Zr-O Bond Research Articles

Spectroscopic insights on defects in self-irradiated natural Zircon: A natural analogue for slag host matrix for Zr-metallic wasteform

Zircon is a proposed slag host matrix associated with the metallic wasteform route developed for Zr-hull management. This study de-alienates the nature of radiation damage in Zr- and Si- sublattice in self-irradiated zircon matrices under long term of geological times using a natural analogue approach. To address this, self-irradiated reddish-brown zircon from Tamil Nadu, India was characterized using spectroscopic techniques such as X-ray Photoelectron Spectroscopy (XPS), Raman spectroscopy and Photoluminescence (PL) combined with Monte Carlo Based SRIM calculations. The observations revealed that the “as-received” zircon showed significant radiation damage primarily in the Si-sublattice (Si-O-Si linkages) while retaining its crystallinity, indicating a high degree of radiation resistance. The accumulated alpha-dose and displacements per atom (dpa) were evaluated to be 0.59 × 1018 decays/g and 0.019, respectively using RAMAN and SRIM calculations. Photoluminescence studies reveal that after annealing at 1673 K for 96 h, there was a partial recovery of radiation defects and a decrease in Si-O-Si bonds, although defects from dopant atoms remained unchanged. The damage observed is correlated with the nature of atomic bonding in Si-O and Zr-O bonds. The conclusions drawn suggest that zircon demonstrates considerable durability and selective recovery from radiation damage, making it a promising candidate for radioactive waste management.

Surface to bulk design empowering Ni-rich layered oxide cathode in sulfide-based All-Solid-State batteries

All-solid-state batteries (ASSBs) employing sulfide solid electrolytes (SSE) and high-nickel layered oxide cathodes have attracted considerable attention, attributed to their superior safety and great potential for high energy densities. However, the interface compatibility between SSE and nickel-rich oxide cathode remains a challenge. Here, a dual-functional strategy of Li6.25La3Zr2Al0.25O12 surface coating and bulk Zr doping in LiNi0.8Co0.1Mn0.1O2 was proposed (NCM811@CD-LLZAO), aiming to enhance the interfacial compatibility toward sulfide-based ASSBs. The fabricated ASSBs exhibit an impressive capacity retention rate of 91.1% after 100cycles at 0.1C and can sustain an ultra-long cycling performance over 1000cycles at 1.0C. Remarkably, even at a high rate of 11.0C, the battery still maintains a high capacity, highlighting its excellent rate performance. The distribution of relaxation time (DRT) analysis reveals that the LLZAO buffering layer can enhance the kinetics at the cathode/electrolyte interface. Theoretical calculation further confirms that the strong Zr-O bond formed by Zr doping can stabilize the lattice oxygen and effectively prevent the sulfide solid electrolyte from further electrochemical oxidation, thereby enhancing the interfacial dynamic and stability. These encouraging results provide a new strategy for the practical application of high-energy–density ASSBs, enabling fast charge transfer, extended cycle longevity and enhanced safety.

Achieving the Superior Abrasive Wear Resistance in ZTAP/Fe Composites from the Theoretical Calculations Guided Designing of Metallurgical Interface Transition Layer

Using the first-principles calculations and phonon QHA method, the thermodynamic stability, mechanical and thermophysical properties of binary Ni-Ti phases are obtained. The most thermodynamically feasible binary Ni3Ti phase with a superior elasticity and mechanical tensile strength is designed as the interfacial transition layer between ZTA ceramic particles and iron matrix. A high-Cr white cast iron matrix composite reinforced with ZTA particles is fabricated via infiltration casting process. The microstructures and three-body abrasive wear resistance of the composite are investigated. The obtained ZTAP/Fe composite has a compact metallic Ni3Ti metallurgical transition layer with a small amount of AlNi2Ti and TiO phases in the interfacial region, leading to a strongly adhesion between iron matrix and ZTA ceramic particles due to the presence of covalent Ti-O, Fe-O and Zr-O bonds. The composite exhibits the relative wear resistance 12.9 times higher than that of reference Cr15 specimen. The wear mechanism of the ZTAP/Fe composite is mainly attributed to the removal of iron matrix under the SiO2 abrasives, as revealed from the secondary electron images and laser scanning confocal topography.

