Magneto-optical material is a kind of optical functional material which has the magneto-optical effect from ultraviolet to infrared band. According to the type of material, magneto-optical materials can be classified into magneto-optical glass, magneto-optical crystals, magneto-optical transparent ceramics, etc. As a new type of magneto- optical material which has emerged in recent years, magneto-optical transparent ceramics are considered as one of the most promising candidates for Faraday isolators used in high power lasers due to its high Verdet constant, large size, high thermal conductivity, and high laser-induced-damage threshold. Up to now, the magneto-optical transparent ceramics reported mainly include terbium gallium garnet (Tb₃Ga₅O₁₂, TGG), terbium aluminum garnet (Tb₃Al₅O₁₂, TAG) and some sesquioxide ceramics such as terbium oxide (Tb₂O₃), holmium oxide (Ho₂O₃), dysprosium oxide (Dy₂O₃), etc. In this paper, several common magneto-optical effects were briefly introduced, and the basic principles of Faraday effect and Kerr effect were illustrated in detail. In addition, the research progress, all-sides properties and application prospects of magneto-optical transparent ceramics were mainly reviewed. The properties of different kinds of magneto-optical transparent ceramics were compared and analyzed, and the existing problems as well as the research prospects were also proposed.

With the development of nuclear energy, the long-lived radionuclides are inevitably released into the natural environment during the mine process, fuel manufacture, nuclear power usable and spent fuel management, which are dangerous to human health and environmental pollution. Thereby the efficient elimination of radionuclides is an important parameter which affects the development of nuclear power. In recent years, the metal-organic frameworks (MOFs) have attracted worldwide attention in the adsorption of radionuclides from large volume of aqueous solutions, because of their high chemical stability, abundant functional groups and changeable porous structures. In this review, we mainly summarized the recent works of MOFs in the efficient removal of radionuclides, and to understand the interaction mechanism from batch adsorption experiments, model analysis, advanced spectroscopy analysis, and theoretical calculation. The adsorption capacities of MOFs with other materials were also summarized, and the future research opportunities and challenges are given in the perspective.

Using Ti₃AlC₂ as the precursor, a new MAX phase Ti₃ZnC₂ was synthesized via an A-elemental substitution reaction in a molten salts bath. Composition and crystal structure of Ti₃ZnC₂ were confirmed by XRD, SEM and TEM analysis. Its structure stability and lattice parameter of Ti₃ZnC₂ were further proved by a theoretical calculation based on density function theory (DFT). Moreover, thermodynamics of A-elemental substitution reactions based on Fe, Co, Ni, and Cu were investigated. All results indicated that the similar substitution reactions are feasible to form series of MAX phases whose A sites are Fe, Co, Ni, and Cu elements. The substitution reaction was achieved by diffusion of Zn atoms into A-layers of Ti₃AlC₂, which requires Al-Zn eutectic formation at high temperatures. The molten salts provided a moderate environment for substitution reaction and accelerated reaction dynamics. The major advantage of this substitution reaction is that MAX phase keeps individual metal carbide layers intact, thus the formation of competitive phases, such as MA alloys, was avoided. The proposed A-elemental substitution reactions approach opens a new door to design and synthesize novel MAX phases which could not be synthesized by the traditional methods.

Given the good electrochemical performance and excellent irradiation stability of two dimensional transition metal carbides (MXenes), the development of MXene-based electrode materials for radionuclide detection is very promising. In this work, Ti₃C₂T_x MXene was activated via an alkalization strategy to form K⁺ intercalated Ti₃C₂T_x (K-Ti₃C₂T_x). Then the modified electrode of K-Ti₃C₂T_x/GCE was prepared on glassy carbon electrode (GCE). Ti₃C₂T_x and K-Ti₃C₂T_x were characterized by XRD, SEM and XPS techniques, and the electrochemical detection performance of K-Ti₃C₂T_x/GCE for trace uranyl ion (UO₂²⁺) was further investigated. Cyclic voltammetry (CV) experiments showed that the electrochemical response of K-Ti₃C₂T_x/GCE modified electrode to UO₂²⁺ increased significantly. Under the differential pulse voltammetry (DPV) scanning at pH 4.0, the K-Ti₃C₂T_x/GCE modified electrode presented a good linear detection relationship for UO₂²⁺ in the uranium concentration range of 0.5-10mg/L. The detection limit of this method is 0.083 mg/L (S/N = 3), with decent stability and repeatability.

