There are numerous sources of bioenergy that are generated by photosynthetic processes, for example, lipids, alcohols, hydrogen, and polysaccharides. However, generally only a small fraction of solar energy absorbed by photosynthetic organisms is converted to a form of energy that can be readily exploited. To more efficiently use the solar energy harvested by photosynthetic organisms, we evaluated the feasibility of generating bioelectricity by directly extracting electrons from the photosynthetic electron transport chain before they are used to fix CO(2) into sugars and polysaccharides. From a living algal cell, Chlamydomonas reinhardtii, photosynthetic electrons (1.2 pA at 6000 mA/m(2)) were directly extracted without a mediator electron carrier by inserting a nanoelectrode into the algal chloroplast and applying an overvoltage. This result may represent an initial step in generating "high efficiency" bioelectricity by directly harvesting high energy photosynthetic electrons.

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Slurry for lithium-ion batteries is prepared from an active material, a carbon conductive additive, and a polymeric binder in a solvent, and its morphological change is evaluated over time using electrochemical impedance spectroscopy. A schematic model of the internal structure and dispersion states of the slurry components during 7 days of storage is proposed on the basis of the electrochemical impedance spectroscopy (EIS) measurement. The EIS results reveal that the conductive path constructed by the network structure of the slurry components breaks over time, which can be worsened by mechanical agitation. In order to confirm the morphological change, the slurry is freeze-dried and then prepared to fixate the locations of the slurry components. The existence of a network structure (or flocculation) is verified by morphological observations. In addition, the dispersity index and Micro-CT are introduced as new methods representing the dispersion state of the slurry components.

The oxygen evolution of single cells was investigated using a nano-probe with an ultra-micro electrode (UME) in a submicron sized system in combination with a micro-fluidic system. A single cell was immobilized in the micro-fluidic system and a nano-probe was inserted into the cytosolic space of the single cell. Then, the UME was used for an in vivo amperometric experiment at a fixed potential and electrochemical impedance spectroscopy to detect oxygen evolution of the single cell under various light intensities.