Band Structure Calculations Research Articles

Novel superhard orthorhombic O12 carbon: a first principle study

Abstract In this study, a new orthorhombic carbon structure with Ama2 symmetry, designated as O12 carbon, has been predicted on basis of the first-principles method. The thermal stability and dynamic stability of O12 carbon were evaluated and confirmed by combining ab initio molecular dynamics and phonon spectra analyses. Meanwhile, the mechanical properties of O12 carbon, compared with other superhard carbon allostrope like diamond, M-carbon, Bct-c4 and Cco-C8, have also been systematically investigated. With a bulk modulus of 351 GPa, a shear modulus of 333 GPa, and a Vickers hardness of 53 GPa, O12 carbon is identified as a superhard material of significantly technological and industrial applications. The existence of elastic anisotropy in O12 carbon has also been confirmed. The electronic band structure calculations have revealed that O12 carbon exhibits a semiconductor characteristic with a direct band gap of 2.5 eV, making it promising candidate in electronic applications. Additionally, the XRD spectra of O12 carbon were obtained to offer further insights for potential experimental observations. Our findings enrich the family of carbon structure and are expected to stimulate additional experimental interest.

Ultra-broadband emission from Mg7Ga2GeO12:Ni2+,Cr3+ phosphor spanning the NIR I–III regions for spectroscopy applications

Ultra-broadband near-infrared (NIR) lighting sources covering NIR Ⅰ to III regions are pivotal components for NIR spectroscopy devices. However, achieving ultra-broadband and efficient emission covering the entire NIR Ⅰ to III regions remains a significant challenge. To address this, we selected Mg7Ga2GeO12 as host material to realize ultra-broadband NIR emission. Density functional theory calculations on formation energies confirmed the feasibility of doping both Ni2+ and Cr3+ within Mg7Ga2GeO12. Band structure calculations reveal a significantly reduced band gap upon the doping of Ni2+. Following that, we synthesized Mg7Ga2GeO12:Ni2+ through conventional solid-state-reaction method. This phosphor exhibits broadband NIR emission with a full-width-at-half-maximum of 377 nm in the range of NIR II ∼ III (1100–2100 nm). To further enhance the emission efficiency, we co-doped Mg7Ga2GeO12:Ni2+ phosphor with Cr3+. This co-doping strategy not only dramatically enhances the Ni2+ emission intensity, but also extends the lower limit of emission band to 600 nm. However, a spectral gap around 1150 nm remains between Cr3+ and Ni2+ emission centers. To bridge this spectral gap, we employed LiScSiO4:Cr3+ phosphor alongside Mg7Ga2GeO12:Ni2+,Cr3+ phosphor to fabricate a phosphor converted LED (pc-LED) with ultra-broadband NIR emission covering entire NIR Ⅰ to III regions. By utilizing this pc-LED as the lighting source for NIR spectral detection, multiple organic functional group signals can be identified simultaneously in NIR II and III bands from 1000 to 2100 nm. The performance of such an NIR pc-LED not only confirms the application potential of Mg7Ga2GeO12:Ni2+,Cr3+ phosphor in non-destructive spectral analysis but also underscores the feasibility of combining two phosphors to achieve ultra-broadband NIR pc-LEDs, rendering them suitable to be lighting sources for portable spectrometers.

MAX phase borides, the potential alternative of well-known MAX phase carbides: A case study of V2AB [A = Ge, P, Tl, Zn] via DFT method

This study predicted four new MAX phase borides via the DFT method, with a comprehensive and thorough approach. The stability of the predicted phases has been thoroughly studied using formation energy, phonon dispersion curve (PDC), and elastic constants (Cij). The metallic nature of the studied phases is confirmed through the computation of the electronic band structure and density of states (DOS). Their bonding nature is disclosed using the partial density of states, Mulliken population analysis, and charge density mapping. The mechanical behavior is investigated in depth by calculating elastic constants, elastic moduli, Poisson's & Pugh ratio, machinability index, and Vickers hardness. Different anisotropic indices are also computed to demonstrate the elastic anisotropy. The Debye temperature (ΘD), Grüneisen parameter (γ), phonon thermal conductivity (kph), minimum thermal conductivity (kmin), thermal expansion coefficient (TEC), and melting temperature (Tm) are all calculated, and the suitability of the studied phases as thermal barrier coating (TBC) materials has been discussed. Finally, the optical constants are calculated and analyzed, further certifying the metallic nature of the herein-studied phases. The reflectivity spectra of all the herein selected compounds reveal their potential as coating materials to lessen solar heating. Among the studied phases, V2PB exhibits the best thermo-mechanical properties for potential applications in diverse fields, such as structural components and TBC materials. The potential applications of our findings are vast, and the obtained results reveal that the predicted phases are indeed potential alternatives to their counterpart carbides.

