Promoting Photon-to-Chemical Conversion through a Dielectric Antenna-Hybrid Bilayered Reactor Configuration.

The application of scattered light via an antenna-reactor configuration is promising for converting thermocatalysts into photocatalysts. However, the efficiency of dielectric antennas in photon-to-chemical conversion remains suboptimal. Herein, we present an effective approach to promote light utilization efficiency by designing dielectric antenna-hybrid bilayered reactors. Experimental studies and finite-difference time-domain simulations demonstrate that the engineered SiO2-carbon/metal dielectric antenna-hybrid bilayered reactors exhibit a synergy of absorption superposition and electric field confinement between carbon and metals, leading to the improved absorption of scattered light, upgraded charge carriers density, and ultimately promoted photoactivity in hydrogenating chlorobenzene with an average benzene formation rate of 18 258 µmol g-1 h-1, outperforming the reported results. Notably, the carbon interlayer proves to be more effective than the commonly explored dielectric TiO2 interlayer in boosting the benzene formation rate by over 3 times. This research paves the way for promoting near-field scattered photon-to-chemical conversion through a dielectric antenna-hybrid reactor configuration.

Engineering the Metal/Dielectric Interface to Unlock the Potential of Scattered Light for Boosted Photoredox Catalysis.

The recycling of scattered light by metals has been emerging as a promising light-manipulation-capture strategy, but how to bring its potential into better play remains to be explored. Herein, we present that constructing dual metal/high-refractive-index dielectric interfaces within the SiO2 core@TiO2 shell-Pd satellite@TiO2 shell effectively strengthens both the scattering efficiency of the dielectric SiO2 support and electric field confinement. Consequently, the absorption of Pd toward near-field scattered light and the interfacial charge carrier separation are both enhanced. The synergy of these effects leads to boosted photoactivity toward the aerobic oxidation of cyclohexanol to cyclohexanone and the anaerobic reduction of proton for hydrogen evolution under visible-light irradiation as compared to the counterparts with a single metal/dielectric interface and dual metal/dielectric interfaces consisting of low-refractive-index dielectric component. Notably, the similar enhancements in both optical absorption and photoactivity can be achieved through the present dual metal/high-refractive-index dielectric interfaces engineering strategy for other metals, such as Pt nanoparticles. This work presents an instructive avenue to upgrade the optical response of metals and thus the photocatalytic performance by engineering metal/dielectric interfaces.

Elbaite catalyze peroxymonosulfate for advanced oxidation of organic pollutants: Hydroxyl groups induced generation of reactive oxygen species.

In this work, the abundant, low-cost, innocuous, and chemically stable elbaite (a type of tourmaline) was employed to catalyze peroxymonosulfate (PMS) for wastewater purification by using methylene blue (MB) as one of the target pollutants. The results revealed that PMS could be catalyzed by elbaite within broad pH range (i.e., 2.9-10.7) and with low activation energy (i.e., 18.6 kJ/mol). Complete MB degradation was obtained within 15 min under the optimized conditions: [elbaite]0 = 1.00 g/L, [PMS]0 = 0.50 g/L, initial solution pH = 2.9. MB degradation (%) sustained 99.9 % after five successive catalytic reactions, indicating good durability and long-term stability. In addition, the complete degradation of doxycycline hydrochloride (DOX) and bisphenol A (BPA) further confirmed the degradation activity of the PMS/elbaite system. PMS interacted with elbaite via replacing the surface-bonded and structural OH groups of elbaite with its OH groups to bond with YLiYAlYR and YLiZAlZR cations (R = Al, Li, Fe, Mg, Mn, Cr, V), which offered channels for electron transfer from negatively charged elbaite to PMS, leading to the activation of PMS. Thus, elbaite is found to be promising for catalyzing PMS to treat organic wastewater.

Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts.

Photocatalysis is considered to be a green and promising technology for transforming organic contaminants into nontoxic products. In this work, a CuO/tourmaline composite with zero-dimensional/two-dimensional (0D/2D) CuO architecture was successfully obtained via a facile hydrothermal process, and its photocatalytic activity was evaluated by the degradation of methylene blue (MB). Surface element valence state and molecular vibration characterization revealed that CuO chemically interacted with tourmaline via Si-O-Cu bonds. The specific surface area of the CuO/tourmaline composite (23.60 m2 g-1) was larger than that of the pristine CuO sample (3.41 m2 g-1). The CuO/tourmaline composite exhibited excellent photocatalytic activity for the degradation of MB, which was ascribed to the increase in the quantity of the adsorption-photoreactive sites and the efficient utilization of the photoinduced charge carriers. This study provides a facile strategy for the construction of 0D/2D CuO structures and the design of tourmaline-based functional composite photocatalysts for the treatment of organic contaminants in water.