Ultrasonic-enhanced photocatalysis through piezoelectric and cavitation effects for lignin depolymerization.

Although a promising method for lignin depolymerization, photocatalysis faces the challenge of low efficiency. In this study, MoS2/ZnO heterojunction catalysts, endowed with piezocatalysis and photocatalytic capabilities, were crafted through Zn ion intercalation for the depolymerization of phenoxyphenylethanol (PP-ol) and alkali lignin. Then, the synergistic interplay between ultrasonic-induced piezoelectric fields and heterojunctions was analyzed. The amalgamation of the piezoelectric field and heterojunction in MoS2/ZnO catalysts resulted in a diminished photogenerated hole/electron recombination efficiency, thereby fostering the generation of ·OH during the reaction. This pivotal role of ·OH emerged as a crucial reactive substance, converting 95.8 % of PP-ol through ß-O-4 bond breaking within a 3-h treatment. By incorporating ultrasonic, the contact probability of PP-ol with the catalyst was significantly improved, resulting in efficient conversion even with a reduced amount of acetonitrile in the solvent system (20 %). Furthermore, ultrasonic-light methods show high efficiency for depolymerizing Alkali lignin (AL), with 33.2 % of lignin undergoing depolymerization in a 4-h treatment. This treatment simultaneously reduces the molecular weight of AL and cleaves numerous chemical bonds within it. Overall, this work presents a green approach to lignin depolymerization, providing insights into the synergistic action of ultrasonic and photocatalysis.

Transient paper-based electrochemical biosensor Fabricated by superadditive Cu-TCPP(Fe)/Mxene for Multipathway non-invasive, highly sensitive detection of Bodily metabolites.

Current advances in non-invasive fluid diagnostics highlight unique benefits for monitoring metabolic diseases. However, the low concentrations and complex compositions of biomarkers in fluids such as sweat, urine, and saliva impose stringent demands on the sensitivity and stability of detection technologies. Here, we developed a high-sensitivity, low-cost instantaneous electrochemical sensor based on the superadditive effect mechanism of Cu-TCPP(Fe)/Mxene (MMs Paper-ECL Sensor), which has been successfully applied for the simultaneous real-time detection of glucose and uric acid. Strong interfacial interactions between Mxene and Cu-TCPP(Fe) were revealed through precise simulation calculations and multi-dimensional characterization analysis, significantly enhancing the sensor's electrocatalytic performance and reaction kinetics. Experimentally, this exceptional electrocatalytic activity was demonstrated in its unprecedented high sensitivity and wide linear detection range for glucose and uric acid, with a non-invasive linear range from 0.001 nM to 5 mM, 0.025 nM-5 mM, detection limits as low as 1.88 aM and 5.80 pM, and stability extending up to 100 days. This represents not only a breakthrough in sensitivity and stability but also provides an effective, low-cost solution that overcomes the limitations of existing electronic devices, enabling multi-channel simultaneous detection. The universality of this sensor holds vast potential for application in the field of non-invasive fluid diagnostics.

Reversible Regulation of the Reactive Oxygen Species Level Using a Semiconductor Heterojunction.

Here, we proposed a novel solution for reversible regulation of the reactive oxygen species (ROS) level using a semiconductor heterojunction. Two metal-based ROS scavengers containing n-type CeO2 nanoparticles and n-type Cu-doped diatom biosilica (Cu-DBs) were integrated by a hydrothermal method to form a typical n-n semiconductor heterojunction (Ce/Cu-DBs). Unlike the control of the ROS level by a single ROS scavenger or ROS-generating agent, Ce/Cu-DBs could quickly eliminate ROS by cascade catalytic reaction, which readily switched to ROS generation through a near-infrared (NIR)-triggered photocatalytic effect. This NIR mediated ROS regulation system provided a noninvasive strategy for reversible control of the ROS level in vitro and in vivo. The Ce/Cu-DBs could relieve cellular oxidative stress by clearing local excessive ROS while inhibiting bacterial growth by increasing ROS levels under NIR radiation. Benefiting from the reversible regulatory effect of Ce/Cu-DBs, programmable healing of infected wounds was realized via on-demand anti-infection and inflammation reduction. This work provided a general method with highly spatiotemporal resolution to a remote and sustainable control ROS level, which had great potential for the biomedical field and regulation of chemical reactions.