Investigating the Optoelectronic Properties of 2‐D and 3‐D CaTi1−xCuxO3 as a Phosphor Materials: A Density Functional Theory Approach

ABSTRACTThe CaTiO3 has been extensively investigated as a highly promising optical material mostly for its optoelectronic properties and its function as a host for transition metals doped in the CaTiO3. Electronic and optical properties of CaTi1−xCuxO3 (2‐D and 3‐D) have been thoroughly analyzed using first‐principles calculations based on Density Functional Theory (DFT). The calculations of these properties in both 2‐D and 3‐D configurations have performed by the use of generalized gradient approximation plus Hubbard (GGA + U). The electronic characteristics including the electronic band structure, partial density of states, and total density of states have been meticulously computed for CaTi1−xCuxO3 in both 2‐D and 3‐D. Upon analyzing the obtained results, we investigated that conduction and valence bands overlapped for both 2‐D and 3‐D structures revealing the metallic nature. We observed transitions mainly attributed to Cu‐d, Ti‐d, Ti‐p, and O‐p orbitals in both 2‐D and 3‐D configurations. Discussion delves into the significance of electronic band structure calculations in understanding optical properties. Peaks in the energy loss function are observed at 13 eV in both cases referred to the plasmon energy. Static values of the dielectric functions, extinction coefficient, reflectivity, and refraction are also computed. Our obtained results showed that the CaTi1−xCuxO3 compound in 3‐D form is more apt for optoelectronic devices and UV‐LED applications.

Enhancement of the thermoelectric figure of merit in the dirac semimetal Cd3As2 by band-structure and -filling control

ABSTRACT Topological materials attract a considerable research interest because of their characteristic band structure giving rise to various new phenomena in quantum physics. Beside this, they are tempting from a functional materials point of view: Topological materials bear potential for an enhanced thermoelectric efficiency because they possess the required ingredients, such as intermediate carrier concentrations, large mobilities, heavy elements etc. Against this background, this work reports an enhanced thermoelectric performance of the topological Dirac semimetal Cd3As2 upon alloying the trivial semiconductor Zn3As2. This allows to gain fine-tuned control over both the band filling and the band topology in Cd3-x Zn x As2. As a result, the thermoelectric figure of merit exceeds 0.5 around x = 0.6 and x = 1.2 at elevated temperatures. The former is due to an enhancement of the power factor, while the latter is a consequence of a strong suppression of the thermal conductivity. In addition, in terms of first-principle band structure calculations, the thermopower in this system is theoretically evaluated, which suggests that the topological aspects of the band structure change when traversing x = 1.2 .

Fermi surface and Lifshitz transitions of a ferromagnetic superconductor under external magnetic fields

Lifshitz transitions are being increasingly recognized as significant in a wide variety of strongly correlated and topological materials, and understanding the origin and influence of Lifshitz transitions is leading to deeper understanding of key aspects of magnetic, transport, or quantum critical behavior. In the ferromagnetic superconductor UCoGe, a magnetic field applied along the c axis has been shown to induce a series of anomalies in both transport and thermopower that may be caused by Lifshitz transitions. The need to understand the subtleties of the relationship between magnetism, superconductivity and a heavy-electron Fermi surface in the ferromagnetic superconductors makes it important to explore if and why a series of magnetic-field-induced Lifshitz transitions occurs in UCoGe. Here we report magnetic susceptibility measurements of UCoGe, performed at temperatures down to 45 mK and magnetic fields (μ0H||c) up to 30 T. We observe a series of clearly defined features in the susceptibility, and multiple sets of strongly field-dependent de Haas-van Alphen oscillations, from which we extract detailed field dependence of the quasiparticle properties. We complement our experimental results with density functional theory band structure calculations, and include a simple model of the influence of magnetic field on the calculated Fermi surface. By comparing experimental and calculated results, we determine the likely shape of the Fermi surface and identify candidate Lifshitz transitions that could correspond to two of the features in susceptibility. We connect these results to the development of magnetization in the system. Published by the American Physical Society 2024

Ta4SBr11: A Cluster Mott Insulator with a Corrugated, Van der Waals Layered Structure.

