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High-temperature Li-ion batteries capable of operating up to 100 ℃ can replace lithium thionyl chloride primary batteries in specialized industrial applications. Room-temperature ionic liquids (RTIL) offer high thermal stability and can be a promising choice of electrolyte for high-temperature batteries. This work elucidates that high thermal stability alone does not guarantee effective battery operation due to the electrochemical instability observed in RTIL-LiTFSI mixtures at elevated temperatures. Here, we investigate the impact of varying electrochemical stability in RTILs on half-cell, full-cell, and calendar aging. Electrochemical instability of the electrolyte at the cathode interface injects additional electrons and Li-ions into the electrochemical cell, triggering a cascade of detrimental chain reactions that hinder efficient battery performance. We demonstrate that electrochemical information gathered from a full-cell configuration can frequently obscure the presence of electrochemical instability at the cathode surface. To accurately evaluate this instability, it is essential to perform in-depth half-cell studies and other characterizations. Our results indicate that cathode electrolyte interphase (CEI) can reach a thickness of up to 100 nm, with a depth-dependent composition showing higher concentration of inorganic species like LiF and LiNSO near the cathode surface. Further, accelerated calendar aging measurements of such cells at high temperature revealed complete irreversible self-discharge within as little as 14 days. These findings shed light on the critical factors influencing the stability and performance of cells under challenging operating conditions. [ABSTRACT FROM AUTHOR]

As the usage of antibiotics and vitamin tablets becomes more widespread, detrimental impacts on living beings are increasing by consuming polluted water contaminated with drug residues. Because of the emergence of drug-resistant bacteria, there is an increasing requirement for determining frequently accessible medicines in water sources. We have developed a rapid colorimetric sensor for the selective recognition of neomycin and thiamine. A simple reduction method was followed to synthesize citrate capped silver nanoparticles (AgNPs) as a sensor. The presence of functional groups and the surface charge of AgNPs were characterized by FT-IR and zeta potential measurements. The colloidal solution of AgNPs displayed an instantaneous chromatic change from yellow to purple and brown-red after the respective treatment with neomycin and thiamine, although the other drugs showed infectivity. The plasmonic characteristic peak at a 405 nm wavelength of AgNPs underwent a gradual decrease with an increase in the concentration of the drug. In addition, it showed a bathochromic shift and broadening to longer wavelengths of 520 nm and 565 nm after the incubation with neomycin and thiamine, respectively. The simultaneous quenching and shift of the plasmonic peak were ascribed to the aggregation of AgNPs in the presence of the analytes via hydrogen bonding and proved by spectroscopic and microscopic techniques. The colloidal AgNPs displayed an excellent performance for the determination of these drugs at concentrations ranging between 7.5 nM and 0.05 mM with low detection limits of 70.8 pM and 0.42 nM for neomycin and thiamine, respectively. The selectivity towards neomycin and thiamine was prolonged even in the presence of interfering drug mixtures and in real sample analysis. [ABSTRACT FROM AUTHOR]

Suppressing Li dendrite growth has gained research interest due to the high theoretical capacity of Li metal anodes. Traditional Celgard membranes which are currently used in Li metal batteries fall short in achieving uniform Li flux at the electrode/electrolyte interface due to their inherent irregular pore sizes. Here, the use of an ultrathin (≈1.2 nm) carbon nanomembrane (CNM) which contains sub‐nanometer sized pores as an interlayer to regulate the mass transport of Li‐ions is demonstrated. Symmetrical cell analysis reveals that the cell with CNM interlayer cycles over 2x longer than the control experiment without the formation of Li dendrites. Further investigation on the Li plating morphology on Cu foil reveals highly dense deposits of Li metal using a standard carbonate electrolyte. A smoothed‐particle hydrodynamics simulation of the mass transport at the anode–electrolyte interface elucidates the effect of the CNM in promoting the formation of highly dense Li deposits and inhibiting the formation of dendrites. A lithium metal battery fabricated using the LiFePO4 cathode exhibits a stable, flat voltage profile with low polarization for over 300 cycles indicating the effect of regulated mass transport. [ABSTRACT FROM AUTHOR]