Thermoelectric (TE) power generation technology is highly expected for various applications such as special power supply, green energy, energy harvesting from the environment and harvesting of industrial waste heat. Over the past years, the record of zT values of TE materials has been continuously updated, which would bode well for widespread practical applications of TE technology. However, the TE device as the core technology for the TE application lags behind the development of TE materials. Especially, the large-scale application of TE power generation technology is facing bottlenecks and new challenges. This reviewpresents an overview of the recent progress on TE device design and integration with particular attentions on device optimization design, electrode fabrication, interface engineering, and service behavior. The future challenges and development strategies for large-scale application ofthermoelectric power generation are also discussed.

With rapid development of sustainable energies and energy conversion technologies, application prospect of thermoelectric (TE) materials in power generation and cooling has received increasing attention. The requirement of improving TE materials with high figure of merit becomes much more important. How to obtain the low lattice thermal conductivity is one of the main concerns in TE materials. In this review, the influences of specific heat, phonon group velocity and relaxation time on the lattice thermal conductivity are discussed, respectively. Several typical features of TE materials with intrinsic low lattice thermal conductivity are introduced, such as strong anharmonicity, weak chemical bonds and complex primitive cells. Introducing multiscale phonon scatterings to reduce the lattice thermal conductivity of known TE materials is also presented and discussed, including but not limited to point defect scattering, dislocation scattering, boundary scattering, resonance scattering and electron-phonon scattering. In addition, some theoretical models of the minimum lattice thermal conductivity are analyzed, which has certain theoretical significance for rapid screening of TE materials with low lattice thermal conductivity. Finally, the efficient ways to obtain the low lattice thermal conductivity for TE property optimization are proposed.

Photocatalyst of N-doped Bi₂O₂CO₃ (N-BOC)/CdSe quantun dots (QDs) composite was sucessfully prepared for degradation of nitric oxide (NO), an indoor air pollutant. The results of X-ray diffraction, transmisssion electron microscopy and X-ray photoelectron spectroscopy showed that after combination with CdSe QDs structure and morphology of N-BOC remained the same as before combination. Photocatalytic degradation of NO showed that introduction of CdSe QDs significantly enhanced the removal ratio of NO. Moreover, the generating ratio of toxic byproduct NO₂ decreased to 1%, which indicated efficient inhibition for the toxic byproduct generation. From UV-Vis absorption spectroscopy and photoluminescence spectroscopy, the CdSe QDs showed promotion on light absorption, and inhibition of charged recombination of photo-induced carriers. More importantly, only signals of NO₃ ^- were captured in in situ DRIFTS measurements, whilst the signals from NO₂ could be barely detected during photocatalytic process. Superoxide radicals (O₂ ^-) and holes (h ⁺) are considered to be possible active species in the reaction, which dominate the oxidation process from NO to NO₃ ^-.

3D printed bioceramics derived from preceramic polymers are of great interest in bone tissue engineering due to their simplified fabrication processes. In this study, three-dimensional (3D) porous β-Ca₂SiO₄ scaffolds incorporated with ZrO₂ were fabricated from silicone resin loaded with active CaCO₃ and inert ZrO₂ fillers by 3D printing. The fabricated scaffolds possessed uniform interconnected macropores with a high porosity (> 67%). The results showed that the increase of ZrO₂ incorporation significantly enhanced the compressive strength, and stimulated cell proliferation and differentiation of osteoblasts. Importantly, the in vivo results indicated that the ZrO₂-incorporated β-Ca₂SiO₄ scaffolds improved osteogenic capacity compared to pure β-Ca₂SiO₄ scaffolds. Taken together, the ZrO₂-incorporated β-Ca₂SiO₄ scaffolds fabricated by combining polymer-derived strategy with 3D printing could be a promising candidate for bone tissue engineering.

As for ceramic stereolithography technique, the preparation of suitable resin-based ceramic slurry is of primary importance. In this study, the effects of powder characteristics such as specific surface area, particle size and distribution, particle morphology on the rheological behavior of zirconia resin-based suspensions were investigated intensively. Results show that the specific surface area of the powder is the most important factor affecting slurry viscosity. Choosing low specific surface area and quasi-spherical shaped powder is more likely to obtain low viscosity slurries. In addition, the influence of solid loading on the flow behavior were also studied using Krieger-Dougherty model. Zirconia samples with the relative density of (97.83±0.33)% were obtained after sintering at 1550 ℃. No obvious abnormal grain growth in the microstructure of the sintered body is observed. Results indicate that after the optimization of the processing parameters with the help of rheology characterization, complex-shaped high-quality zirconia parts can be obtained using the stereolithography technique.

