Ultrathin Structure Research Articles

Next-generation of a Fe-Ce double variable-valence metals modulated high-efficiency nanozyme

High catalytic efficiency is the continuous pursuit for the preparation of high-performance nanozymes. In this work, a Fe-Ce double variable-valence metals nanozyme (Fe-Ce-MOL) was constructed based on metal–organic layers (MOLs), a class of two-dimensional metal–organic frameworks with ultra-thin structure, for peroxidase (POD) mimicking. Fe-Ce-MOL exhibited significantly enhanced catalytic activity in comparison with that of natural horseradish peroxidase and single variable-valence metal nanozyme (Fe-Zr-MOL). Density functional theory calculations demonstrated that the Fe site of Fe-Ce-MOL had a stronger adsorption effect on H2O2 compared to Fe-Zr-MOL and more heat was released in the catalytic reaction of H2O2, making the reaction easier to occur. Moreover, there was more electron transfer between Fe and Ce double variable-valence metals, also accelerating the catalytic process. These results indicated that the ultra-thin structure of Fe-Ce-MOL provided more catalytic sites and Fe and Ce double variable-valence metals could regulate the process of oxidation–reduction and promote the efficiency of electron transfer synergistically. As a proof of concept, the proposed Fe-Ce-MOL was used in biosensing and antibacterial applications. These results suggested that Fe-Ce-MOL had great potential as a new-generation nanozyme. This work pioneers a new approach for the rational design of highly efficient nanozymes.

Thermal recombination strategy designed R-CN as active shell to improve catalyst activity

A new recombinant CN material (R-CN) was prepared with g-C3N4 as precursor by hydrothermal method combined with thermal recombination method, which has 2D ultra-thin structure, nanoscale folds, graphite-like texture and some pores, and has richer N and O elements than g-C3N4. R-CN can reduce high temperature decomposition peak of ammonium perchlorate (AP) to 356.06 oC, and its promoting effect is obviously better than that of g-C3N4. Based on specific structural composition and physicochemical properties of R-CN, a novel R-CN@MWO composite with core-shell was designed, which was applied to catalytic decomposition of AP and pressure enlarging effect during combustion process of cyclotrimethylenetrinitramine (RDX)+nitrocellulose (NC). With the introduction of R-CN@MWO, decomposition peak temperature and activation energy of AP are reduced by 104.67oC and 59.24 kJ mol−1, and peak pressure and pressurization rate of RDX+NC constant volume combustion test are increased by 11.33 and 118.54 times, respectively. Moreover, the combustion rate of R-CN@MWO-AP/HTPB propellant is 3.23 times that of AP/HTPB propellant. To sum up, R-CN as a coating layer can significantly enhance catalytic activity of MgWO4 for thermal decomposition of energetic materials.

Black Ultrathin Single-Crystalline Flakes of CuVP2S6 and CuCrP2S6 for Near-Infrared-Driven Photocatalytic Hydrogen Evolution.

The development of new near-infrared-responsive photocatalysts is a fascinating and challenging approach to acquire high photocatalytic hydrogen evolution (PHE) performance. Herein, near-infrared-responsive black CuVP2S6 and CuCrP2S6 flakes, as well as CuInP2S6 flakes, are designed and constructed for PHE. Atom-resolved scanning transmission electron microscopy images and X-ray absorption fine structure evidence the formation of ultrathin single-crystalline sheet-like structure of CuVP2S6 and CuCrP2S6. The synthetic CuVP2S6 and CuCrP2S6, with a narrow bandgap of ≈1.0eV, shows the high light-absorption edge exceeding 1100nm. Moreover, through the femtosecond-resolved transient absorption spectroscopy, CuCrP2S6 displays the efficient charge transfer and long charge lifetime (18318.1ps), which is nearly 3 and 29 times longer than that of CuVP2S6 and CuInP2S6, respectively. In addition, CuCrP2S6, with the appropriate d-band and p-band, is thermodynamically favorable for the H+ adsorption and H2 desorption by contrast with CuVP2S6 and CuInP2S6. As a result, CuCrP2S6 exhibits high PHE rates of 9.12 and 0.66mmol h-1 g-1 under simulated sunlight and near-infrared light irradiation, respectively, far exceeding other layered metal phospho-sulfides. This work offers a distinctive perspective for the development of new near-infrared-responsive photocatalysts.

