Trisodium Citrate as a Double-Edged Sword: Selective Etching Prussian Blue Analog Nanocubes into Orthogonal Frustums and Their Derivatives for Supercapacitors.

The construction of novel structured Prussian blue analogs (PBAs) by chemical etching has attracted the most attention to PBA derivatives with outstanding performance. In this work, the unprecedented PBA orthogonal frustums are first prepared from nanocubes through a selective chemical etching approach using trisodium citrate as an etchant. The citrate ions can chelate with nickel species from the edges/corners of NiCo-PBA nanocubes and then disintegrate NiCo-PBAs resulting in the generation of NiCo-PBA orthogonal frustums. The derived CoNi2S4/Co0.91S composites still inherit the original orthogonal frustum structure and possess outstanding supercapacitor performance. This study develops a popularized method to construct novel structured PBAs and brings inspiration for designing PBA-based electrodes with advanced electrochemical performance.

Anionic Biopolymer Assisted Preparation of MoO2@C Heterostructure Nanoparticles with Oxygen Vacancies for Ambient Electrocatalytic Ammonia Synthesis.

Recently, Mo-based metal catalysts are widely applied in the electrocatalytic nitrogen reduction reaction (NRR) due to the lower binding energy between the Mo atom and N atom. The design of a Mo-based catalyst@carbon heterostructure and the introduction of anion vacancies are effective measures to improve their NRR performance. In this research, the cross-linked Vo-MoO2@C (Vo means oxygen vacancies) heterostructure nanoparticles with rich oxygen vacancies are first synthesized via pectin assisted hydrothermal reaction followed by calcination and treating with NaBH4 solution. Vo-MoO2@C exhibits good electrocatalytic NRR performance with an ammonia yield rate of 9.75 µg h-1 mg-1 at -0.5 V (RHE) and a Faraday efficiency (FE) of 3.24% at -0.3 V (RHE) under ambient conditions.

Three-Dimensional Hierarchical Porous Carbon Cathode Derived from Waste Tea Leaves for the Electrocatalytic Degradation of Phenol.

Tea leaves have been explored as an economically viable and environmentally friendly source of biomass carbon. Tea leaf porous carbon (TPC) with a three-dimensional (3D) structure was prepared by a potassium hydroxide pretreatment and high-temperature calcination method, and the preparation process was simple and self-templating. The prepared TPC has a large specific surface area (1620.05 m2 g-1), three-dimensional multilayer pore structure, uniform pore size, and high oxygen content (15.51%). Both the calcination temperature and the activation level have an effect on the structure and performance of the TPC. The TPC electrode can generate a large amount of hydrogen peroxide in the initial stage of the degradation process, thereby increasing the amount of hydroxyl radicals generated and removing organic pollutants. Therefore, phenol was used to test the degradation effects and evaluate the degradation performance of TPC. Under suitable degradation conditions, TPC-800-2 showed a 95.41% degradation rate after 120 min of degradation, which is superior to that of other calcination temperatures and activation levels. The removal efficiency of chemical oxygen demand after 180 min was 90.0% and showed good stability after being used 20 times. Our work illustrates that a simple, high-performance self-templating synthetic strategy for producing novel 3D-TPC from biomass sources can play a significant role in the actual wastewater treatment of other biomass materials.

Flower-like Ni/Mn/MC microspheres derived from metal-organic frameworks for electrocatalytic degradation of ceftriaxone sodium.

This study demonstrated the design and fabrication of flower-like Ni/Mn-MOFs materials, and three-dimensional ultrathin flower-like Ni/Mn/MC microspheres were fabricated by embedding metal or metal oxide nanoparticles into a porous carbon skeleton via high-temperature pyrolysis at 600 °C and used for the electrocatalytic degradation of ceftriaxone sodium. This unique ultrathin porous flower-like structure can expose more active sites, provide rapid ion/electron transfer, and improve electrocatalytic activity. Meanwhile, the excellent electrical conductivity of the carbon skeleton, as well as the rational composition and synergistic effect of the two components, can promote the generation of active radicals (•OH and •O2-) in the reaction system, which accelerates the electrochemical degradation process and improves the electrocatalytic degradation performance. The results showed that the Ni/Mn/MC-5:1 composite prepared when the molar ratio of Ni: Mn was 5:1 exhibited the best electrocatalytic degradation performance for the degradation of sodium ceftriaxone. The composites showed 98.2% degradation of ceftriaxone sodium in 120 min and maintained sound degradation after 20 cycles. Therefore, we concluded that this novel multicomponent composite has good electrocatalytic activity and stability for the degradation of antibiotic wastewater.