The quercus variabilis cork made up of cavity cells is used as raw material. Herein, the cork-derived activated carbon with the various pores was successfully prepared by the facile carbonization of cork followed by chemical activation. The as-prepared activated carbon sheets possess large specific surface area (2312 m ²/g) and unique interconnected pores. As a result, it shows excellent electrochemical performance as electrode material for supercapacitors. In three electrode system of KOH, it exhibits a high specific capacitance of 296 F/g at a current density of 0.1 A/g. The assembled symmetric supercapacitor shows a high specific capacitance of 201 F/g at 5 A/g, with a good cycling stability of 99.5 % capacitance retention after 5000 cycles. In two electrode system of Na₂SO₄, the symmetric supercapacitor displays a good rate performance of 80.5% retention from 0.5 A/g (174 F/g) to 50 A/g (140 F/g) and a high energy density of 19.62 Wh/kg.

The nitrogen-doped porous carbon applied for oxygen reduction reaction (ORR) has aroused extensive interests due to its unique physical and chemical properties. However, the complicated nitrogen-doping strategy and high cost limit its extensive application. In this work, a series of nitrogen-doped porous carbons were prepared by a facile pyrolysis process coupling with subsequent KOH activation using renewable N-enriched biomass potato as carbon source. Effects of activation temperature and KOH amounts on the textural properties and electrocatalytic ORR activities of the final samples were investigated in detail. The KOH activation treatment results in a high specific surface area (SSA) and hierarchical porous structure, which is beneficial for improved ORR performance. The optimized NPC-750 possesses a high SSA of 1134.2 m ²?g ^-1, developed hierarchical pores as well as moderate nitrogen content (1.57at%). It also exhibits a positive onset potential of 0.89 V (vs. RHE) and half-wave potential of 0.79 V (vs. RHE). Simultaneously, the advanced long-time stability and methanol-tolerance capacity were also obtained, implying that these biomass-derived porous carbons are potential low-cost ORR electrocatalysts. Moreover, these porous carbons show great potential in various fields including supercapacitors, adsorption/separation, catalysis and batteries as well.

Heterojunction-type nanostructures based on ZnO nanomaterials are one of the important candidates for constructing high-performance ultraviolet (UV) photodetectors. In this work, a novel ZnO nanorods/ZnCo₂O₄ nanoplates heterojunction was designed and prepared, and the electrical properties and photodetection properties of the as-prepared heterojunction were investigated. ZnCo₂O₄ nanoplates were constructed into uniform thin film on ITO glass substrate using oil/water interface self-assembly. Next, ZnO nanorod arrays with uniform orientation and proper density were grown on ZnCo₂O₄ nanoplates thin film using hydrothermal method with the help from ZnO seed layer. As a result, high-quality ZnO nanorods/ZnCo₂O₄ nanoplates heterojunction was achieved. This heterojunction has a high rectification ratio of 673.7. Under reverse bias, this heterojunction has a light-dark current ration of more than two orders of magnitude. The UV-visible rejection ratio of this heterojunction is 29.4, which indicates its selective detection of UV light. These results effectively prove the potential of this ZnO nanorods/ZnCo₂O₄ nanoplates heterojunction in constructing high-performance UV photodetectors.

In order to rapidly remove Eu(III) from aqueous solution, an alkalized two-dimensional titanium carbide, Na-Ti₃C₂T_x, was successfully prepared by treating inorganic two-dimensional transition metal carbide (MXene) with NaOH. Adsorption behavior of Eu(III) on Na-Ti₃C₂T_x was systematically investigated by batch experiments. The results show that the adsorption process is greatly affected by pH and ionic strength of the solution, and reached equilibrium within 5 min. Based on Langmuir model fitting results, the maximum adsorption capacity of Eu(III) on Na-Ti₃C₂T_x was calculated to be 54.05 mg/g at pH 4.0 under 298 K. The thermodynamic results suggested that the adsorption process was a spontaneous and endothermic reaction. The adsorption mechanism was further analyzed by energy dispersive X-ray spectroscopy (EDS), powder X-ray diffraction (XRD) and extended X-ray absorption fine structure spectroscopy (EXAFS). These data revealed that Na ⁺ ions inside MXene galleries were exchanged by Eu ³⁺ ions and Eu(III) existed dominately in under outer-sphere surface complexation after adsorption under acidic pH conditions, but in inner-sphere surface complexation under near-neutral pH conditions. Due to its cost-effective prepatation and excellent sorption performance, Na-Ti₃C₂T_x may be a promising candidate for the efficient removal of trivalent minor actinides and lanthanides from radioactive wastewater.