Rapid synthesis of PdCu nanosheets with enhanced electrocatalytic activity toward polyalcohol oxidation reaction

Reasonable design of Pd-based catalysts with specific composition and morphology is of great importance for promoting the commercial application.of direct alcohol fuel cells (DAFCs). Recently, two-dimension (2D) with high density of defects and massive low-coordinated surface atom has become research highlights in the field of catalysis. Herein, we report a wet chemical method for synthesizing PdCu nanosheets with abundant wrinkles. The ultrathin two-dimensional structure endows catalysts plentiful catalytic active sites and large specific surface area, improving atomic utilization efficiency. The formation of bimetallic PdCu alloy structure leads to the adjustment of Pd electronic structure, resulting in lattice compression effect. Benefitting from the structural and compositional characteristics, PdCu nanosheets (NSs) exhibits excellent electrocatalytic performance for ethylene glycol oxidation reaction (EGOR) and glycerol oxidation reaction (GOR) with the mass activity of 7031 mA mg−1/5117 mA mg−1, which is 4.4/3.9 times higher than that of commercial Pd/C catalysts. Furthermore, the remained mass activity of PdCu NSs is 3991/3851 mA mg−1 after the durability measurement for EGOR/GOR, which confirm PdCu NSs possesses superior stability. We believe that our synthetic strategy could provide robust reference for the development of high-performance eletrocatalysts.

Ultrathin absorber with independently tunable dual-resonances for terahertz sensing

A technique is implemented for the generation and alteration of two independently tunable resonance peaks in a graphene based ultrathin absorber structure designed for the terahertz spectrum. The proposed structure is a multi-layered stacked arrangement of two resonator layers of graphene grown over the top of two isolated dielectric (SiO2) substrate layers shielded by a gold metal reflector at the bottom. The structure exhibits very low thickness profile and can be implemented with a thickness equivalent to λ/19.6 where λ is the free space wavelength. Two patterned graphene layers contributes to two independently tunable narrowband/near-perfect absorption peaks at 9.56 THz and 10.96 THz. This polarisation insensitive absorber structure also exhibits frequency ratio tunability of higher order mode with respect to lower order mode by distinctly/separately varying the Fermi level of graphene layers. The response is stable for a wider angle of wave incidence up to 70°. Its narrowband response makes it a suitable candidate to be utilized as biosensor for refractive index sensing.

Multihole Ce-doped NiSe2/CoP hybrid nanosheets for improved electrocatalytic alkaline water and simulative seawater oxidation

The investigation of cost-effective and highly efficient electrocatalysts for alkaline water and simulative seawater oxidation is essential to the conversion and storage of renewable energy. In this paper, the Ce–NiSe2/CoP catalyst with multihole and ultrathin nanosheet structure is generated. The unique structural characteristics of Ce–NiSe2/CoP heterojunction nanosheets contribute the excellent OER performance under different alkaline 1 M KOH and simulated seawater (1 M KOH + 0.5 M NaCl) electrolytes. Specifically, this catalyst exhucture is generated. The unique structural characteristics of Ce–NiSe2/CoP heterojunction nanosheets conibits the low overpotentials of 287 and 304 mV at the current density of 10 mA cm−2, along with the Tafel slopes of 87.1 and 78.8 mV dec−1 in two solutions, respectively. Moreover, the Ce–NiSe2/CoP target product also displays good stability. The present study introduces a promising strategy for the advancement of high-performance electrocatalysts in green energy field.

Construction of Ultrathin BiVO4‐Au‐Cu2O Nanosheets with Multiple Charge Transfer Paths for Effective Visible‐Light‐Driven Photocatalytic Degradation of Tetracycline

AbstractIn this study, unique BiVO4‐Au‐Cu2O nanosheets (NSs) are well designed and multiple charge transfer paths are consequently constructed. The X‐ray photoelectron spectroscopy measurement during a light off‐on‐off cycle and redox capability tests of the photo‐generated charge carriers confirmed the formation of Z‐scheme heterojunction, which can facilitate the charge carrier separation and transfer and maintain the original strong redox potentials of the respective component in the heterojunction. The ultrathin 2D structure of the BiVO4 NSs provided sufficient surface area for the photocatalytic reaction. The local surface plasmon resonance (LSPR) effect of the electron mediator, Au NPs, enhanced the light absorption and promoted the excitation of hot electrons. The multiple charge transfer paths effectively promoted the separation and transfer of the charge carrier. The synergism of the abovementioned properties endowed the BiVO4‐Au‐Cu2O NSs with satisfactory photocatalytic activity in the degradation of tetracycline (Tc) with a removal rate of ≈80% within 30 min under visible light irradiation. The degradation products during the photocatalysis are confirmed by using ultra‐high performance liquid chromatography‐mass spectrometry and the plausible degradation pathways of Tc are consequently proposed. This work paves a strategy for developing highly efficient visible‐light‐driven photocatalysts with multiple charge transfer paths for removing organic contaminants in water.