Construction of CoNi2S4/Co9S8@Co4S3 nanocubes derived from Ni-Co prussian blue analogues@cobalt carbonate hydroxide core-shell heterostructure for asymmetric supercapacitor.

Construction of Prussian blue analogues (PBAs) with heterostructure is beneficial to preparing PBAs derivatives with superior electrochemical performance. In this work, the core-shell nanostructured nanocubes composed of nickel hexacyanocobalt PBA (NiCo-PBA)@cobalt carbonate hydroxide (CCH) are synthesized through an in-situ epitaxial growth strategy, and the formation mechanisms of coating are carefully validated and specifically discussed. Then, the precursors are successfully transformed into hierarchical CoNi2S4/Co9S8@Co4S3 via the gas-phase vulcanization method. Benefiting from the intriguing heterostructure and multicomponent sulfides, the CoNi2S4/Co9S8@Co4S3-80 electrode exhibits a high specific capacity of 799 ± 16C/g (specific capacitance of 1595 ± 31F/g) at 1 A/g, ultra-high capacity retention of 80 % at a high current density of 20 A/g. The assembled asymmetric supercapacitor (ASC) device delivers a high energy density of 43.3 Wh kg-1 at a power density of 899 W kg-1 and exhibits superior cycling stability with the capacity retention of 88 % after 5,000 cycles. Subsequently, the fabricated all-solid-state ASC device shows an excellent energy density of 36.4 Wh kg-1 with a power density of 824 W kg-1. This work proposing rational design of combining multicomponent sulfides and core-shell heterostructure based on PBA nanocubes opens up a novel route for developing asymmetric supercapacitor electrode materials with superior performance.

Coral-like Fe-doped MoO2/C heterostructures with rich oxygen vacancies for efficient electrocatalytic N2 reduction.

Molybdenum (Mo) is one of the most important constituent elements in natural nitrogenase and theoretical calculation results show that Mo-based materials can be used as potential NRR electrocatalysts. The design of advanced catalysts with a special structure is very essential for promoting the development of electrocatalytic N2 into NH3. In this paper, Fe-doped MoO2/C heterostructured nanoparticles with rich oxygen vacancies (Vo) are designed and they exhibit highly efficient catalytic activity for artificial N2 fixation in neutral electrolytes under ambient conditions. The influence of the atomic ratio of the Fe source to the Mo source and the NaBH4 ethanol solution treatment on the structure and electrocatalytic performance are systematically investigated. The Vo-Fe-MoO2/C (1 : 50) catalyst with rich oxygen vacancies shows a satisfactory electrocatalytic N2 reduction reaction (e-NRR) activity in 0.1 M Na2SO4 with a high ammonia yield rate of 15.87 ± 0.3 µg h-1 mg-1 at -0.5 V versus the reversible hydrogen electrode (vs. the RHE) and a FE of 13.4% at -0.3 V (vs. the RHE). According to the results of DFT calculations, the active center of the electro-catalytic nitrogen reduction reaction is the molybdenum atom between the iron atom and the O vacancy. Oxygen vacancies can not only reduce the energy barrier of the RDS but also facilitate the desorption of ammonia and the first step hydrogenation of nitrogen. The doping of Fe will change the electronic state of the Mo atom in MoO2.

Synthesis of novel Fe0-Fe3O4/CeO2/C composite cathode for efficient heterogeneous electro-Fenton degradation of ceftriaxone sodium.

Fe0-Fe3O4 nanoparticles and cerium dioxide hollow spheres as efficient heterogeneous electro-Fenton reagents were rationally designed to be embedded in porous carbon derived from skimmed cotton for the electrocatalytic degradation of ceftriaxone sodium. Skimmed cotton porous carbon material has a hollow tubular structure, and cerium dioxide is dispersed on the surface of the carbon material in a hollow sphere structure of uniform size. Fe0-Fe3O4 nanoparticles were wrapped in irregular particle shapes on the surface of cerium dioxide hollow spheres, and the remaining part was laid flat on the surface of porous carbon material. The as-synthesized Fe0-Fe3O4/CeO2/C showed excellent degradation efficiency of 95.59 % for ceftriaxone sodium within 120 mins and obtained a COD removal rate of 95.21 % at 240 mins. The zero-valent iron as a reducing agent effectively accelerated the Fe3+/Fe2+ cycle, allowing the composites to exhibit higher catalytic activity and further reducing the possibility of secondary contamination. Moreover, the existence of cerium dioxide further promoted the redox cycle of Ce4+/Ce3+ and accelerated the electron transfer in the interface of the catalyst. The synergistic effect of iron and cerium greatly facilitated the production of hydroxyl radicals and increased the yield of hydroxyl radicals in the reaction system.

