Time-resolved photoluminescence of Zn(OH)_2 and its composites with graphite oxides

Abstract

Time-resolved photoluminescence is used to determine carrier recombination through radiative and nonradiative processes in zinc hydroxide Zn(OH)(2) and its porous composites with graphite oxide (GO). The decay times, measured by a streak camera, are found to be larger for zinc hydroxide (~1215±156 ps) than its composites (~976±81 ps for ZnGO-2 and 742±59 ps for ZnGO-5), but no significant changes in rise times (from 4.0 to 5.0 ps) are recorded. The dominant mechanism for the radiative process is attributed to free carrier recombination, while microporous networks present in these materials are found to be pathways for the nonradiative recombination process via multiphonon emission.

The effects of fabrication temperature on current-voltage characteristics and energy efficiencies of quantum dot sensitized ZnOH-GO hybrid solar cells

“…The morphologies of zinc (hydr)oxide and its composites were previously reported using the images obtained by Two Photon Fluorescence (TPF) Microscopy, Scanning Electron Microscopy (SEM), and Scanning Tunneling Microscopy (STEM). [8][9][10][11] Third, graphite-oxide (GO) was synthesized by oxidation of graphite (Sigma-Aldrich) using Hummers method, detailed elsewhere. 8,12 Fourth, prior to chemical synthesis of ZnOH-GO composites, the structures of the precursor materials were investigated.…”

“…Using this imaging technique, particle size and their distribution were reported earlier. [9][10][11] TPF imaging was performed with the Ultima Multi-Photon-Microscope (Olympus BX-51 of Prairie Tech. Inc., WI, USA).…”

Sharpness-enhanced ultrafast imaging by using a biased optical Kerr gate

“…Ultrafast imaging provides an interesting tool applied in fields as diverse as medical imaging, fluid dynamics, and material science. The temporal resolution of the ultrafast imaging system is determined by the exposure time of the camera, which can be electronically gated on the timescale of picoseconds [1] and even faster by driving the time gate optically. Until now holography and various nonlinear optics effects, such as second harmonic generation [2,3], stimulated Raman amplification [4] and the optical Kerr gate (OKG) [5], have been investigated for ultrafast time gating.…”