Professor Robert Taylor

Abstract:

The updated data files are supporting demonstration of weak coupling between a cavity mode and emission from a single quantum dot. In this research (done by January 2020) we developed an easily controlled fabrication process to deterministically write a mode gap cavity over a photonics crystal waveguide. All data files uploaded here are obtained through micro-photoluminescence(PL) experiments. Those associated with 'fig4' are the single time-integrated PL spectra with the first column in the data file being wavelength in 'nm'. fig4 a and b are single PL spectra of high and low density of ensemble quantum dots emission before coating the cavity. fig4 c is showing the crossover between the cavity emission mode and the quantum dot spectrum over a temperature run. fig 5 is the time-resolved PL data of three different temperatures demonstrating Purcell enhancement. The corresponding first column represents time and is in the unit of 'ns'. NB: This is Version 1 of the data and has been superseded by Version 2 at https://doi.org/10.5287/bodleian:ErJbzzO84

Abstract:

Photocatalytic water splitting is attracting enormous interest for the storage of solar energy but no practical method has yet been identified. In the past decades, various systems have been developed but most of them suffer from low activities, a narrow range of absorption and poor quantum efficiencies (Q.E.) due to fast recombination of charge carriers. Here we report a dramatic suppression of electron-hole pair recombination on the surface of N-doped TiO2 based nanocatalysts under enhanced concentrations of H+ and OH−, and local electric field polarization of a MgO (111) support during photolysis of water at elevated temperatures. Thus, a broad optical absorption is seen, producing O2 and H2 in a 1:2 molar ratio with a H2 evolution rate of over 11,000 μmol g−1 h−1 without any sacrificial reagents at 270 °C. An exceptional range of Q.E. from 81.8% at 437 nm to 3.2% at 1000 nm is also reported.