Facile synthesis of multifunctional pharmaceutical carbon dots for targeted bioimaging and chemotherapy of tumors.

Drug-derived carbon dots (CDs) not only have excellent photoluminescence properties of CDs, but also maintain pharmacological effects of original drugs, so as to realize extended applications for both bioimaging and chemotherapy. In this work, metformin (Met)-derived CDs (Met-CDs) as multifunctional nanocarriers with tumor cell imaging and cancer therapy are synthesized using Met and citric acid as precursors. The created Met-CDs exhibit obvious resistance to photobleaching, significant pH sensitivity in acidic environments, good pH stability in alkaline environments, and high temperature sensitivity. In addition, we further investigate the biological activity of Met-CDs using diabetic cell models, which demonstrate the ability of Met-CDs to treat diabetes and reduce the production of reactive oxygen species in diseased cells. Subsequently, human alveolar adenocarcinoma basal epithelial cells (A549) are cultured in both normal glucose and low glucose media, and different concentrations of Met and Met-CDs are added to investigate the effect of Met-CDs on A549 cells. Finally, we successfully utilize the prepared Met-CDs to image live A549 cells in vitro in normal glucose medium. The Met-CDs prepared in this work reveal high potential to be used as both fluorescent probes and drug agents for tumor therapy, realizing controllable integrated diagnosis and treatment of diseases.

Regulation of multi-color fluorescence of carbonized polymer dots by multiple contributions of effective conjugate size, surface state, and molecular fluorescence.

Fluorescent carbon dots (CDs)-based nanomaterials exhibited promising potential in the fields of biomedicine, bioanalysis, and biosensors. In this work, multi-colored fluorescent carbonized polymer dots (CPDs) ranging from blue to red are obtained using different synthesis methods using citric acid and urea as raw materials, and the controllable synthesis of CPDs with multi-color fluorescence is successfully realized. Then, the photoluminescence (PL) mechanism of CPDs is studied using multiple characterization methods, and the key factors affecting the fluorescence emission wavelength of CPDs are discussed. It is shown that the fluorescence of the CPDs originates from three main components: the carbon nuclei in the intrinsic state, the functional groups in the surface state, and the molecular fluorophores adsorbed on the surface of the CPDs. The reaction temperature and reaction time affect the effective conjugation size of the carbon nuclei, which in turn affects the fluorescence redshift of CPDs; the reaction solvent greatly alters the surface state of CPDs (e.g. surface defects and functional groups), which leads to a significant redshift in the fluorescence of CPDs; the presence of molecular fluorophores facilitates the fluorescence redshift of CPDs. Finally, we have successfully applied the prepared red fluorescent CPDs for in vitro cell imaging. The study on the color regulation mechanism of CPDs is of great significance for the controllable preparation of high-performance fluorescent CDs and their application in the field of biomedicine.

Flower-like molybdenum disulfide decorated ZIF-8-derived nitrogen-doped dodecahedral carbon for electro-catalytic degradation of phenol.

In this work, flower-like molybdenum disulfide was constructed on the surface of ZIF-8-derived nitrogen-doped dodecahedral carbon (ZNC) for the electrocatalytic degradation of phenol. The flower-like nanostructure of MoS2@ZNC contributed to the exposure of more edge-active sites of MoS2. At the same time, Mo4+ and Mo6+ co-existed in MoS2@ZNC, which promoted the generation of H2O2 and •OH, and improved the catalytic activity of composite materials. In addition, electrochemical performance analysis showed that MoS2 loaded on the surface of ZNC significantly improved the redox capacity of the material, and the composite ratio of MoS2 and ZNC affected the structure and properties of MoS2@ZNC composites. Moreover, the electrochemical performance of prepared MoS2@ZNC was evaluated by the generation of hydroxyl (•OH) and the degradation efficiency of phenol. The results showed that MoS2@ZNC-2 had an excellent phenol degradation efficiency (98.8%) and COD removal efficiency (86.8%) within 120 min. Furthermore, MoS2@ZNC cathode still maintained good performance after being experimented with 20 times, indicated the excellent stability of MoS2@ZNC.