Terbium gallium garnet (TGG) ceramics were successfully fabricated by air sintering at 1500 ℃ for 3 h combined with HIP post-treating at 1550 ℃ for 3 h under 150 MPa argon gas, where the TGG powders were synthesized by the co-precipitation method employing ammonium hydrogen carbonate (AHC) as precipitant. The influences of ammonium hydrogen carbonate to metal ions molar ratio (R value) on phase composition and morphology of the resultant powders as well as optical transmittance and Verdet constant of the TGG ceramics were investigated systematically. The precursors with R=3.6, 4.0 and 4.4 calcined at 1100 ℃ form pure TGG phase, whereas the precursor with R=3.2 treated at the same temperature yields the mixed phases of TGG and Ga₂O₃. The TGG powder with R=4.0 shows the best dispersity and homogeneity, giving rise to ceramic with the best optical quality. On the contrary, the powder with R=4.4 exhibits a strong agglomeration, which is closely related to the morphology of its precursor. High quality TGG transparent ceramics with the transmittance of 80.1% at 1064 nm can be fabricated by the nanopowder with R=4.0, and the Verdet constant of the TGG ceramics at 633 nm is rather close to that of the commercial TGG single crystals (-134 rad·T ^-1·m ^-1).

Transparent ytterbium doped calcium fluoride ceramics (Yb:CaF₂) were successfully fabricated by vacuum sintering and hot pressing post-treatment from coprecipitated powders. In-line transmittance of 5at% Yb:CaF₂ transparent ceramics fabricated by pre-sintering at 600 ℃ for 1 h and hot pressing post-treatment at 700 ℃ for 2 h, reaches 92.0% at the wavelength of 1200 nm. Microstructure, spectroscopic characteristics and laser performance of the ceramics were measured and discussed. The sample shows a homogeneous microstructure with average grain size of 360 nm. Furthermore, the absorption cross section at 977 nm and the emission cross section at the 1030 nm of the ceramics are calculated to 0.39×10 ^-20 cm ²and 0.26×10 ^-20 cm ², respectively. Finally, the laser behavior was tested, finding a maximum output power of 0.9 W while the highest slope efficiency was 23.6%.

With the development of nuclear power, radioactive pollutants discharge into the environment and then contaminate soil and water resources. Nanoscale zero-valent iron (nZVI) materials are widely used in water remediation due to their strong reducibility and high removal efficiency. A carbon-based zero-valent iron material (Fe-CB) was prepared in this work. Fe-CB was fabricated using sodium alginate (SA) as a carbon source via one-step carbothermic method and then applied to eliminate U(Ⅵ) from aqueous solution. Its mechanism and adsorption properties of Fe-CB and U(VI) were studied by spectroscopic analyses and macroscopic experiments. The results illustrated that Fe-CB possessed of ample functional groups (such as -OH and -COOH) and high BET surface area, which made up for the dispersibility and low removal efficiency of nanoscale zero-valent iron (nZVI). The removal of U(VI) by Fe-CB achieved equilibrium in 3 h and the maximum sorption capacity was 77.3 mg·g ^-1 at 298 K. XPS analyses indicated that the U(Ⅵ) removal by Fe-CB was a synergistic effect of reductive adsorptive processes. Adsorption process resulted from surface complexation and the reduction process was dominated by U(VI) reduction to U(IV) by nZVI. The results show that Fe-CB can be used as an inexpensive and highly efficient pollutant scavenger, which has great potential for environment pollution management.

Mo₂Ga₂C, a double-A-layer MAX, is reported to be films or powders. This paper researched the sintering properties of M₂Ga₂C powders to make dense bulk samples by vacuum hot pressing. It was found that 750 ℃ was a suitable sintering temperature, while higher temperature (850 ℃) resulted in decomposition of Mo₂Ga₂C yielding to main product of Mo₂C. During sintering process at 750 ℃, its grain size did not increase obviously with sintering time, meanwhile the size of pores decreased markedly and the relative density increased significantly with the increasing sintering time. Additionally, the hot-pressed samples had obvious texture. Due to layering, some grains changed their orientations during sintering, of which most of the (00l) planes in the hot-pressed samples preferred to be perpendicular to the direction of hot press. Almost fully densed Mo₂Ga₂C bulk (relative density: 98.8%) was obtained by hot pressing at 750 ℃ for 8 h. This advantage of the method suggested that it can serve as a promising preparation for Mo₂Ga₂C, a double-A-Layer MAX.

