Unconventionally anisotropic growth of PbSe nanorods: Controllable fabrication under solution-solid-solid regime over Ag2Se catalysis for broadband photodetection

Abstract

Broadband optoelectronic devices intrigue enormous interests on account of their promising potential in optical communications, sensors and environmental monitoring. PbSe nanocrystals are promising candidates for the construction of next-generation photodetectors due to their fascinating intrinsic properties and solution-processed compatibility with varied substrates. Here, we report the fabrication of a broadband photodetector on the basis of high-quality solution-processed PbSe nanorods in rock-salt phase grown along unconventionally anisotropic growth direction of <112> zone axis. The rock-salt PbSe nanorods are synthesized in solution phase over the catalysis of Ag 2 Se with relatively high-temperature body-centered cubic phase via a solution-solid-solid growth regime using oleylamine and oleic acid as solvents and stabilizer surfactants, from which the PbSe nanorods with the unconventionally anisotropic growth direction are controllably grown in size and shape in the synthetic procedure typically with about 17 nm in diameter and 58 nm in length on average. Meanwhile, the PbSe nanorods-based photodetector exhibits a broadband response from 405 to 1,064 nm with a high responsivity of 0.78 A•W −1 and a fast response time of 17.5 µs. The response time is much faster in comparison with most of the PbSe-based photodetectors with response time in millisecond level.

Photovoltaic–Pyroelectric Coupled Effect in Ag2Se/Si Heterojunction for Broad-Band, Ultrafast, Self-Powered, Position-Sensitive Detectors

“…No additional oxygen peak was found. All experimental data were consistent with previously reported values. ,,, The EDS and XPS results both verified experimentally that the Ag 2 Se films were prepared with high purity.…”

“…Therefore, based on its structural phases, Ag 2 Se is a material of interest for application in numerous fields. However, most previous reports about Ag 2 Se mainly focused on its thermoelectric energy harvesting performance, − , with only a few reports considering the photoelectric performance of Ag 2 Se thin films; ,, in particular, position-sensitive detectors (PSDs) based on Ag 2 Se have not been reported previously.…”

Quasi-Monolayer Ag2Se/1T-WSe2Nanosheets for Enhanced Electrocatalytic Hydrogen Evolution and Charge Storage

“…Figure d,e shows the silver 3d core levels and Auger spectra, respectively. There are two binding energies at 367.74 and 373.74 eV in the Ag 3d spectra of the hybrid nanosheets, which are relevant to 3d 5/2 and 3d 3/2 , respectively . A slight downshifting in binding energies of Ag 3d was observed as compared to the self-contained Ag 2 Se nanocrystals (367.76 and 373.76 eV).…”

“…There are two binding energies at 367.74 and 373.74 eV in the Ag 3d spectra of the hybrid nanosheets, which are relevant to 3d 5/2 and 3d 3/2 , respectively. 20 A slight downshifting in binding energies of Ag 3d was observed as compared to the self-contained Ag 2 Se nanocrystals (367.76 and 373.76 eV). The shifting demonstrates the occurrence of electronic interaction between Ag 2 Se and WSe 2 at the interface/heterojunction in the hybrid nanosheets.…”

“…Ag 2 Se was chosen for coupling with WSe 2 because electrochemically Ag 2 Se exhibits good conductivity along with fast ionic mobility, especially at temperatures over ∼133 °C, − which has also been applied for the catalytic growth of one-dimensional nanostructures and heterostructures using a solution–solid–solid growth regime as initially developed. ,, Taking advantage of its conductive nature and ionic mobility, it can be readily used to remediate poor conducting electroactive materials for energy production and storage purposes. The favorable combination of WSe 2 with Ag 2 Se NPs relieves its aggregation, which reduces the layer density and increases the surface area consequently.…”