INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
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2025
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IF 4.6
Bin Li,Hongyu Ren,Shengda Guo,Jianbo Zhang,Zhihui Zhou,Bin Zeng,Xiangfei Guo
Tungsten powder is an essential raw material for producing tungsten carbide powders and tungsten-based alloys. However, the fabrication of high-performance spherical tungsten powders remains costly, and achieving a uniform distribution of doped elements poses significant challenges. In this study, a molecularly homogeneous W-Cr precursor solution was prepared using soluble salts, namely ammonium metatungstate ((NH 4 ) 6 [H 2 W 12 O 40 ]·xH 2 O)) and ammonium chromate ((NH 4 ) 2 CrO 4 ). Near-spherical W-Cr 2 O 3 composite powders with various Cr doping contents were synthesized through spray drying, calcination, and low-temperature hydrogen reduction. Subsequently, WC-10Co-xCr cemented carbides were fabricated via spark plasma sintering (SPS) following carburization. The effects of reduction temperature and Cr content on the morphology and phase composition of the W-Cr 2 O 3 composite powders were systematically examined. In addition, the influence of Cr doping on the mechanical properties of the cemented carbides was preliminarily evaluated. The results reveal that, at a reduction temperature of 900 °C and a Cr doping level of 0.5 wt%, the W-Cr 2 O 3 composite powders exhibit a uniform near-spherical morphology with fine and consistent particle sizes. The corresponding cemented carbide demonstrates superior overall performance. Furthermore, the Cr element is uniformly dispersed throughout the WO 3 precursor, W-Cr 2 O 3 composite powders, and the final alloy matrix.
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高影响因子
Desalination and Water Treatment
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2024
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IF 1
Tian Tian,Yannan Jia,Jianguo Wu,Jinlong Zhao,Kai Xu,Zijie Wang,Zheng Wang
With the increasing threat antimony (Sb) pollution poses to the environment, its removal from water is becoming increasingly important. Accordingly, metal-organic frameworks (MOFs) are garnering increasing research attention owing to their excellent performance as adsorbents. Here, the MOF MIL-101(Cr)-NH 2 was prepared directly by solvothermal synthesis. Sb(III) adsorption using MIL- 101(Cr)-NH 2 was evaluated systematically at varying adsorbent dosages and pHs. And the adsorption kinetics, isotherms, and thermodynamics were explored by altering the contact time, initial Sb(III) concentration, and temperature, respectively. The results revealed that Sb(III) was adsorbed onto MIL-101(Cr)-NH 2 very quickly, even at low antimony concentrations. The maximum Sb(III) adsorption capacity of MIL-101-NH 2 is 83.61 mg g -1 . In the presence of coexisting ion (NO 3 - ), the amount of Sb(III) adsorbed was slightly increased, which may be due to the formation of an inner-sphere complex. The Box–Behnken method was used to design and optimize a response surface with reference to three main influencing factors, that is, dosage, pH, and temperature, so as to obtain a multivariate quadratic model of adsorption behavior and identify the optimal adsorption conditions. Finally, a preliminary economic analysis of the synthetic material was carried out.
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高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2017
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IF 3.582
Lingwei Lu,Shuang Ni,Gang Liu,Xiaoxiang Xu
The crystal structure of a photocatalyst generally plays a pivotal role in its electronic structure and catalytic properties . In this work, we synthesized a series of La/Cr co-doped perovskite compounds ATiO 3 (M = Ca, Sr and Ba) via a hydrothermal method . Their optical properties and photocatalytic activities were systematically explored from the viewpoint of their dependence on structural variations, i.e. impact of bond length and bond angles. Our results show that although La/Cr co-doping helps to improve the visible light absorption and photocatalytic activity of these wide band gap semiconductors , their light absorbance and catalytic performance are strongly governed by the Ti O bond length and Ti O Ti bond angle. A long Ti O bond and deviation of Ti O Ti bond angle away from 180° deteriorate the visible light absorption and photocatalytic activity. The best photocatalytic activity belongs to Sr 0.9 La 0.1 Ti 0.9 Cr 0.1 O 3 with an average hydrogen production rate ∼2.88 μmol/h under visible light illumination (λ ≥ 400 nm), corresponding to apparent quantum efficiency ∼ 0.07%. This study highlights an effective way in tailoring the light absorption and photocatalytic properties of perovskite compounds by modifying cations in the A site.
