No abstract

Adsorption of dibenzothiophene (DBT) from model oil was investigated using composites of pure activated charcoal and pure bentonite clay. DBT adsorption was carried out in batch mode experiments at laboratory scale, where the developed composite materials showed a synergistic effect in removal of DBT from the model oil in terms of improved surface acidity of the pure activated charcoal and mesoporous structure of the pure bentonite clay. Thermodynamics, kinetics, and optimization of various adsorption parameters were investigated. Kinetic analyses proved that DBT adsorption followed pseudo‐second‐order kinetics. To study the thermodynamics of the adsorption, different isotherm adsorption models were applied. The Langmuir isotherm best fitted to the adsorption data. Various thermodynamic parameters were evaluated, including Gibbs free energy, entropy, and enthalpy.

The effect of sodium carbonate (Na 2 CO 3 ) treatment of short bamboo fibres on mechanical properties and water absorption character of polyester composite is investigated. Treatment time and Na 2 CO 3 concentration were optimised to 6 h and 5 wt-% respectively. Microscopy of the treated fibres showed a significant change in surface texture whereas; FTIR suggested the removal of amorphous compounds from the fibres that resulted in enhanced interfacial bonding between fibres and the polyester matrix. Removal of amorphous compounds was also confirmed by TGA where material loss for untreated fibres was 15% higher than the treated fibres. Composites were prepared using 10, 20 and 30 wt-% of treated and untreated fibres. Good interfacial bonding, achieved by the fibre treatment, enhanced the strength (∼24 MPa),( decreased the impact energy (from ∼36×10 −3 KJ/m 2 to ∼33×10 −3 KJ/ m 2 ) and improved the water absorption resistance (∼2%) in case of 20 wt-% fibres composite.

C u 2 NiSn S 4 is a non-toxic earth abundant material and a promising quaternary semiconductor compound. Due to its optimum direct band gap, it has been considered as a suitable absorber material for photovoltaic cells. It is a conspicuous and suitable class of material for the fabrication of low cost and high efficiency thin film devices. This paper presents numerical modeling for the efficiency enhancement of Cu2NiSnS4 based experimental photovoltaic cells. In this work, the experimental cell results were reproduced in the SCAPS software. These simulated results are validated and compared with the experimental reference cell. Cu2O as the hole transport layer is also proposed for further efficiency enhancement of the photovoltaic cell. After optimization of cell parameters, the power conversion efficiency of an optimized device is increased up to 4.60%. By applying the hole transport layer and analyzing the minority carrier life time, the conversion efficiency increases up to 10.35%. This work presents a novel concept in numerical modeling by analyzing the experimental solar cell, which will categorically offer new directions for the fabrication of high efficiency photovoltaic devices.

Solvothermal synthesis of Ni-Co-MOF/graphene nanoplatelets (GNPs) nanocomposites was done for their potential application as electrode material in energy storage devices. Addition of GNPs and metallic precursors together with 2-methylimedazole in the same autoclave reactor produced smooth-nanoflakes like Ni-Co-MOF/GNPs nanocomposites as evaluated by SEM. XRD analysis showed the presence of GNPs where GNPs do not affect the growth of MOF crystals and Ni-Co-MOF crystalline phases remain unaffected in the composite structure. FTIR analysis confirmed the presence of organic links forming nickel-cobalt metal cations framework. Electrochemical testing(CV,EIS,GCD) of the produced composites demonstrated that GNPs addition can enhance the charge storage performance of MOFs nanocomposites. The largest cycle area and most discharge time have been shown by Ni-Co-MOF/GNP-50 composite electrode that delivered the highest specific capacity values (313 Cg-1@1 Ag-1), good reversibility and low internal resistance and charge transfer resistance. Moreover, Ni-Co-MOF/GNP-50 composite exhibited good thermal stability with 28% weight loss during thermogravimetric analysis. The electrochemical evaluations performed on asymmetric supercapacitor real device expressed a specific capacity of 136.5 Cg-1@0.5 Ag-1, maximum energy density of 32.2 Whkg-1@425 Wkg-1 and maximum power density of 17000 Wkg-1@12.8 Whkg-1. Moreover, the device showed a stability performance of 92.5%@10 Ag-1 after 5000 CD cycles.