Superior fast-charging Ni-rich cathode via promoted kinetic-mechanical performance

The sluggish Li-ion kinetics restrict the rapid charging capabilities and contribute to the structural deterioration of Ni-rich cathode materials. Notably, crack propagation during repeated charging cycles deteriorates the electrochemical stability, which hinders the further development of high-energy-density batteries for electric vehicles (EVs). In this paper, we proposed a simple yet effective method to enhance the Li-ion diffusion and mechanical properties of Ni-rich cathodes via straightforward Zr doping. In-situ high-rate XRD reveals that the detrimental uneven delithiation under the fast-charging process has been largely alleviated. Particularly, a robust structure with higher modulus and fracture strength is constructed owing to the higher Zr-O bond. By mitigating the kinetic hindrance and increasing the particle’s stiffness, the proposed Ni-rich cathode shows an impressive 97.6 % capacity retention under a 5 C rate current. This work provides a facile and efficient strategy for large-scale production of fast-charging Ni-rich cathode materials.

Garnet conductor network with Zr doping to implement surface bifunctional modification for Ni-rich cathodes

High‑nickel oxides are promising cathode materials for next-generation lithium batteries due to their high discharge capacity. LiNi0.83Co0.11Mn0.06O2(NCM83), a polycrystalline material widely used for its excellent performance, faces challenges such as interfacial side reactions and lattice oxygen release that hinder its electrochemical performance under high voltage. To promote the high-voltage performance of NCM83, Li7La3Zr2O12, a fast ion conductor with high conductivity and a wide electrochemical window, is taken into account. Here, the oxidation reaction and element diffusion are employed during high-temperature sintering to realize dual functional modification of NCM83 materials, including La-rich conductor network construction and near-surface Zr doping. Impressively, the modified electrode shows excellent cycling performance with 82.14 % retention after 200 cycles at 2.8–4.6 V, and splendid rate capability. Detailed studies reveal that ZrO bonds inhibit the migration of transition metal ions, preventing the distortion of the material structure. The surface ionic conductor network layer provides fast Li+ diffusion channels and protects the interfacial layer from electrolyte decomposition products. The facile Li7La3Zr2O12 modification method proposed in this paper is suitable for solving the interfacial and structural stability of cathode materials, offering hope for the application of high-energy lithium-ion batteries.

A multifunctional dual cation doping strategy to stabilize high-voltage medium-nickel low-cobalt lithium layered oxide cathode

High-voltage medium-nickel low-cobalt lithium layered oxide cathode materials are intriguing for lithium-ion batteries (LIBs) applications because of their relatively low cost and high capacity. Unfortunately, high charging voltage induces bulk layered structure decline and interface environment deterioration, low cobalt content reduces lithium diffusion kinetics, severely limiting the performance liberation of this kind of cathode. Here, a multifunctional Al/Zr dual cation doping strategy is employed to enhance the electrochemical performance of LiNi0.6Co0.05Mn0.35O2 (NCM) cathode at a high charging cut-off voltage of 4.5 V. On the one hand, Al/Zr co-doping weakens the Li+/Ni2+ mixing through magnetic interactions due to the inexistence of unpaired electrons for Al3+ and Zr4+, thereby increasing the lithium diffusion rate and suppressing the harmful coexistence of H1 and H2 phases. On the other hand, they enhance the lattice oxygen framework stability due to strong Al-O and Zr-O bonds, inhibiting the undesired H2 to H3 phase transition and interface lattice oxygen loss, thereby enhancing the stability of the bulk structure and cathode-electrolyte interface. As a result, Al/Zr co-doped NCM (NCMAZ) shows a 94.2 % capacity retention rate after 100 cycles, while that of NCM is only 79.4 %. NCMAZ also exhibits better rate performance than NCM, with output capacities of 92 mAh/g and 59 mAh/g at a high current density of 5C, respectively. The modification strategy will make the high-voltage medium-nickel low-cobalt cathode closer to practical applications.

Probing oxygen exchange between UiO-66(Zr) MOF and water using 17 O solid-state NMR.

The Zr-based Metal Organic Framework (MOF) UiO-66(Zr) is widely employed owing to its good thermal and chemical stabilities. Although the long-range structure of this MOF is preserved in the presence of water during several days, little is known about the formation of defects, which cannot be detected using diffraction techniques. We apply here 17 O solid-state NMR spectroscopy at 18.8 T to investigate the reactivity of UiO-66, through the exchange of oxygen atoms between the different sites of the MOF and water. For that purpose, we have selectively enriched in 17 O isotope the carboxylate groups of UiO-66(Zr) by using it with 17 O-labeled terephthalic acid prepared using mechanochemistry. In the presence of water at 50 °C and a following dehydration at 150 °C, we observe an overall exchange of O atoms between COO- and μ3 -O2- sites. Furthermore, we demonstrate that the three distinct oxygen sites, μ3 -OH, μ3 -O2- and COO- , of UiO-66(Zr) MOF can be enriched in 17 O isotope by post-synthetic hydrothermal treatment in the presence of 17 O-enriched water. These results demonstrate the lability of Zr-O bonds and the reactivity of UiO-66(Zr) with water.