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Journal of Energy Chemistry
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2026
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IF 15.6
Yunlong Wang,Xin Zhang,Kai Liu,Ziyu Ling,Mingzhe Li,Kepi Chen,Yuzhen Lv
Water splitting powered by intermittent renewable energy calls for efficient anode electrocatalysts to overcome both sluggish four-electron OER kinetics and poor durability under fluctuating conditions. Here, we synergistically engineer NiFeOOH with Ce doping and Cr vacancies through a facile one-step electrodeposition method. XPS, XAS and DFT results reveal that Ce doping elevates the Ni valence state to strengthen *OH adsorption, while Cr vacancies redistribute charge around Fe sites to weaken *OH binding. This complementary modulation reduces the Gibbs free energy of the rate-determining step for the OER and promotes the reaction pathway via dual-site synergistic catalysis. It achieves an ultralow overpotential of 280 ± 6.1 mV at 1 A cm −2 with a small Tafel slope of 33.5 mV dec −1 . Notably, the anode exhibits excellent stability under both steady-state (2000 h) and fluctuating (9000 cycles) operation, owing to the rapid charge buffering of the Ce 3+ /Ce 4+ redox couple and the flexible coordination environment arising from Cr vacancy-induced lattice relaxation. Their synergistic effect stabilizes Ni/Fe valence states and M–O bonds, thereby lowering charge consumption, enhancing Faradaic efficiencies and suppressing over-oxidation and deactivation. This study offers an effective route to design resilient anodes for efficient water oxidation under fluctuating power. The 600 cm 2 NiFeOOH catalyst co‑modified with Ce doping and Cr vacancies by electrodeposition, uses Ce 3+ /Ce 4+ redox and Cr vacancies to buffer charge and structure, synergistically stabilizing active sites and optimizing the OER pathway under fluctuating power. Download: Download high-res image (185KB) Download: Download full-size image
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高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2026
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IF 9.2
Ye He,Xiaoyang Wang,Yue Shen,Songju Luo,Zhaoqin Xu,Xiaojiang Mu,Lei Miao
As ammonia (NH 3 ) emerges as a pivotal renewable hydrogen carrier, the development of cost-effective and high-performance electrocatalysts for the ammonia oxidation reaction (AOR) is imperative for sustainable hydrogen production. However, non-noble-metal catalysts are frequently bottlenecked by sluggish kinetics, restricted active-site exposure, and severe intermediate poisoning. Herein, a hierarchical Cr 2 O 3 @CuO heterostructure was synthesized on nickel foam via a two-step hydrothermal method. The optimized nanocatalyst delivers a remarkable AOR activity, achieving 10 mA cm −2 at a low potential of 1.32 V vs. RHE, alongside exceptional durability for 36 h at a high current density of 150 mA cm −2 . Experimental and density functional theory (DFT) studies reveal that Cr incorporation enriches oxygen vacancies and downshifts the d-band center from −1.12 eV to −1.79 eV. Notably, the dynamic evolution of high-valent Cr 6+ species during AOR effectively attenuates intermediate adsorption, lowering the maximum dehydrogenation free-energy barrier from 2.06 to 0.96 eV. This study underscores the significance of dynamic valence regulation in enhancing AOR kinetics and provides a robust paradigm for the rational design of transition-metal-based catalysts for the ammonia-to-hydrogen economy.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2026
·
IF 12.5
Shiyin Zhao,Songyang Jiang,Yuxuan Xia,Fang Wang,Yujiao Li,Zhuoliang Liu,Xin Min,Cheng-an Tao
First piezo-responsive MOF heterostructure for mechanical Cr(VI) reduction. • F-modified MOF and ZnO loading synergistically boost piezoelectric response. • Efficient piezo-catalytic interface enables ultrafast Cr(VI) reduction. • 10 ppm Cr(VI) completely reduced to undetectable level within only 15 s. Hexavalent chromium (Cr(VI)) is highly toxic and carcinogenic; its reduction to Cr(III) remains the most viable remediation strategy. Piezoelectric catalysis, which converts mechanical energy into chemical energy via built-in electric fields, offers a sustainable route for pollutant degradation. However, the application of piezoelectric Metal-Organic Frameworks (MOFs) in heavy metal reduction remains largely unexplored. Herein, we report a strategy of fluorination combine with ZnO loading to construct piezoelectric MOF heterostructures for ultrafast Cr(VI) reduction. The optimized ZnO/UiO-66-F 4 completely reduced 10 ppm Cr(VI) to below detection limits within merely 30 s under sonication, substantially