Hollow Cu2-xS@NiFe Layered Double Hydroxide Core-Shell S-Scheme Heterojunctions with Broad-Spectrum Response and Enhanced Photothermal-Photocatalytic Performance

Plasmon-mediated dual S-scheme charge transfer in Cu2-xS/In2S3/Bi2S3 hollow polyhedrons for efficient Photothermal-Assisted photocatalysis

Step-scheme (S-scheme) semiconductor junction has garnered considerable attention for its potential applications in photocatalytic energy conversion. However, the photocatalytic activity of S-scheme junctions is restricted by inadequate light absorption and low charge separation efficiency. Herein, a plasmon-mediated dual S-scheme junction is constructed by growing In2S3 and Bi2S3 nanoparticles on Cu2-xS hollow polyhedrons, exhibiting efficient photothermal-assisted photocatalysis. Due to the unique hollow polyhedron structure, the plasmon resonance, and the bandgap excitation, the Cu2-xS/In2S3/Bi2S3 hybrids show broad light absorption. Meanwhile, the plasmon-mediated dual S-scheme charge transfer, including the injection of plasmon-induced hot electrons from Cu2-xS to In2S3 and Bi2S3 as well as the transfer of plasmon-induced hot holes from the trap states of Cu2-xS to In2S3 and Bi2S3, enables the hybrids to have efficient charge separation. In addition, remarkable photothermal performance originates from the synergistic effect of plasmonic heating and lattice thermal vibration, which leads to a further increase in the local temperature and enhancement of charge transfer efficiency in the hybrids. As a result, the Cu2-xS/In2S3/Bi2S3 hybrids demonstrate outstanding performance in photothermal-assisted photocatalytic hydrogen generation, rivaling many similar photocatalysts. This work offers valuable insights for designing high-efficiency photocatalysts based on S-scheme junctions.

Strong interaction between plasmon and topological surface state in Bi2Se3/Cu2-xS nanowires for solar-driven photothermal applications

Developing high-performance photothermal materials and unraveling the underlying mechanism are essential for photothermal applications. Here, photothermal performance improved by strong interaction between plasmon and topological surface state (TSS) is demonstrated in Bi2Se3/Cu2-xS nanowires. This hybrid, which Cu2-xS nanosheets were grown on Bi2Se3 nanowires, leverages the plasmon resonance and TSS-induced optical property, generating wide and efficient light absorption. A series of tests reveals the strong resonance coupling, TSS-induced hot electron injection, and plasmon-induced hot hole relaxation within the hybrids, endowing the Bi2Se3/Cu2-xS with excellent photothermal performance. By integrating the hybrids into a hydrogel with a thermoelectric module, the Bi2Se3/Cu2-xS evaporator achieves a remarkable water evaporation rate of 3.67 kilograms per square meter per hour with a solar-to-vapor efficiency of 95.2%, and a maximum output power of 1.078 watts per square meter under simulated sunlight irradiation. Moreover, a conical mirror was introduced to the device, which greatly enhances the evaporation rate and maximum output power without additional energy input.

Photothermal-catalytic activation periodate over MnO2/g-C3N4 S-scheme heterojunction for rapidly tetracycline removal: intermediates, toxicity evaluation and mechanism

The MnO2/CN S-scheme heterojunctions were prepared using the hydrothermal method, which significantly promoted periodate (PI) activation for the TC removal. Notably, the MnO2/CN-0.1 achieved a TC removal rate of 79.7 % within 25 min in the PI/Vis system, which was 1.39 and 3.68 times that of MnO2 and g-C3N4, respectively. The improved TC degradation performance could be attributed to the synergetic effect of photothermal effect of MnO2 and the S-scheme heterojunction. On the basis of the infrared thermography images, the photothermal properties of MnO2 could increase temperatures of the reaction system, leading to the promotion of the PI activation. The formation of the MnO2/CN S-scheme not only effectively suppressed charge recombination, but also facilitated the Mn(IV)/Mn(III) redox cycle within the reaction. Under different pH and anion conditions, the MnO2/CN-0.1/PI system exhibited excellent capability in TC removal. Additionally, the toxicity of the degraded solution was evaluated based on the LC-MS test results and the growth experiment of Mung bean seeds. This work put forward an efficient approach on S-scheme photothermal catalysts to achieve efficient utilization of PI on TC degradation, which demonstrates a promising method for photothermal assistance PI activation to remediate the water environment efficiently.

p-n-Type LaCoO3/NiFe LDH Heterostructures for Enhanced Photogenerated Carrier-Assisted Electrocatalytic Oxygen Evolution Reaction

