4 research outputs found
Development of a Stable MnCo<sub>2</sub>O<sub>4</sub> Cocatalyst for Photocatalytic CO<sub>2</sub> Reduction with Visible Light
The
synthesis of uniform MnCo<sub>2</sub>O<sub>4</sub> microspheres
and their cooperation with a visible light harvester to achieve efficient
photocatalytic CO<sub>2</sub> reduction under ambient conditions are
reported here. The MnCo<sub>2</sub>O<sub>4</sub> materials were prepared
by a facile two-step solvothermal-calcination method and were characterized
by XRD, SEM, TEM, EDX, XPS, elemental mapping, and N<sub>2</sub> adsorption
measurements. By using the MnCo<sub>2</sub>O<sub>4</sub> microspheres
as a heterogeneous cocatalyst, the photocatalytic performance of the
CO<sub>2</sub>-to-CO conversion catalysis was remarkably enhanced,
and no decrease in the promotional effect of the cocatalyst was observed
after repeatedly operating the reaction for six cycles. <sup>13</sup>CO<sub>2</sub> isotope tracer experiments verified that the CO product
originated from the CO<sub>2</sub> reactant. The effect of synthetic
conditions and various reaction parameters on the photocatalytic activity
of the system were investigated and optimized. The stability of the
MnCo<sub>2</sub>O<sub>4</sub> cocatalyst in the CO<sub>2</sub> reduction
system was confirmed by several techniques. Moreover, a possible mechanism
for MnCo<sub>2</sub>O<sub>4</sub>-cocatalyzed CO<sub>2</sub> photoreduction
catalysis is proposed
Supplementary document for The Origination of Chiroptical Effect in Plasmonic Nano-Structures in the View of Quasi-Normal Mode Theory - 6832026.pdf
Supplemental informatio
Hydroxyl-Bonded Ru on Metallic TiN Surface Catalyzing CO<sub>2</sub> Reduction with H<sub>2</sub>O by Infrared Light
Synchronized conversion of CO2 and H2O into
hydrocarbons and oxygen via infrared-ignited photocatalysis remains
a challenge. Herein, the hydroxyl-coordinated single-site Ru is anchored
precisely on the metallic TiN surface by a NaBH4/NaOH reforming
method to construct an infrared-responsive HO-Ru/TiN photocatalyst.
Aberration-corrected high-angle annular dark-field scanning transmission
electron microscopy (ac-HAADF-STEM) and X-ray absorption spectroscopy
(XAS) confirm the atomic distribution of the Ru species. XAS and density
functional theory (DFT) calculations unveil the formation of surface
HO-RuN5–Ti Lewis pair sites, which achieves efficient
CO2 polarization/activation via dual coordination with
the C and O atoms of CO2 on HO-Ru/TiN. Also, implanting
the Ru species on the TiN surface powerfully boosts the separation
and transfer of photoinduced charges. Under infrared irradiation,
the HO-Ru/TiN catalyst shows a superior CO2-to-CO transformation
activity coupled with H2O oxidation to release O2, and the CO2 reduction rate can further be promoted by
about 3-fold under simulated sunlight. With the key reaction intermediates
determined by in situ diffuse reflectance infrared Fourier transform
spectroscopy (DRIFTS) and predicted by DFT simulations, a possible
photoredox mechanism of the CO2 reduction system is proposed
Chiral Plasmonic Shells: High-Performance Metamaterials for Sensitive Chiral Biomolecule Detection
Low-cost and large-area chiral metamaterials (CMs) are
highly desirable
for practical applications in chiral biosensors, nanophotonic chiral
emitters, and beyond. A promising fabrication method takes advantage
of self-assembled colloidal particles, onto which metal patches with
defined orientation are created using glancing angle deposition (GLAD).
However, using this method to make uniform and well-defined CMs over
macroscopic areas is challenging. Here, we fabricate a uniform large-area
colloidal particle array by interface-mediated self-assembly and precisely
control the structural handedness of chiral plasmonic shells (CPSs)
using GLAD. Strong chiroptical signals arise from twisted currents
at the main, corner, and edge of CPSs, allowing a balance between
strong chiroptical and high transmittance properties. Our shell-like
chiral geometry shows excellent sensor performance in detecting chiral
molecules due to the formation of uniform superchiral fields. Systematic
investigations optimize the interplay between peak and null point
resonances in different CPSs and result in a record consistency chiral
sensor parameter U, i.e., 3.77 for null points and
0.0867 for peaks, which are about 54 and 1.257 times larger than the
highest value (0.068) of previously reported CMs. The geometrical
chirality, surface plasmonic resonance, chiral surface lattice resonance,
and chiral sensor performance evidence the chiroptical effect and
the excellent chiral sensor performance