outperforming pristines. Systematic characterizations and DFT calculations revealed that fluorination depresses the conduction band to −0.91 V vs. NHE, establishing a type-II staggered band alignment with ZnO that synergizes with the piezoelectric field to drive vectorial charge separation, as corroborated by markedly reduced charge-transfer resistance and prolonged fluorescence lifetime with enhanced quantum yield. Mechanistic investigations further identified the interfacial Zn Zr dual-atom site as the true catalytic center, exhibiting the strongest Cr(VI) adsorption affinity and the lowest activation energy barrier for the rate-determining step. The catalyst demonstrated exceptional durability, retaining 98.2% removal efficiency after five cycles with negligible metal leaching. This work pioneers the application of piezoelectric MOFs in heavy metal remediation and establishes a molecular-level electronic modulation strategy for mechanical-energy-driven water purification. Piezoelectric ZnO/UiO-66-F 4 heterostructure was constructed via fluorine modification coupled with ZnO loading, demonstrating superior piezocatalytic performance for Cr(VI) reduction under ultrasonic vibration. Download: Download high-res image (138KB) Download: Download full-size image
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高影响因子
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
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2026
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IF 3.1
Afridi Muhammad Naveed,Adil Sawaira,Fatima Rida,Khan Fazal Maula,Ali Imran,Mir Irshad Ahmad,Miao Baoji,Lee Kang Hoon
Heavy metal contamination in industrial wastewater remains a critical global environmental concern. In this study, an Al/Mg/Zr-MOF (AMZ-MOF) was synthesized via a solvothermal method and systematically evaluated for Cr (VI) removal from aqueous solutions. Comparative analysis demonstrated that AMZ-MOF exhibited superior Cr (VI) removal efficiency relative to pristine Zr-MOF, Mg/Zr-MOF, and Al/Zr-MOF. The synthesized AMZ-MOF composite was subjected to comprehensive characterization using FESEM, TEM, XRD, BET, FTIR, and XPS analyses. The study systematically investigated the influence of key operational parameters, including contact time, temperature, pH, and initial Cr (VI) concentration, on the composite’s sorption behavior. AMZ-MOF demonstrated exceptional performance, achieving a maximum Cr (VI) sorption capacity of 185.2 mg/g. Remarkably, the sorbent exhibited rapid initial uptake kinetics, reaching adsorption equilibrium within 120 min. Mechanistic insight was gained through adsorption isotherm and kinetic modeling, revealing that the process is best described by the Langmuir isotherm and the Pseudo-Second-Order kinetic model, suggesting monolayer adsorption onto a heterogeneous surface and chemisorption as the rate-limiting step, respectively. Further FTIR and XPS analyses corroborated the proposed sorption mechanism, clarifying the key functional groups and surface interactions involved in Cr (VI) removal. The proposed adsorbent demonstrated excellent reusability over five adsorption–desorption cycles, underscoring its stability and practical potential for Cr (VI) remediation.
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高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
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2026
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IF 2.4
Dequan Ye,Wan Liu,Yi Tan,Luyi Niu,Dan Xie,Hongyu Chen,Jing Li,Ping Jiang
To remove hazardous Cr (VI) from wastewater, a novel 3D porous fluorescent cellulose-based hydrogel was synthesized to remove Cr (VI) from wastewater. It was created by loading carbon dots into cellulose micron fibers gel matrix via physical action and hydrogen bonds. The hydrogel’s morphology, crystalline structure, chemical composition, optical properties, sorption, and detection properties were analyzed. It exhibited good fluorescence properties with an absolute quantum yield of 15.94%. The hydrogel had a maximum adsorption capacity of 155.8 mg/g, with adsorption isotherms fitting the Langmuir model and kinetics fitting the pseudo-second-order model. It also showed selective and sensitive detection of Cr(VI) with a detection limit of 5 mg/L and an analytical linear range of 10–200 mg/L. FTIR and XPS analyses revealed that cellulose micron fibers improved adsorption ability, and carbon dots served as fluorescent probes for Cr(VI) detection. The material’s excellent mechanical properties, including a 180° anti-bending angle, 47.96% compression ratio, and 360° torsion angle, make it a candidate product that is both efficient for detection and capable of removing Cr(VI) from wastewater.
