Visualization 2.mp4

The rendering process of Fig. 4(a)-4(d

Visualization 1.avi

Related to Fig.

Visualization 1.mp4

The resulting 4D image for a 10-µm fluorescent bea

Visualization 2.avi

Rendering process of the volumetric images using the 21 TFMI-LFM, TF-MPEM, and point-scanning MPEM image

Visualization 3.mp4

The rendering process of Fig. 5(a), 5(b), 5(d), and 5(f

Visualization 1.avi

Brownian motion of a 2-µm florescent bead in water with a volumetric imaging rate of 100 H

Tuning the Electronic Structure of Graphite Oxide through Ammonia Treatment for Photocatalytic Generation of H₂ and O₂ from Water Splitting

Graphite oxide (GO) synthesized from the oxidation of graphite powders exhibits p-type conductivity and is active in photocatalytic H₂ evolution from water decomposition. The p-type conductivity hinders hole transfer for water oxidation and suppresses O₂ evolution. Treating GO with NH₃ gas at room temperature tunes the electronic structure by introducing amino and amide groups to its surface. The ammonia-modified GO (NGO) exhibits n-type conductivity in photoelectrochemical analysis and has a narrower optical band gap than GO. Electrochemical analysis attributes the band gap reduction to a negative shift of the valence band. An NGO-film electrode exhibits a substantially higher incident photo-to-current efficiency in the visible light region than a GO electrode. Photoluminescence analyses demonstrate the above-edge emission characteristic of GO and NGO. NH₃ treatment enhances the emission by removing nonirradiative epoxy and carboxyl sites on the GO. In half-reaction tests of water decomposition, NGO effectively catalyzes O₂ evolution in an aqueous AgNO₃ solution under mercury-lamp irradiation, whereas GO is inactive. NGO also effectively catalyzes H₂ evolution in an aqueous methanol solution but shows less activity than GO. Under illumination with visible light (λ > 420 nm), NGO simultaneously catalyzes H₂ and O₂ evolutions, but with a H₂/O₂ molar ratio below 2. The n-type conductivity of NGO may hinder electron transfer and form peroxide species instead of H₂ molecules. This study demonstrates that the functionality engineering of GO is a promising technique to synthesize an industrially scalable photocatalyst for overall water splitting

Media 2: Photophysical mechanisms of collagen modification by 80 MHz femtosecond laser

Originally published in Optics Express on 08 November 2010 (oe-18-23-24037

Media 1: Photophysical mechanisms of collagen modification by 80 MHz femtosecond laser

Originally published in Optics Express on 08 November 2010 (oe-18-23-24037

Media 3: Photophysical mechanisms of collagen modification by 80 MHz femtosecond laser

Originally published in Optics Express on 08 November 2010 (oe-18-23-24037