Graphitic-like carbon nitride (g-C₃N₄), one of the most significant two-dimensional layered materials, has attracted worldwide attention in multidisciplinary areas such as photocatalysis, energy conversion and environmental pollution management. Its derivative compounds have also attracted multifarious attention owing to the intrinsic characters of their stable physicochemical properties, low cost and environmentally friendly features. This review focus on the design of high-performance g-C₃N₄-based nanomaterials and their potential for pollutant elimination in environmental pollution cleanup. Over the past few years, signi?cant advances have been achieved to synthesize g-C₃N₄ and g-C₃N₄-based nanomaterials, and their properties have been enhanced and characterized in detail. In this review, recent developments in the synthesis and modification of g-C₃N₄-based nanomaterials are summarized. The applications in heavy metal ions adsorption from wastewaters are gathered and their underlying reaction mechanisms are discussed. Finally, a summary and outlook are also briefly illustrated.

Photocatalysis technology possesses great potential in the field of oxidation of nitrogen oxides due to the low energy costs and little secondary pollution. Bismuth carbonate (Bi₂O₂CO₃, BOC)/polypyrrole (PPy) was prepared at room temperature to remove NO under visible light irradiation. After being decorated with PPy, the NO removal efficiency of BOC is enhanced from 9.4% to 20.4% while the generation of NO₂ is reduced from 2% to approximately zero, which are attributed to the oxygen vacancy formed at the interface between BOC and PPy via interfacial hydrogen bonding. Photocurrent and electrochemical impedance spectra indicate that oxygen vacancies promote the separation and migration of photo-induced electrons and holes over BOC, hence improve its photocatalytic activity. Furthermore, the presence of oxygen vacancy promotes the formation of more •O₂ ^-, and then improve the NO oxidation activity and safety of BOC together with •OH.

High-entropy ceramics, a novel class of single-phase ceramic solid solutions consisting of near-equimolar multielement species, are recently attracting tremendous attentions. Especially, the transition metal non-oxide high-entropy ceramics, such as transition metal carbide and boride high-entropy ceramics, have been proposed for potential applications in aerospace, nuclear energy, high-speed machining and many other extreme environments, owing to their excellent physical and chemical properties including super-high hardness, low thermal conductivity, good oxidation resistance and corrosion/erosion resistance. Recently, the research of high-entropy ceramics is only focused on composition design, fabrication methods, single-phase stability and mechanical properties, but the design criterion and theoretical analysis are rarely reported. Based on the researches of high-entropy alloy, the fabrication, characterization and theoretical study of several transition metal non-oxide high-entropy ceramics are summarized, along with some related results of high-entropy film. The prospects for the future developments of high-entropy ceramics are also discussed.

In recent years, ternary layered carbide/nitride MAX phases and their derived two-dimensional nanolaminates MXenes have attracted extensive attention. The crystal structure of MAX phase is composed of M_n+1X_n unit interleaved with layers of A element. MAX phases combine good properties of metal and ceramic, which makes them promising candidates for high temperature structural materials, friction and wear devices, nuclear structural materials, etc. When etching the A-layer atoms of the MAX phase, the two-dimensional nanolaminates with the composition of M_n+1X_nT_x (T_x is surface termination), i.e. MXene, is obtained. MXenes have wide range of composition, and tunable physical and chemical properties, which endow them great potential in the applications of energy storage devices, electromagnetic shielding materials, and electronic devices, etc. In this paper, the research progress of MAX phase and MXene was introduced in terms of composition and structure, synthesis methods, and properties and application. Furthermore, the research prospects of this large family of materials were discussed.

With the fast advancement of human modernization and rapid development of social economy, traditional energy consumption has been enormously increased and climate change has therefore become a very challenging issue for the human being. The development of modern industry, especially the chemical industry, has brought not only convenience to people, but also unprecedented destruction to the ecological environment closely related to human life. Energy and environmental issues have become a global challenge for us today. In order to better deal with the challenges and protect our living homeland, the majority of researchers are constantly seeking and exploring new materials and technologies which are environmentally friendly and can be used efficiently, aiming to solve increasingly serious environmental problems. In current stage, environmental materials and technologies have received ever-increasing attention and are developing rapidly.

