Energy storage technologies have attracted great attention as global demand for energy is increasing rapidly. This thesis describes the design strategies of organic materials using bio-inspired peptides and single organic molecules for photochemical and electrical energy storage.
Chapter 1 report the synthesis of self-assembled, insulin-based amyloid nanofibrils that are hybridized with light-responsive dyes (i.e., thioflavin-T, ThT) to mimic natural photosystems. The work presents the potential of self-assembled amyloid nanofibrils as a light-harvesting scaffold for visible light driven NADH regeneration with a biocatalytic module for enzymatic reduction reaction in colloidal system.
Chapter 2 demonstrates visible-light driven regeneration of nicotinamide adenine dinucleotide (NAD+) using solvatochromic Congo red (CR) hybridized with an amyloid-derived peptide (Fmoc-FF) hydrogel system. This study adds a new dimension to the research on self-assembled amyloid materials for biocatalytic oxidized photochemical storage.
Chapter 3 unveils that the proton-coupled redox reaction of a single organic molecule in an aqueous solution can be translated to the lithium-coupled redox reaction of a single organic molecule in a lithium-based organic electrolyte by using phenoxazin-3-one (i.e., resorufin) as a new bio-inspired redox active molecule. The phenoxazin-3-one cathode delivered a high discharge capacity (298 mAh g-1) and fast rate capability (65% capacity retention at 10 C). The result provides insight into the design of a new class of bio-inspired organic electrode materials.
Chapter 4 presents the self-reinforced inductive effect in the symmetric bipolar QA derivative, N,N'-dimethylquinacridone (DMQA), which enables outstanding battery performance in the lithium-ion rechargeable battery system. DMQA, the symmetric bipolar organic molecule, exhibited the excellent battery performance. Excellent capacity retention is achieved at the average voltage of 3.85 V (vs. Li+/Li) and 1.68 V (vs. Li+/Li) during both p- and n-type reaction, which are suitable to work as the cathode and anode of the batteries, respectively. This chapter provides a new insight about energy storage capability of symmetric bipolar organic molecule and its self-reinforced inductive effect.