The compound Ta4SBr11 was prepared by a comproportionation reaction of tantalum bromide with tantalum and elemental sulfur. The crystal structure, as refined by single-crystal X-ray diffraction, is composed of clusters with Ta4S cores, arranged in corrugated van der Waals layers. Individual layers appear to be displaced relative to each other along one direction. Successful crystal growth in a melt of CsBr yielded black platelets of Ta4SBr11, which were used to investigate the electrical properties of the compound. The electronic structure was studied by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and by density functional theory (DFT) band structure calculations, revealing this material to be a small-gap semiconductor. DFT results, in combination with magnetic susceptibility measurements, suggest that metallicity originating from the one unpaired Ta d electron per cluster is most likely suppressed by electronic correlations, forming a cluster Mott insulator.

Nanoheteroepitaxy of Ge and SiGe on Si: role of composition and capping on quantum dot photoluminescence.

We investigate the nanoheteroepitaxy of SiGe and Ge quantum dots (QDs) grown on nanotips substrates realized in Si(001) wafers. Due to the lattice strain compliance, enabled by the nanometric size of the tip and the limited dot/substrate interface area, which helps to reduce dot/substrate interdiffusion, the strain and SiGe composition in the QDs could be decoupled. This demonstrates a key advantage of the nanoheteroepitaxy over the Stranski-Krastanow growth mechanism. Nearly semi-spherical, defect-free, ∼100 nm wide SiGe QDs with different Ge contents were successfully grown on the nanotips with high selectivity and size uniformity. On the dots, thin dielectric capping layers were deposited, improving the optical properties by the passivation of surface states. Intense photoluminescence was measured from all samples investigated with emission energy, intensity, and spectral linewidth dependent on the SiGe composition of the QDs and the different capping layers. Radiative recombination occurs in the QDs, and its energy matches the results of band-structure calculations that consider strain compliance between the QD and the tip. The nanotips arrangement and the selective growth of QDs allow to studying the PL emission from only 3-4 QDs, demonstrating a bright emission and the possibility of selective addressing. These findings will support the design of optoelectronic devices based on CMOS-compatible emitters.

Signature of pressure-induced topological phase transition in ZrTe5

The layered van der Waals material ZrTe5 is known as a candidate topological insulator (TI), however its topological phase and the relation with other properties such as an apparent Dirac semimetallic state is still a subject of debate. We employ a semiclassical multicarrier transport (MCT) model to analyze the magnetotransport of ZrTe5 nanodevices at hydrostatic pressures up to 2 GPa. The temperature dependence of the MCT results between 10 and 300 K is assessed in the context of thermal activation, and we obtain the positions of conduction and valence band edges in the vicinity of the chemical potential. We find evidence of the closing and re-opening of the band gap with increasing pressure, which is consistent with a phase transition from weak to strong TI. This matches expectations from ab initio band structure calculations, as well as previous observations that CVT-grown ZrTe5 is a weak TI in ambient conditions.

Monolayer Penta-BeAs2: A Promising 2D Materials for Toxic Gas Sensor with High Selectivity.

The discovery of novel materials with high gas sensing selectivity is a key driver of gas sensor technology. Based on the recently reported two-dimensional (2D) pentagonal BeP2, we introduce penta-BeAs2 as a new member of the pentagonal family of materials for toxic gas sensors based on density functional theory (DFT). For electronic applications, a band structure calculation showed that penta-BeAs2 has indirect band gaps of 0.38 and 0.79 eV, using GGA-PBE or HSE functionals. Stability analysis confirmed that penta-BeAs2 is dynamically, mechanically, and thermally stable. The adsorption of toxic gases (CO, NO, and NO2) and nontoxic gases (H2, N2, H2O, and CO2) on the penta-BeAs2 monolayer was studied. The contrasting adsorption behavior observed between toxic and nontoxic gases on penta-BeAs2 (physisorption vs chemisorption) underscores its high selectivity for toxic gas-sensing applications. Adsorption energies for toxic gases fall within a moderate range (0.4-0.8 eV), indicating good reversibility and short recovery times at room temperature. Additionally, the quantum transport properties of penta-BeAs2 were studied using the nonequilibrium Green's function (NEGF) approach, confirming strong sensitivity and selectivity toward toxic gases.