Photothermal catalysis enhances cellulose oxidation kinetics to promote the hydrogen evolution in alkaline solution over Pt/ZnIn2S4

The slow oxidation kinetics of cellulose severely limits photocatalytic cellulose reforming for hydrogen production. Herein, ZIS photocatalysts with different morphologies were prepared and Pt nanoparticles were deposited on their surfaces. The cellulose oxidation kinetics were enhanced through the strategy of photothermal catalysis and pH optimization, which led to efficient hydrogen generation. The ultrathin nanosheet structure endows 1 % Pt/ZIS-300 with a stronger photogenerated carrier separation ability than 1 % Pt/ZIS-0 (nanoflower) and facilitates ·OH generation. Heat can induce the production of ·OH from 1 % Pt/ZIS-300 and enhance the adsorption of 1 % Pt/ZIS-300 to cellulose by changing the surface potential of 1 % Pt/ZIS-300, which promotes the oxidation kinetics of cellulose. As a result, the hydrogen yield of 1 % Pt/ZIS-300 under photothermal catalytic condition (80 ℃) reached 1218 μmol/gcat after 4 h of reaction. Appropriate NaOH concentration contributes to cellulose solubilization and ·OH production, but too high OH− concentration causes a negative shift of the potential on the 1 % Pt/ZIS-300 and cellulose surface, which hinders the mass transfer process and reduces the oxidation kinetics of cellulose.

A Mini Review: Phase Regulation for Molybdenum Dichalcogenide Nanomaterials.

Atomically thin two-dimensional transition metal dichalcogenides (TMDCs) have been regarded as ideal and promising nanomaterials that bring broad application prospects in extensive fields due to their ultrathin layered structure, unique electronic band structure, and multiple spatial phase configurations. TMDCs with different phase structures exhibit great diversities in physical and chemical properties. By regulating the phase structure, their properties would be modified to broaden the application fields. In this mini review, focusing on the most widely concerned molybdenum dichalcogenides (MoX2: X = S, Se, Te), we summarized their phase structures and corresponding electronic properties. Particularly, the mechanisms of phase transformation are explained, and the common methods of phase regulation or phase stabilization strategies are systematically reviewed and discussed. We hope the review could provide guidance for the phase regulation of molybdenum dichalcogenides nanomaterials, and further promote their real industrial applications.

Ultrathin metal-organic framework nanosheets (Cu-TCPP) assembled micro flower combined with endonuclease signal amplification for ultrasensitive detection

Metal-organic framework play an important role in developing novel detection techniques. Herein, an ultrathin two-dimensional (2D) metal-organic framework nanosheet (Cu-TCPP) assembled microflower was successfully synthesized and applied for ultrasensitive detection. The high detection performance of Cu-TCPP microflower was attributed to high-capacity aptamer adsorption and specific desorption resulting from numerous approachable active sites, and its ultrathin nanosheets microflower-like structure. Moreover, the Cu-TCPP microflower had overcame the disadvantages of 2D MOF nanosheets which tended to agglomerate. Moreover, it exhibited excellent fluorescence quenching performance as a donor for fluorescence resonance energy transfer. Acetamiprid, a new chloronicotinic neurotoxic insecticide was used as the model analyte. The ultrasensitive sensor was developed by combining the Cu-TCPP microflower with deoxyribonuclease Ⅰ signal enhanced fluorescence. When acetamiprid was present, the fluorescent labeled aptamer probe was selectively bound to acetamiprid and desorbed from the Cu-TCPP microflower, resulting in fluorescence recovery. Subsequently, DNase Ⅰ was used to cleave the DNA strands of the aptamer probe, and acetamiprid was released to participate in a new cycle. The detection limit of the assay was as low as 5.56 pg/mL with a linear range 50.00 pg/mL∼5.00 μg/mL, and it was a universal platform to detect other analytes.

