Research On Pigment-protein Complexes Extracted From Photosynthetic Bacteria And Biological Solar Cell

The solar cells based on the principle of photosynthesis organisms have greatpotential for development because they are low-cost and environmentally friendly. In thispaper, a photosynthetic bacterium-Rhodopseudomonas was used as research subjects.The cultivation of bacteria, the extraction of pigment-protein complexes, TiO2solar cellssensitized by extracted proteins, as well as photosynthetic bacteria solar cell were studied.Photosynthetic bacteria was inoculated with the liquid and solid SMN medium.Bacterial growth conditions were discussed. Biological forms of photosynthetic bacteria(PSB) under an optical microscope and transmission electron microscope were studied.The results showed that the color of photosynthetic bacteria turned red after Gram stained,the shape was rod and arc.Pigment-protein complexes were extracted from PSB by ultrasonic crushing andrepeated freezing and thawing method. The results showed that the extractedpigment-protein complexes had absorption peaks at375nm,501nm,520nm,595nm,802nm and880nm. The extracted protein was sensitized TiO2solar cells. The resultsshowed that the open circuit voltage, short circuit current and the internal resistance ofbattery were279mV,10mA and27.9, respectively.Assembly and the battery performance of the new photosynthetic bacteria solar cellwere studied. The cell performances were investigated with the different additives additionto the anolyte, and the performance impact of different anode materials for photosyntheticbacteria solar cell was also studied. The results showed that the photosynthetic bacteriasolar cell could produce13μA polarization current under illumination. Glucose andchitosan as additives could promote photosynthesis of photosynthetic bacteria, so that thepolarization current under illumination increased to21μA and27μA. Sucrose,anthraquinone and quinhydrone added to the cell did not serve to increase the current inthe battery. TiO2electrode, anthraquinone doped graphite electrodes, quinhydrone dopedgraphite electrodes and double-sided graphite electrodes were used respectively as theworking electrode of the cell, and the performance of cells were studied. The results showed that all of these electrodes had the effect of increasing the battery photocurrent.The double-sided graphite electrode was best, it could increase the photocurrent to47.5μA.