Suppressing Li dendrite growth has gained research interest due to the high theoretical capacity of Li metal anodes. Traditional Celgard membranes which are currently used in Li metal batteries fall short in achieving uniform Li flux at the electrode/electrolyte interface due to their inherent irregular pore sizes. Here, the use of an ultrathin (≈1.2 nm) carbon nanomembrane (CNM) which contains sub‐nanometer sized pores as an interlayer to regulate the mass transport of Li‐ions is demonstrated. Symmetrical cell analysis reveals that the cell with CNM interlayer cycles over 2x longer than the control experiment without the formation of Li dendrites. Further investigation on the Li plating morphology on Cu foil reveals highly dense deposits of Li metal using a standard carbonate electrolyte. A smoothed‐particle hydrodynamics simulation of the mass transport at the anode–electrolyte interface elucidates the effect of the CNM in promoting the formation of highly dense Li deposits and inhibiting the formation of dendrites. A lithium metal battery fabricated using the LiFePO4 cathode exhibits a stable, flat voltage profile with low polarization for over 300 cycles indicating the effect of regulated mass transport. [ABSTRACT FROM AUTHOR]

In this work, multi-wall carbon nanotubes (MWCNTs with 1, 3 and 5 wt.%) are mixed with zinc oxide (ZnO) to prepare nanocomposites for energy conversion and storage applications. Further, UV–Vis spectra of synthesized pure ZnO and ZnO/MWCNTs nanocomposite material shows enhanced light absorption in the visible region. Hexagonal wurtzite crystal structure of the nanocomposites is confirmed by X-ray diffraction (XRD) spectra. Field emission scanning electron microscopy (FE-SEM) and High resolution-transmission electron microscopy (HR-TEM) images explores the formation of nanocomposite with flake like ZnO and tube structured MWCNTs at nanoscale region. Dye sensitized solar cells (DSSC) are constructed with pure and nanocomposite material as photoanode and the effect of addition of MWCNTs on the performance of solar cells are studied. Further, the cyclic voltammetry (CV), galvanic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) are employed to examine the electrochemical characteristics of the prepared electrode in a 1 M Na 2 SO 4 electrolyte. In three electrode configuration, the CV and GDC curves exhibits good reversibility and attains a specific capacitance value of 115.7 F g−1 with the addition of MWCNTs onto the ZnO. Also, the asymmetric supercapacitor device exhibits the improved storage performance. The EIS spectra shows lowest R s and R ct resistance, indicating the prepared electrode is favorable for DSSC and supercapacitor application. • 1, 3 and 5 wt.% MWCNTs mixed ZnO are prepared by sonication approach. • Optical and charge transfer behavior of MWCNTs mixed ZnO is better than pure ZnO. • The efficiency of DSSC is 4.37% when ZnO/3 wt.% MWCNTs used. • ZnO/3 wt.% MWCNTs electrode exhibits 115.72 F g−1 specific capacitance value. [ABSTRACT FROM AUTHOR]

• A bi-phasic titanium carbide MXene fabricated by thermal oxidation process. • TiO 2 -Ti 3 C 2 MXene material shows excellent light harvesting behaviour. • The MXene interfacial layer as improve the interfacial electron extraction. • The surface oxidized interfacial layer is achieved high 1.06 V oc and 1.31% PCE. In this study, thermal oxidation method is followed to prepare surface oxidized titanium carbide (TiO 2 -Ti 3 C 2) nanomaterial. Here, the formation of anatase phase TiO 2 nanoparticles over the surfaces of Ti 3 C 2 MXene is confirmed by UV–Vis, FT-IR, XRD and FE-SEM and HR-TEM studies. The TiO 2 -Ti 3 C 2 MXene acts an interfacial layer in double perovskite solar cell that exhibits high open circuit voltage (V oc of 1.01 V), short circuit current density (J sc of 2.64 mA/cm−2), fill factor (FF of 0.55) and power conversion efficiency (PCE of 1.35%) under ambient conditions. Hence, we suggest that this surface modified material will be useful for double perovskite photovoltaics applications. [ABSTRACT FROM AUTHOR]