Cobalt phosphide embedded on interconnected ultrathin carbon nanosheets as an electrocatalyst for hydrogen evolution in alkaline medium

A highly effective hydrogen evolution reaction (HER) electrocatalyst was developed by combining Co2P nanoparticles (Co2P NPs) embedded on interconnected and ultrathin carbon nanosheets (CNS) through a facial in-situ thermal decomposition of the cobalt-triphenylphosphine complex. CNS were derived from the pyrolysis of sodium citrate in one step, resulting in an interconnected ultrathin nanosheet structure with a small thickness. The interaction between Co2P NPs and CNS boosted the electron transfer rate, resulting in a remarkable electrocatalytic performance toward the HER in an alkaline solution with excellent durability. An overpotential of −200 mV vs. RHE was sufficient to afford a current density of −10 mA cm−2 with a Tafel slope of 83.4 mV dec−1 in potassium hydroxide medium (1.0 M), which are lower than that of Co2P nanoparticles (-250 mV) with Tafel slope 93.3 mV dec−1. The electrochemical impedance spectroscopy data illustrated that the mutual coupling between the Co2P NPs and CNS supports the electrochemical HER performance and accelerates the kinetic of electron transfer. The high HER activity of the novel Co2P NPs/CNS catalyst is ascribed to the presence of CNS robust support.

Broadband metal-free graphite absorber for the shielding of far-infrared radiations

An ultrathin metal-free broadband absorber covering the far-infrared region is designed and implemented. A graphite resonator and reflector are used to provide the dual-resonance with merged spectrum. The graphite resonator is perturbed to improve the impedance bandwidth of the absorber at both the resonances. This helps in obtaining the wide and merged resonance to provide the wide absorption spectrum by maintaining the level of absorption more than 90%. The electromagnetic resonances taking place in the absorber structure are the reason behind the operation of the proposed absorber hence the circuit model analysis is carried out to validate its operation. Moreover, the shielding effectiveness of the absorber can vary from 40 to more than 150 dB proving its capability to be utilized in EM shielding, packaging and thermal storage applications in lower THz frequency band with ultrathin structure.

Ultrathin 2D Alloyed Cu−Ga−Zn−S Curved Nanobelts for Boosting Visible‐Light Photocatalytic Hydrogen Evolution

Abstract2D semiconductor nanomaterials have received significant attention as photocatalysts for solar‐to‐hydrogen conversion due to their robust light absorption capacity, large specific surface area, and superior electron transport characteristics. Nevertheless, it is challenging to develop 2D quaternary copper‐based sulfides (QCSs) with functional integration of conducive structural features for photocatalysis from multiple elements and intricate control conditions. Herein, ultrathin 2D alloyed Cu−Ga−Zn−S (CGZS) curved nanobelts (NBs) are fabricated by using a facile one‐pot colloidal method. Subsequently, the derived Cu31S16‐CGZS Janus heterostructures are designed by increasing Cu concentrations. The formation mechanism of 2D curved alloys and Janus heterostructures is systematically investigated. Without cocatalysts, curved alloyed CGZS NBs demonstrated superior photocatalytic activities of 1264.2 µmol g−1 h−1 compared to Janus heterostructured Cu31S16−CGZS (463.1 µmol g−1 h−1) under visible light (> 400 nm). Experimental and theoretical results unveiled that the improved photocatalytic activities of curved CGZS NBs can be attributed to enhanced charge–carrier separation efficiency resulting from high crystallinity and ultrathin 2D structure, abundant active sites from curved structure, high‐active (0001) crystal facet with the lowest reaction Gibbs energy, work function, and metal‐like properties. This work offers new insights into functional integration into ultrathin 2D QCSs with enhanced visible‐light photocatalytic performance.

Construction of carbon and nitride double vacancy defects on ultrathin porous g-C3N4 nanosheets assisted by freeze-drying for enhanced photocatalysis

Graphitic carbon nitride based photocatalysts have been found extensive application in the degradation of antibiotics and organic pollutants. However, the insufficient of surface active sites and the low efficiency of photogenerated charge carriers separation hinder the development. Herein, ultrathin porous polymer carbon nitride nanosheets (PCNS-F) with carbon and nitride double vacancy defects were successfully fabricated. The facile freeze-drying step, following solvent-thermal treatment and preceding the thermal etching process, stands as a critical step for triggering vacancy generation and adjusting the carbon/nitride ratio. The optimized PCNS-F photocatalyst exhibits an ultrathin structure featuring a substantial abundance of defects in a porous state, resulting in exceptional structural characteristics (183.3 m² g-1, 0.84 cm³ g-1). Surface defect sites increase, and the efficient separation and transfer of photo-generated charge carriers are promoted with the introduction of a suitable vacancy density. PCNS-F demonstrated outstanding photocatalytic degradation performances for tetracycline (81.7 %) and methylene blue (97.7 %) under visible light irradiation for 2 h, which are 10 and 7.2 times higher than those of bulk g-C3N4. The active species of ∙O2- was confirmed to play a major role in the photodegradation process. This work provides a mild approach for engineering carbon and nitride double vacancy defects on g-C3N4 nanosheets, accompanied by tuning carbon/nitride ratio, to effectively eliminate pollutants and cleanse the environment.’