Tailoring the structural and electro-optical properties of avisible-light emitting BaZrO3 photocatalyst: integrating DFT and comprehensive experimental analysis.

In the present work, the synthesis of BaZrO3 nano-ceramics is explored through flash combustion utilizing glycine as a fuel. The resulting nanoparticles exhibit a cubic Pm3̄m space group and a spherical morphology with an average size of 45.31 nm. XRD and EDAX verify the integrity of the phase. FTIR and Raman spectroscopy is used to analyze the molecular bonds and their vibrations, while XPS reveals surface compositions and oxidation states. The electro-optical properties of BaZrO3 are explored through UV-Vis spectroscopy and electronic band structure analysis. The Tauc plot displays a pair of band gaps, with values of 3.08 eV and 3.84 eV, corresponding to indirect and direct characteristics. BaZrO3 demonstrates photocatalytic potential with a degradation efficiency of approximately 36.41% for rhodamine B under visible light. Electronic band structure analysis reveals an indirect band gap of 3.05 eV in BaZrO3. The Bader analysis emphasizes the pronounced covalent characteristics present in the Zr-O bond. Photoluminescence spectra exhibit electronic transitions with a peak observed at 420.57 nm (∼2.94 eV), suggesting activity within the violet light spectrum. The CIE chromaticity coordinates imply prospective uses in the manufacture of violet-blue LEDs. These findings underscore the tailored properties of BaZrO3 nano-ceramics, showcasing their versatility for various applications, notably in advanced optoelectronic devices.

Realizing ferromagnetic semiconductors in SrRu1−xZrxO3 alloys

Using first principle calculations, we study the structural, electric and magnetic properties of SrRu1−xZrxO3 (0 ≤ x ≤ 1). The spin-polarization calculations present that SrRu1−xZrxO3 is a ferromagnetic metal at x = 0, a ferromagnetic semiconductor at x = 0.125, 0.25, an antiferromagnetic semiconductor at x = 0.5 and a nonmagnetic insulator at x = 1, which is in agreement with available experiments. As increasing Zr contents, the lattice parameters and band gaps of SrRu1−xZrxO3 increase while the energy difference between antiferromagnetic and ferromagnetic states decreases. Through Ru-O and Zr-O bonds, hybridization between Ru 4d and Zr 4d states near the Fermi level becomes strong. As a result, Ru 4d states split and then metal-insulator transition occurs at x = 0.125 due to Zr. Ferromagnetic semiconductors are first predicted in SrRu1−xZrxO3 alloys, which may have potential applications in spintronic devices.

Direct observation of charge density and electronic polarization in fluorite ferroelectrics by 4D-STEM

<p>The fluorite ferroelectrics is extremely promising for memory applications due to the silicon compatibility and the robust ferroelectricity with decreasing size. However, the direct observation of local electronic polarization remains elusive, thereby hindering the comprehension of the atomic-scale origin of ferroelectricity. Here, we directly map the real-space charge density of the ZrO<sub>2</sub> nanocrystal in its polar, nonpolar, as well as interphase regions with sub-?ngstr?m resolution by four-dimensional scanning transmission electron microscopy (4D-STEM). Based on the variation of the electric dipole moments, we analyze the electronic contribution to the total spontaneous polarization, which reaches a maximum of 17.8%. In comparison to the continuous polarization in conventional ferroelectric units, the local polarization profile looks like a maple leaf edge at the tetragonal-orthorhombic phase interface, which suggests a gradual increase in the electronic polarization and the covalent nature of the Zr-O bond. We validate these findings with 4D-STEM simulations and calculations based on density functional theory. These findings provide atomic insights into the bonding nature and phase transition feature in fluorite oxides, and unravel the likely origin of ferroelectricity in ferroelectrics.</p>

The controlled engineering of surface oxygen defects on Bi2Zr2O7 compounds for catalytic soot combustion by adjusting the preparation methods.