Development of new polymeric binders can help enable the use of silicon-rich anodes in Li-ion batteries, by providing stronger adhesion to the active material particles. The compositional features that improve interfacial interactions and mechanical properties can often impart electronic conductivity and redox activity to these polymers, which are generally seen as beneficial to cell performance. Alternatively, it is also possible that the addition of charge-transferring centers to the electrode can accelerate cell degradation. Here, we use an aromatic polyimide (∼320 mA h/g of reversible capacity) to explore how a redox-active conductive polymer can affect cell performance. We demonstrate that the lithiated polymer is less stable than the traditional binders upon storage, leading to increased rates of calendar aging. Furthermore, we determine that the adhesion properties of the polymer deteriorate upon repeated cycling, to an extent that is proportional to the degree of delithiation of the binder. More critically, we establish that progressive degradation of the redox behavior of the polymer leads to the release of "extra" Li+ into the cell, which can give the false perception of good performance even under conditions of poor stability. Our work suggests that redox-active conductive binders can sometimes be detrimental to cell performance, and that works evaluating new polymers must include careful experimental validation under realistic conditions. • Aromatic polyimide has a reversible capacity of 320 mA h/g. • Reversible Li + storage occurs at aromatic rings. • Cells with a redox-active binder present faster calendar aging than with PVDF. • Polymer degradation "prelithiates" the cell and misleadingly improves performance. • Deleterious binder reactivity can occur even in seemingly high-performing cells. [ABSTRACT FROM AUTHOR]

Increasing attention has been focused in the area of multi-mode sensing method for on-site application to avoid the false positive results and enhance the accuracy label measurements. This article reports the synthesis of bright red fluorescent amphiphilic carbon dots (C-dots) as dualphase fluorescent nanosensor for selective detection of As3+ in water. One-pot solvothermal approach was chosen for the C-dots synthesis with a maximum fluorescence quantum yield of 47%. Bright red fluorescence of the C-dots was selectively weakened upon the treatment with As3+, although the other competing ions showed infectivity. Static quenching was proved behind this fluorescence attenuation by absorbance and time-resolved fluorescence spectroscopy. The amphiphilicity of synthesized C-dots has been utilized to detect As3+ in both liquid and solid phase. Aqueous dispersion of C-dots showed a dramatic fluorescence quenching efficiency of maximum 80%. To fabricate solid phase sensor, C-dots were successfully coated and absorbed on silica beads and cotton buds. These fluorescent solid matrices also displayed a relative good quenching efficiency (70–80%) towards As3+ without any leaching out of the C-dots from the solid surface. In addition, these C-dots showed an adequate potentiality to detect this ion in real water sample analysis. These findings would enable a great potentiality in the environmental water contaminants sensing technology. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Simplified colloidal synthetic approach of 2D Bi 2 WO 6 /g-C 3 N 5 heterostructure. • Effective remediation in wastewater containing colorless pharmaceutical antibiotics and pesticides. • Visible light induced detoxification of these environmental pollutants at the nanomaterials surface via Z-scheme pathway. • Excellent recycling capability of the photocatalyst. Colorless endocrine disruptors (EDs) are generally known as interference chemicals with the hormonal system. Widespread usage of such pollutants in daily life leads to the hike in the level of EDs in water resources as well as drinking water resulting in various health issues upon ingestion unknowingly. Thus, it is a challenging issue to efficiently degrade colorless EDs under visible light in spite the report of several photocatalysts. Herein, we fabricated a composite comprising metal-free graphitic carbon nitride (g-C 3 N 5) with Bi 2 WO 6 that exhibits visible light-induced efficient degradation of colorless EDs. A simple hydrothermal polymerization method was adopted to prepare nanosheets of g-C 3 N 5 loaded with Bi 2 WO 6 nanoplates and the resulting heterostructure efficiently degrade tetracycline, 2-mercaptobenzothiazole, and chlorpyrifos under cheap visible light irradiation in a short period of time. The synergistic effect of g-C 3 N 5 and Bi 2 WO 6 components in the composite leads to efficient separation of photogenerated charge carriers via Z-scheme pathway and resulting in remarkable photocatalytic activity compared to individuals. [ABSTRACT FROM AUTHOR]