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高影响因子
DESALINATION
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2026
·
IF 9.9
Yu Qing,Yang Bao,Yuhao Pan
Cr/F co-doped LiMn 2 O 4 was compared with undoped, Cr-only and F-only spinel controls. • Co-doping raised 1C capacity to 124.6 mAh g −1 and HCDI Li + uptake to 35.07 mg g −1 . • The co-doped electrode kept 83% of its Li + uptake over 100 cycles with 1.4% Mn loss. • A reference-cell test traced most capacity fade to the carbon counter electrode. • Li + /Mg 2+ separation factor of 24.0 in untreated old brine with acid-free desorption. Spinel LiMn 2 O 4 (LMO) is a Li + -selective intercalation host for hybrid capacitive deionization (HCDI), but Jahn–Teller distortion and Mn dissolution limit its durability in Mg-rich brines. Here, Cr 3+ and F − were introduced at the nominal cationic and anionic sites of LMO to obtain LiCr 0.05 Mn 1.95 O 3.95 F 0.05 (CFLMO), and undoped, Cr-only (CrLMO) and F-only (FLMO) controls were prepared by the same route. XRD and FTIR showed that the average spinel framework was retained, and Cr 2p and F 1s XPS detected both added elements near the CFLMO surface. At 1C, CFLMO delivered a discharge capacity of 124.6 mAh g −1 (84% of the theoretical value), compared with 92.1 mAh g −1 for LMO. In HCDI tests with 32.74 mg L −1 Li + , CFLMO reached a salt adsorption capacity (SAC) of 35.07 mg g −1 at a charge efficiency of 0.89. After 100 adsorption–desorption cycles against an activated‑carbon (AC) counter electrode, CFLMO retained 83% of its initial SAC with a Mn dissolution ratio of 1.4%; replacing the AC electrode in an LMO||AC reference cell restored part of the lost adsorption response, identifying a counter-electrode contribution to cell-level capacity loss. In untreated Yiliping salt-lake old brine (Mg 2+ /Li + mass ratio 36.1), three CFLMO electrodes recovered 37.5 ± 1.5 mg g −1 Li + with a Li + /Mg 2+ separation factor of 24.0 ± 2.7, and desorption into pure water lowered the Mg 2+ /Li + mass ratio to 1.52 ± 0.18. The matched-control and real-brine results support Cr/F-modified LMO as a candidate for selective lithium recovery from Mg-rich salt-lake brines.
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高影响因子
Journal of Environmental Chemical Engineering
·
2026
·Vol. 14
·期 6
·125040
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IF 7.5
Xiuxiu Wu,Jingling Zhang,Min Yuan,Hui Cao,Liling Hao,Tai Ye,Jinsong Yu,Zhu Liu,Fei Xu
Adsorption prediction models of heavy metal IIPs by machine learning algorithms were constructed. • Multivariate feature engineering was applied according to structure-performance relationship. • The reliability of the prediction model was confirmed by experimental evaluation of prepared IIPs. • This study provided a data-driven model and profound mechanistic insights for rational design of IIPs. Ion-imprinted polymers (IIPs) are recognized as excellent adsorbents for heavy metal detection and removal to enable environmental safety. However, traditional trial-and-error development method for high performance IIPs is time-consuming, labor-intensive and costly. In this work, data-driven adsorptive removal rate prediction models were constructed which offers a promising alternative by facilitating rational design of IIPs structure and precise regulation of their adsorption performance. Specifically, multivariate feature engineering was performed to applied machine learning algorithms (Gaussian process regression, generalized regression neural network, least squares boosting, extreme gradient boosting, convolutional neural network, and multilayer perceptron regression) according to structure-adsorption performance relationships. Models were optimized via sparrow search algorithm, and their prediction performances were compared. Among them, extreme gradient boosting exhibited superior prediction accuracy and generalization, achieving correlation coefficient R 2 of 0.93 on training and testing sets, with RMSE and MAE low to 7.03 and 5.64, respectively. SHAP analysis revealed pH as the dominant influencing factor. Guided by this prediction model, novel Cr(VI) IIPs were designed and used for Cr(VI) adsorption from industrial wastewater with a removal efficiency of 72.75%-83.61%. The strong correlation (R 2 =0.79) between predicted and experimentally validated removal efficiency confirms the model's reliability and practical utility. This study not only provides novel high-performance IIPs for Cr(VI) adsorptive removal from environment, but also offers a reliable data-driven rational design strategy for functional materials development that can be used to ensure environmental safety. Download: Download high-res image (213KB) Download: Download full-size image
