Gold Nanoparticle Interaction in Algae Enhancing Quantum Efficiency and Power Generation in Microphotosynthetic Power Cells

Abstract

The necessity for sustainable energy production has driven the rapid development of technologies to harness solar energy effectively. The microphotosynthetic power cells (μPSC) aim to harness solar energy from living photosynthetic cells. Currently, the power density of the μPSC is low, due to several factors. One of the major impediments and challenges of the μPSC is its lower charge transfer efficiency between the photosynthetic microorganisms and the electrodes. Herein, the proposed strategy explores the interaction of gold nanoparticles (Au NPs) with photosynthetic microorganisms for enhanced power generation from the μPSC. Herein, the intracellular biocompatible, efficient light absorbers in the form of Au NPs are introduced. Translocation of gold colloidal solution of 25 μL of 50 μg mL−1 (253.8 μmol mL−1) concentration into 2 mL whole liquid culture of algal cells (Chlamydomonas reinhardtii: ≈1 million cells mL−1) enhances operational quantum yield (ϕ0) of the algal cells by 30.2% and power generation capability by 15.2% in μPSCs. Internalized Au NPs in the algal cells quench chlorophyll fluorescence, thereby contributing to increased photosynthetic efficiency. With multiple advantages such as light absorption capability, biocompatibility, and ability to transfer the electrons, Au NPs can efficiently harvest sunlight for enhanced power generation from the μPSC.

Keywords

• algal cells
• bioelectricity
• biophotovoltaics
• biosolar cells
• electron transfers
• gold nanoparticles