The quantity of surface oxygen vacancies/defects is critical to promote the reactivity of metal oxide catalysts. Therefore, for the controlled engineering of Bi2Zr2O7 with rich surface defects for soot combustion, four different methods have been adopted. Bi2Zr2O7 compounds with a defective fluorite phase but with varied surface vacancy concentrations have been successfully synthesized by various methods. The best catalyst (Bi2Zr2O7-CP) was fabricated by a facile co-precipitation method. Both O2- and O22- were the active surface sites whose number positively correlated to the number of surface oxygen vacancies and determined the activity. Moreover, a sample with more surface vacancies usually had weaker Zr-O bonds, which could be the intrinsic factor to enhance the activity. In addition, a novel and simple method has been developed to accurately titrate the absolute amount of soot reactive oxygen sites and calculate the TOF values. In conclusion, by optimizing the preparation methods, Bi2Zr2O7 catalysts with rich surface defects can be tuned, which may help in designing more applicable soot oxidation catalysts.

One-pot synthesis of novel mesoporous FeOOH modified NaZrH(PO4)2·H2O for the enhanced removal of Co(II) from aqueous solution.

One-pot synthesis of a novel mesoporous hydroxyl oxidize iron functional Na-zirconium phosphate (FeOOH-NaZrH(PO4)2·H2O) composites was firstly characterized and investigated its Co(II) adsorption from aqueous solution. Compared to NaZrH(PO4)2·H2O (65.7 mg⋅g-1), the maximum Co(II) adsorption capacity of FeOOH-NaZrH(PO4)2·H2O was improved to be 95.1 mg⋅g-1. BET verified the mesoporous structures of FeOOH-NaZrH(PO4)2·H2O with a larger pore volume than NaZrH(PO4)2·H2O. High pH values, initial Co(II) concentration, and temperature benefited the Co(II) adsorption. Kinetics, isotherms, and thermodynamics indicated an endothermic, spontaneous chemisorption process. FeOOH-NaZrH(PO4)2·H2O has a better Co(II) adsorption selectivity than that of NaZrH(PO4)2·H2O. In particular, FeOOH-NaZrH(PO4)2·H2O exhibited an outstanding reusability after ten cycles of tests. The main possible mechanism for adsorbents uptake Co(II) involved in ion exchange, electrostatic interaction, and -OH, Zr-O bond coordination based on FTIR and XPS analysis. This work presents a feasible strategy to prepare novel modified zirconium phosphate composites for extracting Co(II) from solutions and providing a new insight into the understanding of Co(II) adsorption in the real nuclear Co(II)-containing wastewater.

Effect of Zr4+ doping on the electrochemical properties of Na3MnTi(PO4)3/C cathode materials

NASICON structural materials have the advantages of structural stability, high ion conductivity, and high working potential, which have attracted widespread attention as cathode for sodium-ion batteries. Although the three-electron reaction in the NASICON structure Na3MnTi(PO4)3 increases the specific capacity of the material, poor electronic conductivity remains a key factor restricting its practical application. Herein, Na3Mn1-xZrxTi(PO4)3/C (x = 0, 0.01, 0.03, 0.05, 0.07 and 0.1), a typical three-dimensional NASICON structure cathode material for sodium-ion batteries, was synthesized by the sol-gel method. Through powder X-ray diffraction, the Zr4+ doping in the Na3MnTi(PO4)3 (NMTP) structure was verified. It was found that doping trace amounts of Zr at the Mn site can not only reduce the Jahn-Teller effect caused by Mn3+, but also strengthen the Zr-O bond compared to the Mn-O bond, making the crystal structure more stable by reducing the proportion of Mn. According to the findings of the EIS test, a suitable amount of Zr doping can enhance the electronic conductivity and Na ion diffusion coefficient of NMTP/C electrode materials, weaken polarization phenomena, increase electrode reaction rate, and significantly improve the rate performance and cycling performance of Na3Mn1-xZrxTi(PO4)3 material. The Na3Mn1-xZrxTi(PO4)3/C sample prepared has high initial capacity of 124mAh/g, a capacity retention rate of 86 % after 200 cycles at 0.2C, and a capacity retention rate of 84 % after 500 cycles at 1C. This proves that the material still exhibits excellent cycling stability and structural stability after high current cycling. More importantly, the Na3Mn0.95Zr0.05Ti(PO4)3 (Zr5-NMTP)//Hard carbon full battery also exhibits ideal electrochemical performance.