In-situ ZnO template preparation of coal tar pitch-based porous carbon-sheet microsphere for supercapacitor.

Three-dimension (3D) porous carbon-sheet microspheres (PCSMs) are prepared through coating coal tar pitch on basic zinc carbonate microspheres followed by in situ ZnO template carbonization and KOH activation. The as-prepared PCSMs show microsphere morphology composed of petal-like carbon nanosheets, which have large specific area (1359.88-2059.43 m2 g-1) and multiscale pores (mainly micropores and mesopores). As the supercapacitor electrodes, the 3D PCSMs present a good electrochemical performance with a large specific capacitance of 313 F g-1 at 1 A g-1 and high rate capability of 81.9% capacitance retention when increasing the current density up to 50 A g-1 in a three-electrode system. In addition, the energy density can reach up to 18.79 Wh kg-1 at a high power density of 878.4 W kg-1 for PCSMs-0.2a symmetrical supercapcitor in 1 M Na2SO4 electrolyte.

Highly fluorescent carbon dots as novel theranostic agents for biomedical applications.

As an emerging fluorescent nanomaterial, carbon dots (CDs) exhibit many attractive physicochemical features, including excellent photoluminescence properties, good biocompatibility, low toxicity and the ability to maintain the unique properties of the raw material. Therefore, CDs have been intensively pursued for a wide range of applications, such as bioimaging, drug delivery, biosensors and antibacterial agents. In this review, we systematically summarize the synthesis methods of these CDs, their photoluminescence mechanisms, and the approaches for enhancing their fluorescence properties. Particularly, we summarize the recent research on the synthesis of CDs from drug molecules as raw materials and introduce the representative application aspects of these fascinating CDs. Finally, we look into the future direction of CDs in the biomedical field and discuss the challenges encountered in the current development.

Effective electro-Fenton-like process for phenol degradation on cerium oxide hollow spheres encapsulated in porous carbon cathode derived from skimmed cotton.

The uniform size cerium dioxide hollow spheres which were prepared by the SiO2 hard template method were loaded on microporous porous carbon obtained by carbonization derived from skimmed cotton (CSC) for electro-Fenton-like degradation of phenol. The microstructures of CSC/CeO2 composite materials were characterized utilizing XRD, BET, XPS, SEM, and TEM. The electrochemical performance of the CSC/CeO2 cathodes was studied through cyclic voltammetry and electrochemical impedance spectroscopy. The prepared CSC has a hollow tubular structure, and cerium dioxide is evenly loaded on the surface of the CSC in the form of uniform-sized hollow spheres. The CSC/CeO2 materials have a great specific surface area (287.73 m2 g-1) and a uniform poresize. The electrochemical performance analysis demonstrated that the redox ability of the material greatly was improved by loading CeO2 on the porous carbon surface of the skimmed cotton. The load ratio of cerium dioxide hollow spheres affects the structure and properties of CSC/CeO2 materials. Ce3+ and Ce4+ were co-existed in CSC/CeO2, which promoted the generation of H2O2 and .OH, and improved the catalytic activity of composite materials. The degradation efficiency of phenol reached 97.6% in 120 min, and the CSC/CeO2 cathode manifested excellent stability after being experimented 20 times. CSC/CeO2 composite material has great practical value in the treatment of phenolic wastewater and has promise for further application.

Nickel and cobalt metal-organic-frameworks-derived hollow microspheres porous carbon assembled from nanorods and nanospheres for outstanding supercapacitors.