Dual S-Scheme g-C3N4/Ag3PO4/g-C3N5 photocatalysts for removal of tetracycline pollutants through enhanced molecular oxygen activation

A dual S-scheme g-C3N4/Ag3PO4/g-C3N5 heterojunction was prepared by decomposition methods, and it displayed enhanced performance to degrade tetracycline hydrochloride with the ideal stability under different water substrates and ions. Comparing with three single components, as g-C3N4, g-C3N5, and Ag3PO4, the dual S-scheme g-C3N4/Ag3PO4/g-C3N5 heterojunction displayed 4.4-, 3.4-, and 2.5-times enhancements in the tetracycline hydrochloride removal. Based on the dynamics analyses for charge carriers and band structure calculations, two channels of molecular oxygen activation (MOA) between Ag3PO4 and g-C3N4 (and g-C3N5) were confirmed. More importantly, according to this double consumption process of excited electrons, dual S-scheme g-C3N4/Ag3PO4/g-C3N5 could suppress the charge recombination, which was the key point to boosting photocatalytic activity. Moreover, the determination of intermediates also supported the vital role of MOA during these photocatalytic reactions. this report of two reactive sites in MOA that generate reactive oxygen species in a “V” type band structure. The electronic dynamic in the reaction was also testified by several detections, indicating the enhanced charge separation and migration from internal field effect and electron trapping from dual S-scheme mechanism. This work provides a new research direction for the design and mechanism analysis of dual S-scheme photocatalysts

Dynamic Condensation for Efficient Band-Structure Calculations of 2D Periodic Structures

Efficient band-structure calculations are essential for understanding the mechanical behaviors of periodic materials, with significant implications in material design and phononic engineering. This paper introduces the application of the improved reduced system (IRS) technique to expedite elastic band-structure calculations. The IRS, a dynamic condensation method, partitions the unit cell degrees of freedom (DOFs) into primary and secondary sets. A strategic selection of primary DOFs retains a subset of interior DOFs alongside all exterior DOFs while truncating the remaining interior DOFs. The integration of IRS with the Craig–Bampton method for additional reduction and the imposition of Bloch boundary conditions yields a notable decrease in computational overhead. Additionally, for structures with a high number of interior DOFs, a substructuring scheme can be implemented to further enhance efficiency. This approach offers a compelling combination of accuracy and expedited computation, making it applicable across diverse periodic materials.

Evolution of ferromagnetism and electrical resistivity in Sb-doped Cr4PtGa17

We describe the doping effects on a metallic breathing pyrochlore compound, Cr4PtGa17. Upon doping with Sb, i.e., Cr4Pt(Ga1-xSbx)17, it was found that a selective doping on one of the seven Ga sites occurs. With increasing dopant level, the ferromagnetism in the parent compound is gradually suppressed, along with a decrease in fitted Curie-Weiss temperature (from 61 (1) K to −1.8 (1) K) and effective moment (from ∼2.26 μB/f.u. to ∼0.68 μB/f.u.). Low-temperature heat capacity measurements confirm the absence of magnetic ordering above 0.4 K for the three most doped samples. Meanwhile, electrical resistivity measurements display a metal-semiconductor transition with increasing Sb contents, which is attributed to an increase of Fermi energy based on the calculations of electronic band structure and density of states. Moreover, we have speculated that the ferromagnetism in Cr4PtGa17 is governed by itinerant electrons according to our observations. This study of Sb-doping effect on Cr4PtGa17 provides deeper understanding of magnetism of this system and possibilities for future modifications.

Atomic defects (vacancy, substitutional, and Stone-Wales) in monolayer aluminum nitride: a density-functional-theory simulation

Abstract Aluminum nitride (AlN) is a mechanically strong material with a high melting point and excellent thermal conductivity. In this study, the AlN is modeled with defects in vacancies, substitutions, and Stone-Wales using a density functional theory (DFT). We model six configurations, two configurations of monovacancies: aluminum vacancy (VAl) and vacancy nitrogen (VN), two configurations of substitutions: aluminum substitution (SN→Al) and nitrogen substitution (SAl→N), the interchange (IAl↔N), and Stone-Wales (S–W). We find structural changes in each defect with outward relaxation and VN with inward relaxation. the band structure calculations show that the geometric structure introduces new states near the Fermi level except for the VAl system.