Boosting toluene deep oxidation by tuning metal-support interaction in MOF-derived Pd@ZrO2 catalysts: The role of interfacial interaction between Pd and ZrO2

The regulation of metal-support interaction is one of the productive strategies to enhance volatile organic compounds (VOCs) deep degradation. Herein, Pd@ZrO2 catalysts were synthesized via using in-situ growth Zr-based metal organic framework (MOF) Pd@UiO-66 as the precursor to boost toluene deep degradation. Compared with Pd@ZrO2-Zr(OH)4 synthesized by using Zr(OH)4 as the precursor, MOF-derived Pd@ZrO2 catalysts with different calcination time exhibited more superior catalytic performance, water-resistance and stability. Characterizations results indicated the occurrence of interfacial interaction in MOF-derived Pd@ZrO2 induced the better reducibility at low-temperature and the generation of oxygen vacancies, enhanced Oads species content, weakened Zr-O bond strength, improved the mobility of Olat species, which caused its better toluene degradation performance. Simultaneously, in-situ diffuse reflectance infrared Fourier transform spectroscopy results clarified that the interfacial interaction heightened the adsorption and activation ability for gaseous oxygen to form reactive oxygen species and replenish consumed Olat species, promoted toluene ring-opening reaction, reduced benzoate acid species cumulation, expedited the fast deeply degradation of toluene to CO2 and H2O. This work may provide a new perspective on MOF-derived catalysts with better performance for VOCs degradation deeply by tuning interfacial interaction.

Insights into service-derived Zr-Ta-O film: Morphology evolution, temperature resistance, and atomic bonding

Entropy-stabilized ceramics for ultra-high temperature oxidation protection are springing up, accompanied by complex morphology characteristics and elusive protective mechanisms. Herein, how the Ta/Zr molar ratio change affected the morphology evolution, temperature resistance, and atomic bonding of Zr-Ta-O film was revealed, which was expected to deepen the understanding on A-B-O protective film (A = Hf, Zr; B = Ta, Nb). The Zr-Ta-O film was constructed on the thermally sprayed ZrC-TaC coating utilizing oxyacetylene ablation. Morphological characteristics of the Zr-Ta-O film were found highly related to Ta/Zr molar ratios. The long-term temperature endurance limit of the service-derived Zr-Ta-O film was considered below 2000 ℃, affected by the consumption of micro-scale Ta-rich regions under high-temperature gas scouring (∼2800 ℃, 5–8 m/s). The phenomena were well explained by the binding energy difference (Ta-doped t-ZrO2 and Zr-doped α-Ta2O5) and fluctuation law of Zr-O bond length with Ta/Zr molar ratio increasing (from local instability to whole instability).

Chemical regulation in the bonding reconstruction stage of amorphous Zr-Si oxidation and the resultant phase selection

A mechanism based on oxidation induced bonding reconstruction (OBR) was proposed to optimize phase selection during oxidation of amorphous ZrxSi1−x (0.55 ≤ x ≤ 0.75). According to VASP modeling, a self-barrier effect was proposed to regulate the OBR and Zr/Si separation at initial oxidation stage. The depressed Si inner-diffusion leads to the formation of amorphous bilayer structure. A Si-rich Zr-Si layer formed underneath the outer Zr-Si-O amorphous layer, which synergistically impeded oxygen permeation at subcritical environment. As confirmed by EELS and XPS, the alternative of Zr-O and Si-O bonds in Zr-Si-O layer contributed to the enhanced hydro chemical stability.

Enhanced CO2 adsorption of PEHA/sepiolite adsorbent by zirconium accelerator in post-combustion

The most promising approach to tackling the greenhouse gases is CO2 capture and storage (CCS), and amine solid adsorbents are the most widely investigated materials. In this work, Zr species as an accelerator promote CO2 adsorption of the Pentatethylenehexamine (PEHA)/sepiolite (SEP) adsorbents. The adsorption rate, CO2 adsorption capacity, and amine efficiency were significantly improved under various conditions (temperature, gas flow, and CO2 concentration) by the introduction of the optimal content of Zr, the optimal HSEP-Zr0.13-PEHA0.5-600 adsorbent exhibited 1.80 mmol/g at 60 °C. Adsorption experiments combine with characterization (TG, XPS, NH3-TPD, SEM and TEM) exhibited that the introduction of Zr species were high dispersion on sepiolite, and Zr-O bond was formed in the structure of sepiolite. The acidity of the sepiolite supporter was enhanced by Zr which is benefit for amine loading. Above all resulted in the regeneration and thermal stability of the adsorbent were improved together. The economic evaluation results demonstrated that the adsorbent with Zr species is low-cost for large-scale post-combustion CO2 capture.