The development of efficient electrode materials is essential to promote the performance of energy storage equipment. Nowadays, metal organic frameworks (MOFs) have been widely regarded as active materials for supercapacitors mainly thanks to their adjustable structure and outstanding porosity. Here, highly optimized Nickel and Cobalt MOF-derived N-doped porous carbon (Ni/Co-MOF-NPC) are considered the best choice for electrode materials due to their unique structural properties and excellent electrochemical performance. Pure cobalt oxide rarely reaches a specific capacitance of 104.3 F g-1 when the current density is 1 A g-1, but the optimized Ni/Co-MOF-NPC-2:1 offers an ultra-high specific capacitance of 1214 F g-1, which is much higher than that of pure cobalt oxide in a three-electrode test system. When the current density is 10 A g-1, after 6000 cycles, the capacitance can still maintain 98.8% of the initial capacitance. Asymmetric supercapacitors were assembled using the prepared Ni/Co-MOF-NPC-2:1 as the positive electrode material, corrugated paper activated carbon (CPAC) as the negative electrode material, the prepared Ni/Co-MOF-NPC-2:1//CPAC exhibits an outstanding energy density of 55.4 Wh kg-1 at 758.5 W kg-1, and has a significant cycle stability of 75.2% retention after 20,000 cycles. This excellent MOF synthesis strategy reduced the gap between the experimental synthesis and practical application of MOF in fast energy storage.

Biowaste-based porous carbon for supercapacitor: The influence of preparation processes on structure and performance.

Here, a series of porous carbon based supercapacitor electrode materials have been synthesized by means of pyrolysis and hydrothermal methods combining with KOH activation using the biomass wastes mung bean husks as resources. The influence of synthesis process on the morphology, structure and supercapacitor performance of mung bean husks derived porous carbons has been investigated systematically. Especially, it is found that these oxygen-containing groups on the biochar play a crucial role in fabricating the three-dimensional (3D) hierarchical porous structure carbon. The original bio-structured porous carbon (PC3-600), the 3D architecture porous carbon (HPC2-700) and the porous carbon block (HPPC2-700) have a high specific surface area, and the former mainly contains micropores and the latter two possess multistage pores. The specific capacitance of PC3-600, HPC2-700 and HPPC2-700 is respectively up to 390 F g-1, 353 F g-1, 304 F g-1 at 1 A g-1, and still maintains as high as 287 F g-1, 270 F g-1 and 235 F g-1 with corresponding retention ratio of 73.5%, 76.48%, 77.3% even at a high current density of 50 A g-1. HPC2-700//HPC2-700 symmetric supercapacitor achieves a high energy density of 20.4 Wh kg-1 at 872 W kg-1 in 1 M Na2SO4 electrolyte.

Preparation of RuO2-TiO2/Nano-graphite composite anode for electrochemical degradation of ceftriaxone sodium.

Graphite-like material is widely used for preparing various electrodes for wastewater treatment. To enhance the electrochemical degradation efficiency of Nano-graphite (Nano-G) anode, RuO2-TiO2/Nano-G composite anode was prepared through the sol-gel method and hot-press technology. RuO2-TiO2/Nano-G composite was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and N2 adsorption-desorption. Results showed that RuO2, TiO2 and Nano-G were composited successfully, and RuO2 and TiO2 nanoparticles were distributed uniformly on the surface of Nano-G sheet. Specific surface area of RuO2-TiO2/Nano-G composite was higher than that of TiO2/Nano-G composite and Nano-G. Electrochemical performances of RuO2-TiO2/Nano-G anode were investigated by cyclic voltammetry, electrochemical impedance spectroscopy. RuO2-TiO2/Nano-G anode was applied to electrochemical degradation of ceftriaxone. The generation of hydroxyl radical (OH) was measured. Results demonstrated that RuO2-TiO2/Nano-G anode displayed enhanced electrochemical degradation efficiency towards ceftriaxone and yield of OH, which is derived from the synergetic effect between RuO2, TiO2 and Nano-G, which enhance the specific surface area, improve the electrochemical oxidation activity and lower the charge transfer resistance. Besides, the possible degradation intermediates and pathways of ceftriaxone sodium were identified. This study may provide a viable and promising prospect for RuO2-TiO2/Nano-G anode towards effective electrochemical degradation of antibiotics from wastewater.

Study on preparation of SnO2-TiO2/Nano-graphite composite anode and electro-catalytic degradation of ceftriaxone sodium.