Absorber layer improvement and performance analysis of CIGS thin-film solar cell

CIGS has shown significant potential for cost-effective and efficient photovoltaic applications, with efficiency often exceeding 20%. However, further improvements in cell performance are needed to reduce production costs. Thus, this study proposes an ultra-thin structure for CIGS solar cells by modifying the absorber layer thickness and composition. SCAPS software was used to evaluate the performance of the proposed design, such as open-circuit voltage (Voc), short-circuit current (Jsc), fill factor (FF%), and conversion efficiency (ŋ%). Results showed that ultra-thin solar cells with the proposed GnP and CGS absorber layers are ideal due to their greater ŋ%, 25.33%.

Ultrathin TiS2@N,S-Doped Carbon Hybrid Nanosheets as Highly Efficient Photoresponsive Antibacterial Agents.

Nanobactericides are employed as a promising class of nanomaterials for eradicating microbial infections, considering the rapid resistance risks of conventional antibiotics. Herein, we present a pioneering approach, reporting the synthesis of two-dimensional titanium disulfide nanosheets coated by nitrogen/sulfur-codoped carbon nanosheets (2D-TiS2@NSCLAA hybrid NSs) using a rapid l-ascorbic acid-assisted sulfurization of Ti3C2Tx-MXene to achieve efficient alternative bactericides. The as-developed materials were systematically characterized using a suite of different spectroscopy and microscopy techniques, in which the X-ray diffraction/Raman spectroscopy/X-ray photoelectron spectroscopy data confirm the existence of TiS2 and C, while the morphological investigation reveals single- to few-layered TiS2 NSs confined by N,S-doped C, suggesting the successful synthesis of the ultrathin hybrid NSs. From in vitro evaluation, the resultant product demonstrates impressive bactericidal potential against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli bacteria, achieving a substantial decrease in the bacterial viability under a 1.2 J dose of visible-light irradiation at the lowest concentration of 5 μg·mL-1 compared to Ti3C2Tx (15 μg·mL-1), TiS2-C (10 μg·mL-1), and standard antibiotic ciprofloxacin (15 μg·mL-1), respectively. The enhanced degradation efficiency is attributed to the ultrathin TiS2 NSs encapsulated within heteroatom N,S-doped C, facilitating effective photogenerated charge-carrier separation that generates multiple reactive oxygen species (ROS) and induced physical stress as well as piercing action due to its ultrathin structure, resulting in multimechanistic cytotoxicity and damage to bacterial cells. Furthermore, the obtained results from molecular docking studies conducted via computational simulation (in silico) of the as-synthesized materials against selected proteins (β-lactamasE.coli/DNA-GyrasE.coli) are well-consistent with the in vitro antibacterial results, providing strong and consistent validation. Thus, this sophisticated study presents a simple and effective synthesis technique for the structural engineering of metal sulfide-based hybrids as functionalized synthetic bactericides.

Crystalline-Amorphous Heterophase PdMoCrW Tetrametallene: Highly Efficient Oxygen Reduction Electrocatalysts for a Long-Term Zn-Air Battery.

Metallenes have received sustained attention owing to their unique microstructure characteristics and compelling catalytic applications, but the synthesis of multielement crystalline-amorphous metallenes remains a formidable challenge. Herein, we report a one-step wet chemical reduction method to synthesize composition-tunable crystalline-amorphous heterophase PdMoCrW tetrametallene. As-synthesized PdMoCrW tetrametallene is composed of approximately six to seven atomic layers and has flexible crimpiness, a crystalline-amorphous heterophase structure, and high-valence metal species. Time-dependent experiments show that PdMoCrW tetrametallene follows a three-step growth mechanism that includes nucleation, lateral growth, and atom diffusion, respectively. The novel ultrathin structure, optimized Pd electronic structure, and hydrophilic surface together greatly promote the activity and stability of PdMoCrW tetrametallene in the alkaline oxygen reduction reaction. Pd75.9Mo9.4Cr8.9W5.8/C exhibits excellent mass and specific activities of 2.81 A mgPd-1 and 4.05 mA cm-2, which are 20.07/14.46 and 23.42/16.20 times higher than those of commercial Pt/C and Pd/C, respectively. Furthermore, a Zn-air battery assembled using Pd75.9Mo9.4Cr8.9W5.8/C as a cathode catalyst achieves a peak power density of 156 mW cm-2 and an ultralong durability of 329 h. This study reports an effective strategy for constructing crystalline-amorphous quaternary metallenes to advance non-Pt electrocatalysts toward oxygen reduction reaction (ORR) performance and for a Zn-air battery.