Coverage Layer Phase Composition-Dependent Photoactivity of One-Dimensional TiO2-Bi2O3 Composites.

TiO2-Bi2O3 composite rods were synthesized by combining hydrothermal growth of rutile TiO2 rod templates and sputtering deposition of Bi2O3 thin films. The TiO2-Bi2O3 composite rods with ß-Bi2O3 phase and α/ß-Bi2O3 dual-phase decoration layers were designed, respectively, via in situ radio-frequency magnetron sputtering growth and post-annealing procedures in ambient air. The crystal structure, surface morphology, and photo-absorption performances of the pristine TiO2 rods decorated with various Bi2O3 phases were investigated. The crystal structure analysis reveals that the crystalline TiO2-Bi2O3 rods contained ß-Bi2O3 and α/ß-Bi2O3 crystallites were separately formed on the TiO2 rod templates with different synthesis approaches. The morphology analysis demonstrates that the ß-Bi2O3 coverage layer on the crystalline rutile TiO2 rods showed flat layer morphology; however, the surface morphology of the α/ß-Bi2O3 dual-phase coverage layer on the TiO2 rods exhibited a sheet-like feature. The results of photocatalytic decomposition towards methyl orange dyes show that the substantially improved photoactivity of the rutile TiO2 rods was achieved by decorating a thin sheet-like α/ß-Bi2O3 coverage layer. The effectively photoinduced charge separation efficiency in the stepped energy band configuration in the composite rods made from the TiO2 and α/ß-Bi2O3 explained their markedly improved photoactivity. The TiO2-α/ß-Bi2O3 composite rods are promising for use as photocatalysts and photoelectrodes.

Recent Advances in 2D Lateral Heterostructures.

Recent developments in synthesis and nanofabrication technologies offer the tantalizing prospect of realizing various applications from two-dimensional (2D) materials. A revolutionary development is to flexibly construct many different kinds of heterostructures with a diversity of 2D materials. These 2D heterostructures play an important role in semiconductor and condensed matter physics studies and are promising candidates for new device designs in the fields of integrated circuits and quantum sciences. Theoretical and experimental studies have focused on both vertical and lateral 2D heterostructures; the lateral heterostructures are considered to be easier for planner integration and exhibit unique electronic and photoelectronic properties. In this review, we give a summary of the properties of lateral heterostructures with homogeneous junction and heterogeneous junction, where the homogeneous junctions have the same host materials and the heterogeneous junctions are combined with different materials. Afterward, we discuss the applications and experimental synthesis of lateral 2D heterostructures. Moreover, a perspective on lateral 2D heterostructures is given at the end.

2D/1D Zn0.7Cd0.3S p-n heterogeneous junction enhanced with NiWO4 for efficient photocatalytic hydrogen evolution.

Bimetallic solid solutions have attracted much attention in the field of photocatalysis due to their excellent photocatalytic properties. Here, Zn0.7Cd0.3S solid solution with two morphologies was prepared by typical solvent-thermal method. The co-existence of 1D rod-like Zn0.7Cd0.3S and 2D sheet-like Zn0.7Cd0.3S can be found in SEM and TEM diagrams. This special structure can provide a larger specific surface area for exposing more active sites and expanding optical contact surface, which is favorable for boosting photocatalytic water-splitting reaction. In addition, a p-n junction formed by the interface contact between NiWO4 and Zn0.7Cd0.3S effectively promotes the transfer of interfacial charges through the built-in electric field, and thus recombination of the electron-hole pairs is greatly inhibited. The highest photocatalytic H2 production rate in the Na2S/Na2SO3 system is 15.95 mmol h-1 g-1, which is 3.16 times higher than the bare Zn0.7Cd0.3S. Meanwhile, Mott-Schottky curves further confirmed the Zn0.7Cd0.3S and NiWO4 suitable conduction band and valence band position, forming a more effective thermodynamic charge transfer path. This work provides for the first time 2D/1D structure of Zn0.7Cd0.3S and highlights the more efficient photocatalytic hydrogen evolution performance of the p-n junction in Zn0.7Cd0.3S/NiWO4.