The ultrafast spatiotemporal imaging of photoexcited electrons is essential to understanding interfacial electron dynamic processes. We used time- and energy-resolved photoemission electron microscopy (PEEM) to investigate the photoexcited electron dynamics at multiplex in-plane silicon pn junctions. We found that the measured kinetic energy of photoelectrons from n-type regions is higher than that from p-type regions owing to different work functions. Interestingly, the kinetic energy of outer n-type regions is higher than that of inner n-type regions, which is caused by the reverse bias induced by photoemission. Time-resolved PEEM results reveal different evolution rates of hot electrons in different doping regions. The rise time of the n-type (outer n-type) regions is faster than that of the p-type (inner n-type) regions. So, closed doping patterns can influence the electron spectra and dynamics at the micro-nano scale. These results help us to understand the ultrafast dynamics of carriers at in-plane interfaces and optimize optoelectronic integrated devices with complex heterojunctions.
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http://dx.doi.org/10.1039/d0nr07954e | DOI Listing |
Nanomaterials (Basel)
January 2025
Department of Physics and Natural Science Research Institute, University of Seoul, Seoul 02504, Republic of Korea.
Bulk n-type SrTiO (STO) has long been known to possess a superconducting ground state at an exceptionally dilute carrier density. This has raised questions about the applicability of the BCS-Eliashberg paradigm with its underlying adiabatic assumption. However, recent experimental reports have set the pairing gap to the critical temperature (Tc) ratio at the BCS value for superconductivity in Nb-doped STO, even though the adiabaticity condition the BCS pairing requires is satisfied over the entire superconducting dome only by the lowest branch of optical phonons.
View Article and Find Full Text PDFACS Omega
January 2025
Department of Physics, Government General Degree College Gopiballavpur-II, Jhargram 721517, India.
Effective engineering of nanostructured materials provides a scope to explore the underlying photoelectric phenomenon completely. A simple cost-effective chemical reduction route is taken to grow nanoparticles of Cd Zn S with varying = 1, 0.7, 0.
View Article and Find Full Text PDFChemistry
January 2025
School of Chemistry and Chemical Engineering/State Key Laboratory Incubation Base for Green Processing of Chemical Engineering, Shihezi University, Xinjiang, 832003, China.
An N,N,N-type Cu(II) complex-catalyzed desaturation method for converting alcohols, ketones, lactones, and lactams to their α,β-unsaturated carbonyl compounds is reported. The dehydrogenation reaction can be conducted with a green terminal oxidant O without requiring strong acid/base or stoichiometric oxidants. The Cu(II) complex/TEMPO/O system uses a non-noble catalyst, and a green terminal oxidant as well as demonstrates high activity and functional group tolerance.
View Article and Find Full Text PDFNutrients
December 2024
Department of Neurosciences, Faculty of Medicine and Nursing, University of the Basque Country UPV/EHU, 48940 Leioa, Spain.
: Omega-3 long-chain polyunsaturated fatty acids (PUFAs) support brain cell membrane integrity and help mitigate synaptic plasticity deficits. The endocannabinoid system (ECS) is integral to synaptic plasticity and regulates various brain functions. While PUFAs influence the ECS, the effects of omega-3 on the ECS, cognition, and behavior in a healthy brain remain unclear.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 311121, P. R. China.
Thermoelectric technology enables the direct and reversible conversion of heat into electrical energy without air pollution. Herein, the stability, electronic structure, and thermoelectric properties of methoxy-functionalized MC(OMe) (M = Sc, Ti, V, Cr, Y, Zr, Nb, Mo, Hf, Ta, and W) were systematically investigated using first-principles calculations and semiclassical Boltzmann transport theory. All MXenes, except those with M = Cr, Mo, and W, can be synthesized by substituting Cl- and Br-functionalized MXenes with deprotonated methanol, with stability governed by the M-O bond strength.
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