Low-cost visible spectrophotometer for detecting absorption and emission in metallic blends of colorful samples solution

Abstract

The innovative, affordable assembled visible spectrophotometer employed in this study aims to analyze the absorption and emission of colorful metallic blends of colorful samples solution. It features a tungsten white light bulb source, an ammeter as a detection element, a digital voltmeter, a diffraction grating for light dispersion, a converging lens for light collimation, and filters of various wavelengths (blue, red, yellow, and yellow-green). The light bulb source was powered by a standard supply set at 6 V. Using metallic solutions of chromium chloride (CrCl₃) and copper sulphate (CuSO₄) with different filter wavelengths, the performance was assessed. The transmittance and absorbance of these metallic solution samples exhibit a linear relationship with approximately 3 % deviation compared to results from a commercial UV–VIS spectrophotometer (DR-6000). Similar investigations were conducted with equivalent quantities of CuSO₄, CrCl₃, and nickel chloride (NiCl₂) solutions, showing a discrepancy ranging from 2 % to 8 % when compared with the commercial UV–VIS spectrophotometer. Therefore, in low-income countries like Ethiopia, colorful metallic solution samples can be effectively analyzed using the newly designed low-cost spectrophotometer.