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Journal of Environmental Chemical Engineering
·
2026
·Vol. 14
·期 6
·125079
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IF 7.5
Xiaohui Sun,Fangmin Yan,Zijun Ye,Benyi Cao,Fei Wang
A chemical regeneration strategy was developed for deactivated BC-nZVI. • Reactivity recovery was governed by three synergistic mechanisms. • Citric acid exposed reactive iron cores via ligand-mediated crust dissolution. • Ascorbic acid sustained long-term reactivity through surface-mediated reduction. The passivation and clogging of reactive media critically limit the long-term efficacy of zero-valent iron (ZVI)-based permeable reactive barriers (PRBs) for in-situ groundwater remediation. To overcome this limitation, this study proposes a novel in-situ regeneration method employing a citric acid (CA) and ascorbic acid (AA) to restore the Cr(VI) removal capacity of a deactivated biochar-supported nanoscale ZVI (BC-nZVI) PRB. Results show that the optimal regeneration efficiency was achieved with a 2.5 g/L regenerant concentration for 1 h, yielding regeneration rates of 101.7% for citric acid (CA) and 79.7% for ascorbic acid (AA), respectively. After regeneration, the BC-nZVI exhibits enhanced pH tolerance for Cr(VI) removal compared to the pristine BC-nZVI. Notably, AA-treated systems demonstrate superior recyclability, maintaining high removal efficiency over multiple cycles, whereas CA-treated systems show only moderate regeneration performance. Mechanistically, CA provides rapid initial kinetics by promoting the dissolution of the iron passivation layer through complexation, while AA favors a solid-surface reduction pathway that better preserves material stability. Moreover, the regeneration process can effectively control the mobility of chromium, and through the combined actions of reduction, complexation, and co-precipitation, Cr(III) in the aqueous phase can be ultimately restored to baseline levels.This work provides a viable, low-cost, and environmentally friendly strategy to drastically prolong PRB lifespan, circumventing the need for expensive media replacement and offering a sustainable solution for long-term site remediation. Download: Download high-res image (211KB) Download: Download full-size image
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Journal of Environmental Chemical Engineering
·
2026
·Vol. 14
·期 5
·125223
·
IF 7.5
Haowen Zou,Neng Lv,Zihui Zhang,Jingfu Liu,Qikai Chen,Lei Dong,Hongkun Luo,Shicai Luo,Yaoyue Zhang,Ping Wang,Zhongkuan Wu,Haixiang Cheng,Feng He
SA-mZVI bm showed 22-fold faster Cr(VI) removal and 17-fold higher capacity. • Sustained electron transfer and inhibited passivation boost ES by 2-fold. • SA-mZVI bm maintained high performance in real waters, showing practical potential. Zero-valent iron (ZVI) is broadly applied in the remediation of toxic, carcinogenic, and highly mobile Cr(VI), but its inherent reactivity is drastically diminished due to rapid surface passivation during the reaction process. Herein, microscale ZVI (mZVI) was modified with inorganic acid sulfamic acid (SA) via ball-milling to fabricate SA-mZVI bm , and its Cr(VI) removal performance, reaction mechanism, and practical applicability were systematically investigated. Results showed that SA modification reshaped the surface oxide layer of mZVI, facilitating the formation of conductive Fe 3 O 4 and introducing sulfonic acid groups to enhance surface complexation capability. At an initial pH 5 and a dosage of 0.5 g/L, SA-mZVI bm achieved a Cr(VI) removal rate 22 times that of unmodified mZVI bm within the first 5 min, with a surface area-normalized removal capacity approximately 17 times greater over 5 h. Mechanistic studies revealed that SA corrosion restructured the oxide layer to boost Fe(II) generation. DFT calculations suggested that the SA-modified ZVI surface provided more accessible sites for Cr(VI) adsorption in a bidentate binuclear configuration (adsorption energy: −5.9 eV), shortening the Fe-Cr bond distance to 3.6 Å and accelerating electron transfer. Additionally, SA modification significantly improved the electron selectivity (88.4% vs 45.7%) and ZVI utilization efficiency (5.8% vs 0.2%), effectively alleviating surface passivation, while 94.6% of Fe 0 remained unused. SA-mZVI bm also demonstrated superior Cr(VI) removal performance in real water matrices and electroplating wastewater. This study provides new insights and theoretical guidance for developing efficient and stable inorganic acid-modified ZVI materials. Download: Download high-res image (190KB) Download: Download full-size image
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危险品化学品经营许可证（带存储）