This paper presents a novel design for the top contact of thin film photovoltaic (PV) solar cells. The new top contact is formed by fabricating a 20nm thin honeycomb shaped silver mesh on top of an ultra-thin 13nm of indium tin oxide. The new top contact offers the potential to reduce the series resistance of the cell while increasing the light current via plasmonic resonance. Using the nano-bead lithography technique the honeycomb top contact was fabricated and electrically characterized. Th...
Titanium dioxide (TiO2) nanostructures (nanorods and nanoparticles) were prepared using a low-cost microwave irradiation method from a polyol medium of glycerol. Titanium glycerolate and TiO2 powders were obtained in the glycerol medium for the first time with four different power densities (240 W, 480 W, 720 W, 960 W) of irradiation using a domestic microwave oven of 2.45 GHz, to understand the impact of power on morphology tuning. The structural and morphological features of the t...
A full mechanical characterisation of three types of 3-D printed lattice cores was performed to evaluate the feasibility of using additive manufacturing (AM) of lightweight polymer-based sandwich panels for structural applications. Effects of the shape of three selected lattice structures on the compression, shear and bending strength has been experimentally investigated. The specimens tested were manufactured with an open source fused filament fabrication-based 3-D printer. These sandwich st...
Anatase TiO2 displaying dual morphologies were synthesized with a simple chemical route via a single step. A strong correlation between the dye sensitized solar cell (DSSC) device performance and the obtained dual morphologies are highlighted using relevant evidences from UV-vis and diffuse reflectance spectroscopy (DRS), Raman analysis, field emission scanning electron microscope, high resolution transmission electron microscope, current-voltage characteristics and impedance analysis. Struct...
In this work, upgraded metallurgical grade silicon (UMG-Si) wafer was used to fabricate mesoporous nanostructures, as an effective antireflection layer for solar photovoltaic cells. The length of the vertical Si nanostructure (SiNS) arrays was altered by varying the etching time period during metal assisted chemical etching (MACE) process, using a silver catalyst. The optical, structural, morphological changes and the antireflection properties of Si nanostructures formed on UMG-Siwafer were a...
Fab labs, which offer small-scale distributed digital fabrication, are forming a Green Fab Lab Network, which embraces concepts of an open source symbiotic economy and circular economy patterns. With the use of industrial 3D printers capable of fused particle fabrication/ fused granular fabrication (FPF/FGF) printing directly from waste plastic streams, green fab labs could act as defacto recycling centers for converting waste plastics into valuable products for their communities. Clear finan...
Etrudate characteristics of briquettes produced and effects of extrusion factors using an existing screw extruder have been investigated. The feedstock material used in the test is sawdust collected from sawmills around Ibadan metropolis. Particle distribution analysis of materials collected showed that the size varies between 6-8 mm with 10-20% powdery component (< 4 mesh) which is known to give better products. Samples of briquettes produced were used for physical characterization. Physical...
This paper presents a systematic approach to develop a wear model of Al-Cu-Mg/Palmkernel shell ash particulate composites (PKSAp) produced by double stir -castingmethod. Four factors, five levels, central composite, rotatable design matrix was usedto optimize the number of experiments. The factors considered were sliding velocity,sliding distance, normal load and mass fraction of PKSA reinforcement in the matrix.Response surface methodology (RSM) was employed to develop the mathematicalmodel....