Impact of Lattice Strain on the Electronic and Thermoelectric Properties of CoAs3 Skutterudite Material

Using density functional theory (DFT) combined with semi‐classical Boltzmann transport theory, the electronic and thermoelectric properties of binary skutterudite CoAs3 material are investigated up to 30 GPa. Elastic properties calculations confirm the mechanical stability at 0 GPa and under varying hydrostatic pressures, with ductility influenced by pressure. To ensure dynamical stability, the phonon dispersion frequencies are computed at both 0 and 30 GPa. Electronic band structure calculations, using the GGA + TB‐mBJ approximation, indicate that CoAs3 initially exhibits a direct band gap at its equilibrium lattice constant, which shifts to become indirect under increasing pressure. To assess the impact of pressure on the thermoelectric properties of CoAs3, the Seebeck coefficient, thermal conductivities, and figure of merit (ZT) are calculated at pressures of 5, 10, 20, and 30 GPa for various temperatures (300, 600, 900, and 1200 K). These computations provide valuable insights into how varying pressures influence the material's thermoelectric performance. The optimal thermoelectric properties in CoAs3 material are achieved at 5 GPa and 1200 K for n‐doping (20 GPa and 600 K for p‐doping), with an ideal doping concentration of 1.5 × 1021 cm−3 (5.5 × 1018 cm−3). Under these conditions, the material reaches a high figure of merit (ZT) value of 0.52 for n‐doping and 0.49 for p‐doping. These findings underscore CoAs3 as a promising candidate for applications in energy harvesting and optoelectronic systems, showcasing its robust thermoelectric performance under precise pressure and temperature conditions.

Appearance of topological phase in YAs semimetal under hydrostatic pressure and epitaxial strain

By means of hybrid density functional theory, we present the evolution of the topological phase in rare earth monopnictide YAs with hydrostatic pressure and epitaxial strain. This material exists in NaCl-type structure at ambient conditions and shows structural phase transition into CsCl-type structure at 56.54 GPa hydrostatic pressure. The epitaxial strain reduces the structure into a compressed tetragonal-type. The thermodynamical and dynamical stability of the material is established with the calculation of enthalpy and phonon band structure within structural phase transition, respectively. The topologically trivial phase of the material is observed at ambient pressure in agreement with previous reports. This material shows topological phase transition at 24.8 GPa applied hydrostatic pressure and 10% epitaxial strain. The band inversion at the X-point between d-Y and p-As orbitals is verified with the help of the product of parity analysis of all the filled bands. The presence of the Dirac cone in the (001) plane and the existence of topologically non-trivial states at M‾-point in the Fermi arc contour also established our claim. The Z2 indices are calculated with the help of the product of parities and a change in Z2 indices from (0; 000) to (1; 000) is also verified with the evolution of Wannier change centers under the conditions of applied hydrostatic pressure and epitaxial strain. The time reversal and inversion symmetries are preserved throughout the study and the topological phase transition at 24.8 GPa is much lower than the structural phase transition pressure i.e., 56.54 GPa.

Palladium based air-stable 2D penta-material’s heterostructures for water splitting applications

Heterostructures offer superior photocatalytic characteristics over their constituent counterparts due to their charge separation abilities. Here, we conduct a systematic study of a recently synthesized novel family of palladium-based pentagonal air-stable 2D monolayers, PdSe2, PdPSe, and PdPS, and their heterostructures using first-principles calculations for photocatalytic applications. Electronic band structure calculations reveal moderate bandgaps of 2.27 eV for PdSe2, 2.01 eV for PdPSe, and 2.25 eV for PdPS, indicating their suitability for photocatalytic water splitting. Moreover, to spatially separate and reduce the recombination possibility of photoinduced electron-hole pairs, we propose three van der Waals heterostructures: PdPSe/PdSe2, PdPS/PdSe2, PdPS/PdPS, with the corresponding bandgaps of 1.84 eV, 1.64 eV, and 1.65 eV, respectively. Based on work functions and the staggered band alignment of constituting monolayers, all three heterostructures are identified as type-II photocatalysts, which makes them notable photocatalyst. Additionally, band-edge potentials of PdPSe/PdSe2 and PdPS/PdSe2 confirm their suitability for overall water splitting via photocatalysis, whereas PdPS/PdPSe is suitable for oxygen evolution reactions only. The optical absorption spectra show the ability of each system to operate under a wide range of the spectrum, from visible light to high-energy (UV) regions. These characteristics make these systems valuable and attractive for photocatalytic applications.

