Redox Replacement of Silver on MOF-Derived Cu/C Nanoparticles on Gas Diffusion Electrodes for Electrocatalytic CO2 Reduction.

Bimetallic tandem catalysts have emerged as a promising strategy to locally increase the CO flux during electrochemical CO2 reduction, so as to maximize the rate of conversion to C-C-coupled products. Considering this, a novel Cu/C-Ag nanostructured catalyst has been prepared by a redox replacement process, in which the ratio of the two metals can be tuned by the replacement time. An optimum Cu/Ag composition with similarly sized particles showed the highest CO2 conversion to C2+ products compared to non-Ag-modified gas-diffusion electrodes. Gas chromatography and in-situ Raman measurements in a CO2 gas diffusion cell suggest the formation of top-bound linear adsorbed *CO followed by consumption of CO in the successive cascade steps, as evidenced by the increasingνC-H bands. These findings suggest that two mechanisms operate simultaneously towards the production of HCO2 H and C-C-coupled products on the Cu/Ag bimetallic surface.

A Metal-Organic Framework derived Cux Oy Cz Catalyst for Electrochemical CO2 Reduction and Impact of Local pH Change.

Developing highly efficient and selective electrocatalysts for the CO2 reduction reaction to produce value-added chemicals has been intensively pursued. We report a series of Cux Oy Cz nanostructured electrocatalysts derived from a Cu-based MOF as porous self-sacrificial template. Blending catalysts with polytetrafluoroethylene (PTFE) on gas diffusion electrodes (GDEs) suppressed the competitive hydrogen evolution reaction. 25 to 50 wt % teflonized GDEs exhibited a Faradaic efficiency of ≈54 % for C2+ products at -80 mA cm-2 . The local OH- ions activity of PTFE-modified GDEs was assessed by means of closely positioning a Pt-nanoelectrode. A substantial increase in the OH- /H2 O activity ratio due to the locally generated OH- ions at increasing current densities was determined irrespective of the PTFE amount.

Zn-ion Batteries: Charge Storing Mechanism and Development Challenges.

Improving the energy share of renewable energy technologies is the only solution to reduce greenhouse gas emissions and air pollution. The high-performing green battery energy storage technologies are critical for storing energy to address the intermittent nature of renewable energy resources. In recent years, aqueous batteries, particularly Zn-ion batteries (ZIBs), have achieved and shown great potential for stationary energy storage systems owing to their low cost and safer operation. However, the practical applications of the ZIBs have significantly been impeded due to the gap between the breakthroughs achieved in academic research and industrial developments. The present review discusses the ZIB's advantages, possibilities, and shortcomings for stationary energy storage systems. The Review begins with a brief introduction to the ZIBs and their charge storage mechanisms based on the structural properties of cathode materials. The scientific and technical challenges that obstruct the commercialization of the ZIBs are discussed in detail concerning their impact on accelerating the utilization of the ZIBs for real-life applications. The final section highlights the outlook on research in this flourishing field.

Rare case of gemination of mandibular third molar-A case report.

Fusion and germination are the anomalies that occur due to some developmental eccentricity during the time of morpho-differentiation of the tooth bud and have a close resemblance to each other. The gemination is an attempt of the division of a single tooth into two and, hence, appears as an enlarged single tooth while the tooth count is normal when the affected tooth is counted as one. Its exact pathogenesis is ambiguous. This anomaly has been observed mostly in deciduous dentition as compared to that in permanent dentition. Gemination is rarely associated with the third molar and, hence, the terminology is arguable when this condition is seen in relation to the third molar. In the present article, a case of germination of mandibular third molar has been reported.

Role of Nanotechnology in Dentistry: Systematic Review.

AIM: This systematic review aimed to provide an overview of role of nanotechnology in dentistry and to evaluate its applicability in prevention and treatment of oral diseases. MATERIALS AND METHODS: A systematic literature search was conducted in 2 electronic databases - PMC and Cochrane. The search was restricted to the articles published during the last 5 years. First-level screening was done to select articles for the review on the basis of title and abstract. Then, full texts of selected articles were studied, and relevant articles were selected to be included in this review. Articles selected were critically appraised to evaluate their quality. RESULTS: Literature search revealed 837 articles in PMC, 15 in Clinical trial register of US National library, and 43 in Cochrane. Additional 6 articles were identified by hand search. Eleven clinical trials were included in this review. CONCLUSION: Advancement in nanotechnology has greatly influenced dental disease prevention and therapy significantly.