Ultra-thin layer HTaMoO6 catalyst for the upgrading of carbohydrates into 5-hydroxymethylfurfural

The conversion of carbohydrates into 5-hydroxymethylfurfural (HMF), a vital and valuable platform chemical, is sought after in industrial applications but poses significant challenges. In this research, we engineered an ultra-thin layer HTaMoO6 catalyst using ball-milling/liquid-exfoliation technique, demonstrating its efficiency in catalyzing the transformation of carbohydrates to HMF. In contrast to the conventional method utilizing tetra(n-butylammonium) hydroxide as the intercalation agent, the ball-milling/liquid-exfoliation technique not only reduces catalyst preparation time (within 12 h) but also enhances the efficient intercalation, leading to the formation of an ultra-thin layer structure. The resulting catalyst exhibits high total acidity, a favorable Brønsted/Lewis acid ratio, and improved accessibility of active sites due to the thin layer structure post-exfoliation. Compared with bulk LiTaMoO6, the ultrathin layer HTaMoO6 catalyst enables complete fructose dehydration with an HMF yield reaching 89.1 % under moderate reaction conditions (120 °C, 1 h) and 47.2 % yield of HMF is obtained from sucrose at 130 °C. This work provides a new method to fabricate the solid acid for the transformation of carbohydrates.

Accelerated peroxidase-like activity of ultrathin amine-tagged bimetallic MOF-74 nanozyme for construction of versatile bioassays from small molecules to enzymes and bacteria

The exquisite design of nanostructures for enzyme-biocatalyzed active sites mimicking has become a prospective method to significantly boost biocatalytic properties, which is profitable to response amplification for bioanalysis scenarios. Metal-organic frameworks (MOFs) with customizable compositions, diverse microstructures and open catalytic sites are considered to deal with challenges in conventional materials of unfriendly microenvironment and inexact coordination. Herein, by combining a metal doping and post-synthetic modification approach, amine-tagged Fe-Ni bimetallic MOF-74 nanozyme (FeNi-MOF-74-NH2) with ultrathin structure and improved peroxidase-mimicking bioactivity is synthesized through a layered double hydroxide (LDH) directed method. The boosted biocatalytic property largely benefits from the synergistic effects of Fe-Ni species, attributing to the dual mechanism (electron transfer and generation of hydroxyl radicals). On the basis of the enhanced enzyme-mimicking property and accessible amino functionalization of FeNi-MOF-74-NH2, versatile applications were carried out for the ultrasensitive detection of analytes from bioactive small molecules (H2O2 and ascorbic acid), biomacromolecules (alkaline phosphatase, ascorbic acid oxidase, and α-glucosidase), and pathogenic bacteria (Staphylococcus aureus). The nanozyme-based biosensing platform without complex enzymatic techniques serves as a proof-of-concept to facilitate the application of MOF nanozymes in biochemical analysis, clinical diagnosis, and biomedical research.

P-doped ultrathin g-C3N4/In2S3 S-scheme heterojunction enhances photocatalytic hydrogen production and degradation of ofloxacin

In this work, ultrathin lamellar g-C3N4/In2S3 S-scheme heterojunctions doped with P were synthesized by urea recrystallization and investigated to see which ratio was more favorable for photocatalysis. The P doping formed a new Fermi energy level and reduced the forbidden bandwidth. The ultrathin lamellar structure facilitated rapid charge transfer, and the formation of S-scheme heterojunction, the presence of the interfacial electric field, and band bending effectively separated strong redox-capable electron-hole pairs, thus significantly improving the photocatalytic performance. Among the prepared materials, the 50UP-C3N4/In2S3 photocatalyst with 50 % UP-C3N4 mass fraction showed optimal photocatalytic H2 production performance, with a hydrogen production rate of 12,387 μmol h−1 g−1. Moreover, it showed good performance in photocatalytic degradation, with a degradation efficiency of up to 90.2 % of ofloxacin after 120 min of light exposure. This article provided a new perspective on the synthesis of other photocatalysts with carbazide-based S-scheme heterojunction structures.