The oxygen evolution reaction (OER) poses a significant kinetic challenge for various critical energy conversion and storage technologies including electrocatalytic water splitting and metal-air batteries. In this study, a LaCoO3/NiFe layered double hydroxide (LDH) catalyst was synthesized through the in situ growth of n-type NiFe LDH on the surface of the p-type LaCoO3 semiconductor, resulting in a p-n heterostructure for a photogenerated carrier-assisted electrocatalytic OER (PCA-eOER). The alignment of their band structures facilitates the formation of an internal electric field at the heterojunction interface, which promotes the creation of oxygen vacancies and enhances electron transport. Under illumination, the expanded visible-light absorption range and built-in electric field work synergistically to improve the generation and separation of photogenerated carriers. Meanwhile, the accumulation of photogenerated holes on the surface of NiFe LDH results in an enhancement in the concentration of high-valent active metal sites, resulting in a boost in the PCA-eOER efficiency. The LaCoO3/NiFe LDH has achieved an overpotential of 260 mV at the current density of 10 mA cm-2, 50 mV lower than in the absence of illumination. In addition, LaCoO3/NiFe LDH was assembled into an alkaline water electrolyzer and zinc-air batteries (ZABs), showing excellent practical application capability. We explored the application of LaCoO3 in a PCA-eOER, which provides a concept for designing PCA-eOER catalysts and advancing the development of perovskite-based catalysts for clean energy conversion technology.

MIL-125-PDI/ZnIn2S4 Inorganic-Organic S-Scheme Heterojunction With Hierarchical Hollow Nanodisc Structure for Efficient Hydrogen Evolution from Antibiotic Wastewater Remediation

Efficient photocatalytic production of H2 from wastewater is expected to address environmental pollution and energy crises effectively. However, the rapid recombination of photoinduced carriers results in low photoconversion efficiency. At present, inorganic-organic S-scheme heterojunction have become a prominent and promising technology. In this study, an organic ligand modified MIL-125-PDI/ZnIn2S4 (ZIS) inorganic-organic S-scheme heterojunction catalyst is designed. ZIS nanosheets are grown on the disc-shaped MIL-125-PDI surface to form a distinctive hollow nanodiscs with hierarchical structure, giving the material an abundance of surface active sites, an optimized electronic structure, and a spatially separated redox surface. Consequently, the optimal 100MIL-125-PDI250/ZIS exhibited high photocatalytic HER of 508.99 µmol g-1 h-1 in Tetracycline hydrochloride (TC-HCl) solution. Meanwhile, the catalyst achieved complete TC-HCl removal and mineralization rate of 66.62% in 4 h. Experimental and theoretical calculations corroborate that the staggered band alignment and work function difference between MIL-125-PDI and ZIS induce the formation of a built-in electric field, thus regulating the charge transfer routes and consequently enhancing charge separation efficiency. The possible photocatalytic mechanism is analyzed using liquid chromatography-mass spectrometry (LC-MS), and the toxicities of the degradation products are also evaluated. This work presents a green dual-function strategy for H2 production and antibiotic wastewater recycling.

Dual-mode detection for the total antioxidant capability of skincare products based on porous CuS@CdS@Au nanoshells

The antioxidants in skincare products play a crucial role in delaying the aging process of the skin. With the growing variety of cosmetic products, it is essential to develop effective methods for measuring their total antioxidant capability (TAC). This study introduces a novel nanoenyzme, CuS@CdS@Au nanoshells (NSs), characterized by porous morphologies and composite materials, which demonstrate remarkable localized surface plasmon resonance (LSPR) effects, thereby enhancing their photocatalytic and photothermal properties. Under 808 nm laser irradiation, these nano-enzymes exhibited superior catalytic ability for TMB oxidation and temperature increases compared to CuS or CuS @Au NSs. The TMB absorption response and temperature increase showed high sensitivity to antioxidants such as ascorbic acid, glutathione, and ferulic acid, enabling the development of a dual-mode detection strategy for quantifying the TAC in skincare products without the need for complex pretreatments. Furthermore, the temperature response-based detection results proved to be more accurate than those derived from absorption response in recovery experiments. This research not only improves the reliability of antioxidant assessments but also provides a valuable tool for quality control in the skincare industry.

Progress and Challenges of Ferrite Matrix Microwave Absorption Materials

Intelligent devices, when subjected to multiple interactions, tend to generate electromagnetic pollution, which can disrupt the normal functioning of electronic components. Ferrite, which acts as a microwave-absorbing material (MAM), offers a promising strategy to overcome this issue. To further enhance the microwave absorption properties of ferrite MAM, numerous works have been conducted, including ion doping and combining with other materials. Notably, the microstructure is also key factor that affects the microwave absorption properties of ferrite-based MAM. Thus, this article provides a comprehensive overview of research progress on the influence of the microstructure on ferrite-based MAM. MAMs with sheet and layered structures are also current important research directions. For core-shell structure composites, the solid core-shell structure, hollow core-shell structure, yolk-eggshell structure, and non-spherical core-shell structure are introduced. For porous composites, the biomass porous structure and other porous structures are presented. Finally, the development trends are summarized, and prospects for the structure design and preparation of high-performance MAMs are predicted.