The sub-nanometer porous membrane regulates the lithium-ion transport, creating a uniform lithium flux that prevents dendrite nucleation. Keywords: carbon nanomembranes; dendrite suppression; lithium metal batteries; separators; sub-nanometer porous membrane EN carbon nanomembranes dendrite suppression lithium metal batteries separators sub-nanometer porous membrane 1 1 1 08/07/21 20210805 NES 210805 B Lithium Metal Batteries b In article number 2100666, Andrey Turchanin, Leela Arava and co-workers incorporate a nanometer thick two-dimensional carbon nanomembrane onto a commercial polyolefin separator to inhibit the propagation of lithium dendrites in lithium metal batteries. Inhibition of Lithium Dendrite Formation in Lithium Metal Batteries via Regulated Cation Transport through Ultrathin Sub-Nanometer Porous Carbon Nanomembranes (Adv. [Extracted from the article]

The sub-nanometer porous membrane regulates the lithium-ion transport, creating a uniform lithium flux that prevents dendrite nucleation. Keywords: carbon nanomembranes; dendrite suppression; lithium metal batteries; separators; sub-nanometer porous membrane EN carbon nanomembranes dendrite suppression lithium metal batteries separators sub-nanometer porous membrane 1 1 1 05/24/22 20210801 NES 210801 B Lithium Metal Batteries b In article number 2100666, Andrey Turchanin, Leela Arava and co-workers incorporate a nanometer thick two-dimensional carbon nanomembrane onto a commercial polyolefin separator to inhibit the propagation of lithium dendrites in lithium metal batteries. Inhibition of Lithium Dendrite Formation in Lithium Metal Batteries via Regulated Cation Transport through Ultrathin Sub-Nanometer Porous Carbon Nanomembranes (Adv. [Extracted from the article]

• Barium-zirconium-cerate electrolytes are unstable in reactive steam conditions and require high sintering temperature. • We introduce tri-doping strategy for barium-zirconium-cerate mixture with rare earth elements Pr, Gd and Y as dopants. • This strategy mitigates sinterability issues while improving the chemical stability and proton conductivity. • The BaCe 0.5 Zr 0.2 Y 0.1 Gd 0.1 Pr 0.1 O 3-δ electrolyte shows a high relative density (98%) and large grain size (20 mm). • XRD and Raman analysis demonstrated the chemical stability for over 200 hours at 600 ˚C. • The ionic conductivity was, 3.11, 7.69 and 15.09 mS cm-1 in wet argon at 400, 500 and 600 ˚C, respectively. • The ionic conductivity of the electrolytes was stable over 240 hours in 50% wet argon atmosphere at 600 ˚C. • High chemical stability, proton conductivity and low sintering temperature to prepare highly dense electrolytes. [Display omitted] Tri-doping of barium cerium zirconate with rare earth elements praseodymium (Pr), gadolinium (Gd), and yttrium (Y) as dopants was followed to mitigate sinterability issues while improving the chemical stability and proton conductivity. The effect of the concentration of dopants was focused by varying the concentration of Pr and Y, and keeping the concentration of Gd, Zr and Ce constant in the 'B' site of perovskite structure (BaCe 0.5 Zr 0.2 Y 0.1 Gd 0.1 Pr 0.1 O 3-δ and BaCe 0.5 Zr 0.2 Y 0.15 Gd 0.1 Pr 0.05 O 3-δ). The sintering behavior, morphology, and grain boundary growth of the proton conducting electrolyte materials were systematically studied. The BaCe 0.5 Zr 0.2 Y 0.1 Gd 0.1 Pr 0.1 O 3-δ electrolyte shows high relative density and large grain size (20 µm) after sintering at a relatively low temperature (1350 °C). X-ray diffraction (XRD) and Raman spectroscopic analysis demonstrated the excellent chemical stability of the Pr-doped proton-conducting electrolyte in a moisture-rich argon atmosphere for over 200 h at 600 °C. The conductivity measurements revealed that the tri-doped electrolyte materials have high conductivity values, 3.11, and 15.09 mS cm-1 in wet Argon at 400, and 600 °C, respectively. The obtained values of conductivity of the electrolytes were found to be stable over 240 h in 50% wet argon atmosphere at 600 °C demonstrating the higher chemical stability of the electrolyte. [ABSTRACT FROM AUTHOR]

