial studies. The polymer structure is elucidated by FTIR,1HNMR, and 13CNMR, and the thermal properties are explained by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The antimicrobial activity of a polymer and their ultrathin coatings against Escherichia coli, Staphylococcus aureus, tubercular‐variant Mycobacterium smegmatis, and Candida albicans are reported elaborately. The morphology of ultrathin coating and their interaction with microorganisms are studied using a scanning electron microscope and an atomic force microscope. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47893. [ABSTRACT FROM AUTHOR]