Enhanced performances of a-IGZO TFTs with oxide passivation layers fabricated by hollow cathode assisted PLD

Pulsed laser deposition (PLD) and two-step thermal annealing are combined to fabricate MgO, TiO2, Y2O3, Al2O3, ZrO2 and HfO2 passivation layers on a-IGZO TFTs. The influences of the passivation layers on the electrical properties are investigated. It is found that conventional PLD is sufficient to deposit high-quality Y2O3 and ZrO2 passivation layers, but hollow cathode assisted PLD (HC-PLD) should be employed to solve the oxygen deficiency in MgO, TiO2, Al2O3, and HfO2 thin films by oxygen plasma. Furthermore, two-step annealing is adopted to improve the performances of the devices: Firstly, a-IGZO thin films are pre-annealed to enhance the carrier mobility. Secondly, the passivation layers are deposited on a-IGZO and the whole structures are post-annealed to endow the good on-off performance. The sharp a-IGZO/passivation interfaces remain after thermal annealing. The Hall mobility is mainly restricted by the scattering of metal ions at the a-IGZO/passivation interface. TiO2 passivated devices exhibit the highest Hall mobility of 16.7 cm2V−1s−1, owing to the smaller cation charge. The threshold voltage stability under positive gate bias is dependent on the metal-oxygen bond strength in the passivation layers. ZrO2 passivated devices have the lowest threshold voltage shift, beneficial from the strong Zr-O bonds. The subthreshold performance and the stability under illumination are determined by the oxygen vacancies at a-IGZO/passivation interfaces and ZrO2 passivated devices exhibit the lowest subthreshold swing and the best illumination stability.

Relationship analyses on environmental factors-ablation performance based on ZrC-TaC system: Oxygen partial pressure and gas flow scouring

For better understanding on effects of ablation environmental factors (oxygen partial pressure P(O2) and gas flow scouring), multiple experiments and multiscale simulations based on thermally sprayed ZrC-TaC system were conducted. High P(O2) was found helpful to accelerate Ta2O5/ZrO2 mutual diffusion by variable P(O2) oxidation at 1500 ℃ (5-50 kPa). Effects of gas flow scouring was evaluated by flow filed simulation coupling laser and oxyacetylene ablations, from which its promotion effect on Ta2O5/ZrO2 diffusion efficiency was found. The increased Ta2O5/ZrO2 diffusion efficiency will accelerate the structure instability of Ta doped c-ZrO2 skeletons due to Zr-O bond length extension around Ta atoms.

Zr4+ and glutaraldehyde cross-linked polyethyleneimine functionalized chitosan composite: Synthesis, characterization, Cr(VI) adsorption performance, mechanism and regeneration

In order to improve the stability, electrostatic interaction and ion exchange ability of chitosan for Cr (VI) removal, it is an effective strategy to introduce polyvalent metal ions and polymers into chitosan molecular chain through crosslinking. In this paper, Zr4+ and glutaraldehyde crosslinked polyethyleneimine functionalized chitosan (CGPZ) composite was successfully synthesized and characterized by XRD, SEM, FTIR, BET, and XPS. The results showed that polyethyleneimine was successfully grafted onto chitosan by Schiff base reaction, while the appearance of ZrO and ZrN bonds verified the successful preparation of CGPZ. The monolayer maximum adsorption capacity of Cr(VI) by CGPZ was 593.72 mg g−1 at 298 K and t = 210 min. The removal efficiency of 100 mg L−1 Cr(VI) reached 95.7 %. The thermodynamic, isotherm and kinetic results show that the adsorption process of Cr (VI) by CGPZ is a spontaneous endothermic process controlled by entropy, which accords with Freundlich model and pseudo-second-order kinetic model. The regeneration experiments show that both HCl and NaOH can effectively desorb Cr(III) and Cr(VI) from the adsorbent surface, and the adsorbent has good acid-base resistance and regeneration performance. The removal of Cr(VI) mainly involves electrostatic attraction, ion exchange, reduction and complexation. CGPZ can synergistically adsorb Cr(VI) by electrostatic interaction of -NH2/-C=N and ion exchange of Cl− ion in the center of Zr, then reduce Cr(VI) to Cr(III) (45.4 % at pH = 2.0) by the -OH group on its surface, and chelate Cr(III) through COO- and -NH- groups.