Carbon dots (C-dots) are emergent nanomaterials of carbon-based materials family and have gained significant research interest because of their environmental friendliness, brightness, tunable fluorescence, chemical inertness, low cost, simple synthetic route and availability for wide variety of starting materials. These are considered as potential competitor to conventional semiconductor quantum dots in terms of lower toxicity. It is found that their involvement in adverse fields of chemical and bio-sensing, bio-imaging, drug delivery, photocatalysis, electrocatalysis and light-emitting devices makes as an ideal and potential candidate. Interestingly they are treated as important and versatile platform for engineering multifunctional nanosensors. This review focuses on the remarkable research progress of high quality tunable fluorescent C-dots synthesis via familiar top-down and bottom-up approaches. Their fluorescence origin has been nicely demonstrated by quantum confinement effect, surface state and molecular fluorescence properties. Finally, selective and sensitive atmospheric prevailed volatile organic compounds recognition has been explained with C-dots in both solution and solid phase along with discussion on challenging and future research direction. [ABSTRACT FROM AUTHOR]

Aerosol formation in dental practice is almost inevitable and the potential risk of acquiring an infection due to airborne pathogens is very high. Dental procedures involving use of ultrasonics, air polishing, use of airotors and micromotors, air-water syringes and lasers emit large amount of aerosol and microbial pathogens from saliva, dental unit waterlines and respiratory tract. Depending on the nature of the bacteria/virus/fungi in the aerosol and its pathogenic nature, the microbe travels through the lung alveoli and affects the upper/lower respiratory system. The recent episode of COVID has driven further fear among dental professionals, as the virus sheds into air and transmits the disease. As dental professionals, it is essential that we take steps to prevent transmission by following universal precautions and social precautionary measures. This review revisits on the physics of aerosol formation, spatial microbiome in aerosol, the types of pathogens associated with dental procedures, risk of disease getting transmitted to dental healthcare workers and infection control. [ABSTRACT FROM AUTHOR]

COVID-19, an epidemic viral disease which originated in Wuhan, China, has caused a major halt in the normal routine of people worldwide. It was declared as a public health emergency of international concern by the World Health Organisation. The novel corona virus has caused major challenges to the health professionals owing to its different speed of reaction and types of response around the world. Due to the characteristics of dental setting and treatment modalities, the dental professionals and the patients are at major risk of cross infection. Periodontists can be at high risk while performing aerosol generating procedures to asymptomatic patients, as saliva has been identified in saliva of infected patients. This review article aims to discuss the effect of COVID-19 on periodontal practise and future changes to be done in the COVID-19 era. [ABSTRACT FROM AUTHOR]

Gingival enlargement or gingival overgrowth can be defined as increase in the size of gingiva, caused due to a variety of etiological factors. One of the causes of gingival enlargement is hereditary gingival fibromatosis, which is a genetic disorder characterised by progressive enlargement of the free and attached gingiva. It may have a nodular enlargement, having stippled surfaces with no inflammation or may show inflamed surface. Clinically, gingiva may present dense or firm surface on palpation. It is commonly associated with mutation of Son of Sevenless-1 (SOS-1) gene, which is responsible for this disease. This case report focuses on a family, diagnosed with hereditary gingival fibromatosis in three consecutive generations. This report also discusses the diagnosis, treatment, histopathological features and the pattern of inheritance associated, which is emphasised through pedigree analysis. [ABSTRACT FROM AUTHOR]