Environmental materials, as the name implies, are materials designed and developed for environmental issues. The key issue of environmental problems is environmental pollution. At present, the widely concerned pollutants include gas pollutants, persistent organic pollutants (POPs), and heavy metals. At the same time, with drastic development of nuclear energy industry in the past two decades in China, radioactive pollutants have also received increasing attention. Separation and removal of these pollutants from environment by certain means is an effective and common method for environmental pollution control. Therefore, the key for solving environmental problems is to develop materials and technologies that can effectively remove environmental pollutants. Plenty of versatile materials for specific contaminant removals have been reported over the past few decades. These materials come in a wide variety of functions, with varying structures and performance. Most concerned materials include traditional molecular sieves^[1], mineral materials^[2], carbon materials such as graphene and carbon nanotubes^[3], polymer based materials such as resins^[4], metal organic frameworks (MOFs)^[5] and covalent organic frameworks (COFs)^[6]. Among these materials, inorganic materials have broad application prospects in the removal and separation of environmental pollutants due to their stability, low cost and environmental friendliness. In particular, inorganic nanoporous materials have become favorable in recent years. The nanometer size makes nanomaterials not only have quantum size effect, but also possess larger specific surface area and more surface atoms compared to other common materials, thus exhibiting stronger adsorption ability and better dispersibility in aqueous solution. In addition, the porosity of materials greatly enhances the specific surface area and correspondingly increases the contact opportunity between the material and contaminant. Meanwhile, it also improves the diffusion and transportation of contaminants inside the material, elevating the adsorption kinetics. Metal nanomaterials, metal oxide nanomaterials, mineral materials, etc. are typical representatives of inorganic nanomaterial family.

Based on the published works, many efforts in the field of inorganic environmental materials focused on improving the removal efficiency and selectivity toward one or more target pollutants. Inorganic materials have higher stability than organic materials, but possess low removal capacity and poor selectivity, due to lacking of active functional groups on the surface. Functionalization of inorganic materials should be a reasonable approach to overcome this drawback. It is well known that functional groups with strong binding or coordination ability to the target contaminant decorated on the surface of material by physical or chemical means can greatly improve the adsorption performance of inorganic materials^[7]. Moreover, besides modifying the specific recognition group on the surface of the material^[8], adjusting the pore structure of material and physically screening contaminants by the size effect^[9] are always common and effective. It is also promising to combine size effects, bonding and electrostatic interactions by means of molecular imprinting or composition^[10]. Besides, developing inorganic environmental materials used under harsh conditions^[11], such as high acid, high alkali, and high temperature, is becoming a research hot topic in recent years.

In all, after decades of development, researches on inorganic environmental materials have made significant progress, whereas most of materials are still not satisfactory for industrial applications. In order to better solve the increasingly serious environmental problems, it is still necessary for the material researchers to overcome difficulties and make continuous efforts.

Silicon carbide is widely used because of its excellent physical and chemical properties. The chemical bonding characteristics of SiC make it difficult to be sintered. Therefore, preparation of high-quality SiC ceramics is one of the challenges in SiC research field. In this study, the ternary rare-earth carbide Dy₃Si₂C₂ was proposed as a new sintering additive for SiC ceramics, through the phase transition of Dy-Si-C system at high temperatures to promote the densification of SiC. The Dy₃Si₂C₂ coated SiC powders were synthesized via an in-situ reaction between metal Dy and SiC in high temperature molten salts. The Dy₃Si₂C₂ coated SiC powder was sintered by spark plasma sintering (SPS), at 1800 ℃, 45 MPa. As the result, high-purity SiC ceramic with the density of 99% and thermal conductivity of 162.8 W·m ^-1·K ^-1was obtained to form the SiC-Dy₃Si₂C₂ raw material with n(Dy) : n(SiC)=1 : 4. Further study shows that Dy₃Si₂C₂ and SiC undergo a eutectic reaction at high temperatures, which generates liquid phase at the grain boundaries and promotes the densification of SiC ceramics. This study shows that the ternary rare-earth carbides Re₃Si₂C₂ (Re=La, Ce…) has great potential to be used as the sintering additive for SiC.