Mechanical and optical properties of MgTa2O6 compounds: First principles study

In this study, we have explored the electronic, optical, and mechanical properties of MgTa2O6 compounds in both tetragonal and orthorhombic phases using the first principles based on density functional theory (DFT) methods. Considering that GGA underestimates the band gap of materials, the HSE06 hybrid functional is performed to get a more accurate result for the band structure and optical property calculations. The calculations indicate that the tetragonal and orthorhombic phases exhibit different optical characteristics, showcasing their potential as exceptional materials for UV absorption. In addition, we have thoroughly investigated the elastic properties of MgTa2O6 for these two phases, including the bulk modulus, shear modulus, Young's modulus, and Poisson's ratio. The results indicate that the tetragonal phase has better volume deformation and shear deformation resistance, and the surface contours of Young's modulus for MgTa2O6 display anisotropy. And according to Pugh's criteria, the tetragonal phase has good ductile properties.

Rational composition engineering toward high thermoelectric performance in p-type EuMg2Sb2-based materials

Mg-based compounds are emerging materials for efficient thermoelectric conversion, as exemplified by n-type Mg3Sb2-based materials, while a high performing p-type Mg3Sb2 material is lacking. EuMg2Sb2, a derivative of Mg3Sb2, has revealed potential as a high-performance alternative to p-type Mg3Sb2-based materials, while pristine EuMg2Sb2 suffers from low carrier concentration. Herein, we reveal that both Zn substitution for Mg and Yb substitution for Eu not only boost the carrier concentration and mobility of p-type EuMg2Sb2-based materials, but also sharply diminish the lattice thermal conductivity via enhancing phonon scattering. Band structure calculation shows that Zn substitution minimizes the energy difference between different bands at the valence band maximum and reduces the band effective mass, leading to optimized band structure. Combined with the role of Ag doping in increasing the carrier concentration and power factor, p-type Eu0.5Yb0.5Mg1.0975Zn0.9975Ag0.005Sb2 sample obtains a maximal dimensionless figure of merit (zT) value of 1.18 at 823 K, which compares favorably to those of EuMg2Sb2 and other p-type Mg–Sb-based Zintl materials. This study demonstrates the efficacy and importance of delicate composition engineering in boosting the thermoelectric performance of p-type EuMg2Sb2.

Synergistic interaction of S-type heterojunction and sulfur vacancies in g-C3N5@Sv-ZnIn2S4 composites: Simultaneous promotion of complete 2,4-dichlorophenol mineralization and Cr(VI) reduction

Constructing efficient heterojunction photocatalysts is an effective measure for degrading pesticides and reducing heavy metals. In this study, g-C3N5@Sv-ZnIn2S4 (g-C3N5@Sv-ZIS) composite with large specific surface area has been successfully prepared by a simple low-temperature water bath method. The g-C3N5@Sv-ZIS composite showed complete mineralization of 2,4-dichlorophenol (2,4-DCP) and reduction of Cr(VI) within 60 min. The results of electron spin resonance spectroscopy, photoelectrochemical characterization, and energy band structure calculations indicated the formation of an S-type heterojunction at the interface of g-C3N5 and Sv-ZIS. In situ XPS analysis showed the transfer of photogenerated charges from g-C3N5 to Sv-ZIS. The molecular structure of 2,4-DCP was analyzed using frontier molecular orbital and electrostatic potential calculations. The possible degradation pathways of 2,4-DCP were proposed based on liquid chromatography– mass spectrometry results. Biotoxicity simulations of the intermediates revealed decreased toxicities. Furthermore, The kinetic rate constant of CZSv-200 for degrading 2,4-DCP and Cr(Ⅵ) in deionized water was approximately 2.20, 3.10 and 2.46, 4.03 times higher than that in lake and sewage plant water, respectively. The composites designed in this study provide reliable theoretical support for the removal of composite pollutants.