A sensitive electrochemical method for riboflavin (RF) detection based on Ce–NiO nanostructures was developed using a hydrothermal assisted chemical route. The created several oxygen vacancies on Ce doping are considered as the key factor for the magnificent electrocatalytic behavior of the Ce–NiO sample. The same oxygen vacancies also play an important role in antibacterial applications. Hence dual behavior of this Ce–NiO sample was investigated: (i) RF sensing was characterized by XRD, SEM, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV) using [Fe(CN)6]3−/4− and phosphate buffer solution (PBS) for probing the binding interaction between the Ce–NiO and RF. The Ce ions doped into the NiO nanostructure exhibit an excellent performance towards the detection of RF over a wide linear range from 1 mM to 50 nM, with a detection limit of 0.676 nM (3σ/b). (ii) Investigation of antibacterial activity using both Gram negative and positive bacterial strains. The minimal inhibitory concentration and minimal bactericidal concentration against B. Subtilis is found to be 10 μg ml−1. The diameter of the zone of inhibition for B. subtilis and S. aureus is quantified to be 22 and 18 mm respectively. Our results confirmed that Ce-doped NiO nanomaterial is a useful platform for electrocatalytic and biomedical applications. [ABSTRACT FROM AUTHOR]

Background and Aims: To assess the factors influencing the awareness and practice of oral hygiene among the local population Maduravoyal, Chennai, India. Materials and Methods: A cross-sectional questionnaire based study was conducted to understand the factors influencing the choice and practice of oral hygiene products among the population of Maduravoyal, Chennai, India. Data was collected by means of a self administered structured questionnaire written in English and validated through a pilot survey. One thousand two hundred and nine subjects, with an age range of 15 to 70 years, who visited the Department of Periodontology, Meenakshi Ammal Dental College, Chennai were selected for investigation. The data obtained was analyzed using the SPSS version 13.0. The frequency of distribution and percentages were calculated. Results: The results of the study showed that tooth brush (98.5%) and toothpaste (98%) were the main products used for the maintenance of oral hygiene and around 84.6% of the population brushed once daily. Information from the media (59.4%) and decay prevention (49.7%) were the major factors that influenced the choice of toothpaste among the study population. Conclusion: The major factor which influenced the choice of oral hygiene products was based on information obtained from advertisements and other sources. There is a need for the dental professionals to be aware of the ever-increasing development and marketing of oral hygiene products from various databases. Hence, the education of people regarding the importance of oral hygiene maintenance, proper selection of oral hygiene products is essential. [ABSTRACT FROM AUTHOR]

The lithium-sulfur (Li-S) redox battery system is considered to be the most promising next-generation energy storage technology due to its high theoretical specific capacity (1673 mAh g−1), high energy density (2600 Wh kg−1), low cost, and the environmentally friendly nature of sulfur. Though this system is deemed to be the next-generation energy storage device for portable electronics and electric vehicles, its poor cycle life, low coulombic efficiency and low rate capability limit it from practical applications. These performance barriers were linked to several issues like polysulfide (LiPS) shuttle, inherent low conductivity of charge/discharge end products, and poor redox kinetics. Here, we review the recent developments made to alleviate these problems through an electrocatalysis approach, which is considered to be an effective strategy not only to trap the LiPS but also to accelerate their conversion reactions kinetics. Herein, the influence of different chemical interactions between the LiPS and the catalyst surfaces and their effect on the conversion of liquid LiPS to solid end products are reviewed. Finally, we also discussed the challenges and perspectives for designing cathode architectures to enable high sulfur loading along with the capability to rapidly convert the LiPS. [ABSTRACT FROM AUTHOR]