Dye-sensitized solar cells properties from natural dye as light-reaping materials extracted from gayo arabica coffee husks

Abstract

The waste of coffee husks was extracted by maceration method using HCl in methanol. This process produced an extract of coffee husks of 1.176 mg/uL. The UV-Vis spectrum of the extract shows the major absorption peak at λmax=529 nm which is determined by the electronic transition from flavilium as a characteristic of anthocyanin compounds. Analysis of the IR spectrum shows that the O-H group at wave number 3328 cm-1, strain C-H at wave number 2925 cm-1, the C-C strain found in the aromatic ring at wave number 1422 cm-1 and the C-O group at wave number 1024 cm-1. Based on computational studies through the DFT/B3LYP/6-31G approach to the anthocyanin compound, the difference between HOMO and LUMO (energy gap) obtained for C3G and C3R is 3.37919316 eV and 0.28792381 eV, respectively. Therefore, the anthocyanin compounds in Gayo Arabica Coffee husks extract have potential as candidate photosensitizers in DSSC.