In order to improve the electro-catalytic activity and catalytic reaction rate of graphite-like material, Tin dioxide-Titanium dioxide/Nano-graphite (SnO2-TiO2/Nano-G) composite was synthesized by a sol-gel method and SnO2-TiO2/Nano-G electrode was prepared in hot-press approach. The composite was characterized by X-ray photoelectron spectroscopy, fourier transform infrared, Raman, N2 adsorption-desorption, scanning electrons microscopy, transmission electron microscopy and X-ray diffraction. The electrochemical performance of the SnO2-TiO2/Nano-G anode electrode was investigated via cyclic voltammetry and electrochemical impedance spectroscopy. The electro-catalytic performance was evaluated by the degradation of ceftriaxone sodium and the yield of ·OH radicals in the reaction system. The results demonstrated that TiO2, SnO2 and Nano-G were composited successfully, and TiO2 and SnO2 particles dispersed on the surface and interlamination of the Nano-G uniformly. The specific surface area of SnO2 modified anode was higher than that of TiO2/Nano-G anode and the degradation rate of ceftriaxone sodium within 120 min on SnO2-TiO2/Nano-G electrode was 98.7% at applied bias of 2.0 V. The highly efficient electro-chemical property of SnO2-TiO2/Nano-G electrode was attributed to the admirable conductive property of the Nano-G and SnO2-TiO2/Nano-G electrode. Moreover, the contribution of reactive species ·OH was detected, indicating the considerable electro-catalytic activity of SnO2-TiO2/Nano-G electrode.

Construction of 3D nanostructure hierarchical porous graphitic carbons by charge-induced self-assembly and nanocrystal-assisted catalytic graphitization for supercapacitors.

A smart and sustainable strategy based on charge-induced self-assembly and nanocrystal-assisted catalytic graphitization is explored for the efficient construction of 3D nanostructure hierarchical porous graphitic carbons from the pectin biopolymer. The electrostatic interaction between the negatively charged pectin chains and magnesium ions plays a crucial role in the formation of 3D architectures. The 3D HPGCs possess a three-dimensional carbon framework with a hierarchical porous structure, flake-like graphitic carbon walls and high surface area (1320 m(2) g(-1)). The 3D HPGCs show an outstanding specific capacitance of 274 F g(-1) and excellent rate capability with a high capacitance retention of 85% at a high current density of 50 A g(-1) for supercapacitor electrodes. This strategy provided a novel approach to effectively construct 3D porous carbon nanostructures from biopolymers.

Pretreatment of apramycin wastewater by catalytic wet air oxidation.

The pretreatment technology of wet air oxidation (WAO) and coagulation and acidic hydrolysis for apramycin wastewater was investigated in this paper. The COD, apramycin, NH4+ concentration, and the ratio of BOD5/COD were analyzed, and the color and odor of the effluent were observed. WAO of apramycin wastewater, without catalyst and with RuO2/Al2O3 and RuO2-CeO2/Al2O3 catalysts, was carried out at degradation temperature of 200 degrees C and the total pressure of 4 MPa in a 1 L batch reactor. The result showed that the apramycin removals were respectively 50.2% and 55.0%, COD removals were 40.0% and 46.0%, and the ratio of BOD5/COD was increased to 0.49 and 0.54 with RuO2/Al2O3 and RuO2-CeO2/Al2O3 catalysts in catylytic wet air oxidation (CWAO) after the reaction of 150 min. With the pretreatment of coagulation and acidic hydrolysis, COD and apramycin removals were slight decreased, and the ratio of BOD5/COD was increased to 0.45, and the effluents was not suitable to biological treatment. The color and odor of the wastewater were effectively controlled and the reaction time was obviously shortened with WAO. HO2 may promote organic compounds oxidized in WAO of the apramycin wastewater. The addition of CeO2 could promote the activity and stability of RuO2/Al2O3 in WAO of apramycin wastewater.

Kinetics study on catalytic wet air oxidation of phenol by several metal oxide catalysts.

Four metal oxide catalysts composed of copper (Cu), stannum(Sn), copper-stannum (Cu-Sn) and copper-cerium(Cu-Ce) respectively were prepared by the co-impregnation method, and gamma-alumina (gamma-Al2O3) is selected as support. A first-order kinetics model was established to study the catalytic wet air oxidation of phenol at different temperature when these catalysts were used. The model simulations are good agreement with present experimental data. Results showed that the reaction rate constants can be significantly increased when catalysts were used, and the catalyst of 6% Cu--10% Ce/gamma-Al2O3 showed the best catalytic activity. This is consistent with the result of catalytic wet air oxidation of phenol and the COD removal can be arrived at 98.2% at temperature 210 degrees C, oxygen partial pressure 3 MPa and reaction time 30 min. The activation energies of each reaction with different catalysts are nearly equal, which is found to beabout 42 kJ/mol and the reaction in this study is proved to be kinetics control.