Understanding the ultrafast interfacial electron transfer (IET) process is essential for establishing the structure-property relationship of the semiconductor/cocatalyst system for photocatalytic H evolution. However, the IET kinetics for the near bandgap excitation has not been reported. Herein, we investigate the IET kinetics of g-CN/Pt as a semiconductor/cocatalyst prototype by femtosecond time-resolved diffuse reflectance spectroscopy. We find that the near bandgap excitation of g-CN inhibits the IET of g-CN/Pt due to electron deep trapping, resulting in a markedly decreased apparent quantum efficiency for photocatalytic H evolution. This work complements the kinetic understanding for the photocatalytic mechanism of the semiconductor/cocatalyst system in its whole light absorption range.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/acsami.9b20247 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Correlating photochemical H production and excited state lifetimes of heterostructured and doped ZnCdS nanoparticles.
Nanoscale
January 2025
4109 Newman & Wolfrom Laboratory, 100 W 18th Ave, Columbus, OH 43210, USA.
A variety of ZnCdS-based semiconductor nanoparticle heterostructures with extended exciton lifetimes were synthesized to enhance the efficacy of photocatalytic hydrogen production in water. Specifically, doped nanoparticles (NPs), as well as core/shell NPs with and without palladium and platinum co-catalysts, were solubilized into water using various methods to assess their efficacy for solar H fuel synthesis. The best results were obtained with low bandgap ZnCdS cores and ZnCdS/ZnS core/shell NPs with palladium co-catalysts.
View Article and Find Full Text PDFBound-States-in-the-Continuum-Induced Directional Photoluminescence with Polarization Singularity in WS Monolayers.
Nano Lett
January 2025
Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
Monolayer transition metal dichalcogenides are promising materials that not only are atomically thin but also have direct bandgaps, making them highly regarded in optics and optoelectronics. However, their photoluminescence exhibits almost random polarization at room temperature. The emission is also omnidirectional and weak due to the low quantum yield.
View Article and Find Full Text PDFSupercontinuum generation in scintillator crystals.
Sci Rep
January 2025
Laser Research Center, Vilnius University, Saulėtekio Avenue 10, LT-10223, Vilnius, Lithuania.
We present a comparative experimental study of supercontinuum generation in undoped scintillator crystals: bismuth germanate (BGO), yttrium orthosilicate (YSO), lutetium oxyorthosilicate (LSO), lutetium yttrium oxyorthosilicate (LYSO) and gadolinium gallium garnet (GGG), pumped by 180 fs fundamental harmonic pulses of an amplified Yb:KGW laser. In addition to these materials, experiments in yttrium aluminium garnet (YAG), potassium gadolinium tungstate (KGW) and lithium tantalate (LT) were performed under identical experimental settings (focusing geometry and sample thickness), which served for straightforward comparison of supercontinuum generation performances. The threshold and optimal (that produces optimized red-shifted spectral extent) pump pulse energies for supercontinuum generation were evaluated from detailed measurements of spectral broadening dynamics.
View Article and Find Full Text PDFThree-dimensional photoluminescence imaging of threading dislocations in GaN by sub-band optical excitation.
Sci Rep
January 2025
Lawrence Livermore National Lab, Livermore, CA, 94550, USA.
GaN is rapidly gaining attention for implementation in power electronics but is still impacted by its high density of threading dislocations (TDs), which have been shown to facilitate current leakage through devices limiting their performance and reliability. Here, we discuss a novel implementation of photoluminescence (PL) imaging to study TDs in regions within vertically structured p-i-n GaN (PIN) diodes consisting of metalorganic chemical vapor deposition (MOCVD) epitaxial layers grown on ammonothermal GaN (am-GaN) substrates. PL imaging with a sub-bandgap excitation energy (3.
View Article and Find Full Text PDFDirect and Indirect Interfacial Electron Transfer at a Plasmonic p-CuS/CdS Heterojunction.
ACS Nano
January 2025
Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
Plasmonic semiconductors exhibit significant potential for harvesting near-IR solar energy, although their mechanisms of plasmon-induced hot electron transfer (HET) are poorly understood. We report a transient absorption study of plasmon-induced HET in p-CuS/CdS type II heterojunctions. Near-IR excitation of the p-CuS plasmon band at ∼1400 nm leads to ultrafast HET into the CdS conduction band with a time constant of <150 fs and a quantum efficiency of ∼0.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!