Recent advances in heterogeneous catalysis for green biodiesel production by transesterification

Investigation of CaO nanocatalyst synthesized from Acalypha indica leaves and its application in biodiesel production using waste cooking oil

The present study focused to synthesize the copper oxide nanoparticles (CuONPs) using novel Canthium coromandelicum leaves in a cost-effective, easy, and sustainable approach. The obtained Canthium coromandelicum-copper oxide nanoparticles (CC-CuONPs) were characterized using UV-Visible spectroscopy, FT-IR analysis, FESEM, HR-TEM imaging, and XRD study. The XRD pattern verified the development of crystalline CC-CuONPs with an average size of 33 nm. The biosynthesized CC-CuONPs were roughly spherical, according to HR-TEM and FESEM analyses. FT-IR research verified the existence of functional groups involved in CC-CuONPs production. Cu and O2 have high-energy signals of 78.32% and 12.78%, respectively, according to data from EDX. The photocatalytic evaluation showed that synthesized CC-CuONPs have the efficiency of degrading methylene blue (MB) and methyl orange (MO) by 91.32%, 89.35% respectively. The findings showed that biosynthesized CC-CuONPs might effectively remove contaminants in an environmentally acceptable manner. 

Enhanced photocatalytic activity of novel Canthium coromandelicum leaves based copper oxide nanoparticles for the degradation of textile dyes.

Nanotechnology emerged as a scientific innovation in the 21st century. Metallic nanoparticles (metal or metal oxide nanoparticles) have attained remarkable popularity due to their interesting biological, physical, chemical, magnetic, and optical properties. Metal-based nanoparticles can be prepared by utilizing different biological, physical, and chemical methods. The biological method is preferred as it provides a green, simple, facile, ecofriendly, rapid, and cost-effective route for the green synthesis of nanoparticles. Plants have complex phytochemical constituents such as carbohydrates, amino acids, phenolics, flavonoids, terpenoids, and proteins, which can behave as reducing and stabilizing agents. However, the mechanism of green synthesis by using plants is still highly debatable. In this report, we summarized basic principles or mechanisms of green synthesis especially for metal or metal oxide (i.e., ZnO, Au, Ag, and TiO2, Fe, Fe2O3, Cu, CuO, Co) nanoparticles. Finally, we explored the medical applications of plant-based nanoparticles in terms of antibacterial, antifungal, and anticancer activity.

Green Synthesis of Metal and Metal Oxide Nanoparticles Using Different Plants’ Parts for Antimicrobial Activity and Anticancer Activity: A Review Article

This review literature focuses on the current state of green synthesis of copper and copper oxide (Cu/CuO)-based nanomaterial utilizing plant extracts as reducing and capping agents, and the paper discusses the antimicrobial applications of these biomaterials. Additionally, a novel hypothetical mechanism for the antimicrobial activity of biosynthesized Cu/CuO nanomaterial was proposed. This study will shed light on the future of the green production of Cu/CuO nanomaterial in antimicrobials. This review discusses the synthesis approach and the plant parts that have been utilized previously, allowing researchers to gain a brief understanding of the synthesis procedure employing plant extracts. Moreover, this paper includes an overview of the various analytical approaches used to characterize the produced nanomaterials and a summary of the microbial strains used in this area that have been studied thus far. Finally, the paper discusses the difficulties and potential prospectives associated with the synthesis of Cu/CuO nanomaterials from plant extracts. • Green synthesis of Copper and Copper oxide (Cu/CuO)-based nanomaterials utilizing plant extracts is reviewed. • The optimization parameters in the green synthesis method using plant extracts are elaborated. • Different characterization techniques have been discussed. • A broad literature review of Cu/CuO-based nanomaterials in antimicrobial application. • The mechanism of antimicrobial property was discussed. 

Green synthesised copper and copper oxide based nanomaterials using plant extracts and their application in antimicrobial activity: Review

Terminalia chebula as a novel green source for the synthesis of copper oxide nanoparticles and as feedstock for biodiesel production and its application on diesel engine

One-step solution auto-combustion process for the rapid synthesis of crystalline phase iron oxide nanoparticles with improved magnetic and photocatalytic properties

Herein, we report the band structure engineering in titanium oxynitrides by annealing the titanium nitrides (TiN) in the ambient conditions at different temperatures. The parametric studies via increasing the annealing temperature from 450 to 650 °C (3 h) revealed the formation kinetics of oxynitride system. The TiNannealed at 450 and 550 °C showed the XRD peaks corresponding to titanium oxynitride, and mixed phases of anatase, rutile TiO2, whereasthe TiN annealed at 650 °C was found to be pure rutile phase of TiO2. Interestingly, the mixed phase-TiON(550 °C) showed the well-reduced band gap energy and visible light activity as compared to the other samples.

Band structuring engineering in titanium oxynitrides for the visible light driven photocatalytic applications

Among various oxyhalides-based layered nanomaterials investigated for the photocatalytic applications, bismuth oxyhalides (BiOX, X=Cl, Br, and I) have gained great curiosity due to their outstanding optical and electrical properties. With fascinating characteristics, such as tunable band gaps, better charge carrier transportation, nontoxicity, and high chemical stability, BiOX is considered as one of the most favorable candidates for the visible-light-driven photocatalytic applications. Accordingly, various strategies, such as synthesizing bismuth-rich BiOX photocatalysts, coupling among BIOX photocatalysts, metal and nonmetal doping, formation of heterojunctions and Z-scheme, defect engineering, and creating oxygen vacancies, have been explored to tune the band edge potentials, thereby to further enhance the photocatalytic performance of BiOX materials. In this context, this chapter provides insights into the structural properties of BiOX along with discussion on the mechanics of BiOX photocatalysts, their synthesis methods, and various design strategies for their effective photocatalytic applications.

Oxyhalides-based photocatalysts: the case of bismuth oxyhalides

This study demonstrates that the gasoline can be used as a co-solvent towards the modification of feedstock such as waste cooking oil for the synthesis of biodiesel via transesterification reaction, where the gasoline is removed from the reaction solution after the treatment. Parametric studies including varying the amount of co-solvent with respect to the feedstock, methanol/oil molar ratio, catalyst amount, reaction temperature, time, and stirring speed have been conducted to optimize the experiment. Our results show that biodiesel with a yield of ~ 99.4% is achieved at optimized conditions viz. 10% v/v co-solvent with respect to the feedstock, 0.6 wt% catalyst concentration, 6:1 molar-ratio, 50 °C temperature, 40 min reaction time, and 350 rpm stirring speed, while it is ~ 82.3% without the addition of co-solvent in the reaction solution under the same conditions. The thermodynamic parameters such as frequency factor, activation-energy, enthalpy, and entropy of the system have been estimated to be 1.3 × 104 min−1, 34.04 kJ mol−1, 31.48 kJ mol−1, and − 0.17 kJ mol−1 k−1, respectively. Further, various properties of the biodiesel produced with and without the feedstock modification have also been quantitatively measured and the developed approach favoured the feedstock modification towards improving the biodiesel yield and its physicochemical properties.

C. Ningaraju

Papers

Terminalia chebula as a novel green source for the synthesis of copper oxide nanoparticles and as feedstock for biodiesel production and its application on diesel engine

One-step solution auto-combustion process for the rapid synthesis of crystalline phase iron oxide nanoparticles with improved magnetic and photocatalytic properties

Band structuring engineering in titanium oxynitrides for the visible light driven photocatalytic applications

Oxyhalides-based photocatalysts: the case of bismuth oxyhalides

Gasoline pre-treated feedstock for the production of biodiesel with improved physicochemical properties