JOURNAL OF RARE EARTHS
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2017
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IF 2.429
Dongri WANG,Yongqing ZHAO,Shiyong YU
A series of cerium sulfides were successfully prepared using commercially available nanoscale CeO 2 as precursor, anhydrous Na 2 CO 3 as dopants, CS 2 as sulfur source, under 600–800 °C, respectively. Properties of samples were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and spectrophotometry. The results showed that corresponding γ-Ce 2 S 3 with small size was obtained by using nanoscale CeO 2 as precursor; pure phase γ-Ce 2 S 3 could be obtained under low temperature of 700 °C. Coloring properties of γ-Ce 2 S 3 obtained under 800 °C were studied by researching γ-Ce 2 S 3 /PE and γ-Ce 2 S 3 /PVC composites, respectively. The results showed that satisfied coloring effects to PE and PVC were obtained by using 0.5 phr and 0.2 phr γ-Ce 2 S 3 , respectively.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
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2025
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IF 7.3
Ning Li,Linzi Zuo,Fanchao Xu,Xiaolei Qu,Heyun Fu,Huiting Liu
Cerium sulfide (Ce 2 S 3 ) pigment is an environmentally friendly novel inorganic red-colored metal pigment, representing a potential alternative to traditional heavy metal pigments. In this study, we report concurrent re-precipitation and photo-dissolution of cerium sulfide pigment in a sunlit aquatic phase. Commercial cerium sulfide pigment transforms into its re-precipitation product, CeCO 3 OH, along with the generation of H 2 S gas in its re-precipitation process. Simultaneously, cerium sulfide pigment photo-dissolution results in a significant release of Ce ions. After 4 hours of simulated sunlight irradiation, the particle size of cerium sulfide pigment significantly reduces, and 10.4% of elemental Ce is released into the solution as free Ce ions. The key photo-dissolution mechanism is the oxidation reaction between photogenerated holes and the crystal lattice of the pigment. Cerium sulfide pigment and its re-precipitation product, CeCO 3 OH, can be excited by specific wavelengths in the solar spectrum, mediating the pigment photo-dissolution. UV light shielding can inhibit the cerium sulfide pigment photo-dissolution. Superoxide and hydroxyl radicals are generated during the photoreaction process, in which the hydroxyl radical may oxidize the photo-induced released Ce(III) to Ce(IV) and the re-precipitation-generated H 2 S to SO 4 2- . Our research indicates that commercial cerium sulfide pigment undergoes a series of transformation processes in aquatic environments, potentially posing certain environmental risks.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2023
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IF 11.4
Fengping Zhou,Ye Xiao,Meina Guo,Shizhong Wang,Rongliang Qiu,Jean-Louis Morel,Marie-Odile Simonnot,Wei-Xian Zhang,Weihua Zhang,Ye-Tao Tang
To cope with the urgent and unprecedented demands for rare earth elements (REEs) in sophisticated industries, increased attention has been paid to REE recovery from recycled streams. However, the similar geochemical behaviors of REEs and transition metals often result in poor separation performance due to nonselectivity. Here, a unique approach based on the selective transformation between ceria sulfation and iron/manganese mineralization was proposed, leading to the enhancement of the selective separation of REEs. The mechanism of the selective transformation of minerals could be ascribed to the distinct geochemical and metallurgical properties of ions, resulting in different combinations of cations and anions. According to hard-soft acid-base (HSAB) theory, the strong Lewis acid of Ce(III) was inclined to combine with the hard base of sulfates (SO42–), while the borderline acid of Fe(II)/Mn(II) prefers to interact with oxygen ions (O2-). Both in situ characterization and density functional theory (DFT) calculation further revealed that such selective transformation might trigger by the generation of an oxygen vacancy on the surface of CeO2, leading to the formation of Ce2(SO4)3 and Fe/Mn spinel. Although the electron density difference of the configurations (CeO2–x-SO4, Fe2O3–x-SO4, and MnO2–x-SO4) shared a similar direction of the electron transfer from the metals to the sulfate-based oxygen, the higher electron depletion of Ce (QCe = −1.91 e) than Fe (QFe = −1.66 e) and Mn (QMn = −1.64 e) indicated the higher stability in the Ce–O–S complex, resulting in the larger adsorption energy of CeO2–x-SO4 (−6.88 eV) compared with Fe2O3–x-SO4 (−3.10 eV) and MnO2–x-SO4 (−2.49 eV). This research provided new insights into the selective transformation of REEs and transition metals in pyrometallurgy and thus offered a new approach for the selective recovery of REEs from secondary resources.
研究领域:
冶金学
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材料科学
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
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2023
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IF 5.2
Hongbin Zhang,Gongxun Bai,Le Wang,Muzhi Cai,Renguang Ye,Junjie Zhang,Shiqing Xu
Red non-toxic and environmentally friendly γ -phase cerium sulfide powders have promising applications in the fields of coatings, outdoor displays and smart buildings. However, the development of an environmentally friendly preparation process and the improvement of production efficiency of cerium sulfide powders remain major challenges. In this study, eco-friendly γ -Ce 2 S 3 powders with excellent color properties have been produced by adding ammonium thiocyanate to the precursor of cerium without H 2 S or CS 2 . The effect of impurities (mainly Ce 2 O 2 S) with different amounts on spectral properties of cerium sulfide powders has been studied through chemical and physical methods. In addition, the significance of impurity doping on the reaction synthesis was studied by combining detailed experimental characteristics with density functional theory calculations. The results show that the reduction of impurity content can greatly improve the chromaticity value of γ -Ce 2 S 3 and change color from dark red to bright red.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
LANGMUIR
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2025
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IF 3.9
Zhengquan Jiang,Zhengguang Wang,Chuanwei Qiao,Yadong Wang,Shengmao Zhang,Yujuan Zhang,Ruizhu Zhang,Weihua Li
With the rapid development of modern industry, traditional lubricants often require a variety of additives to be used in conjunction with each other, which not only increases the cost but also causes a waste of resources. Therefore, the development of a lubricant additive with both a dyeing function and an antiwear and friction reduction performance can more effectively meet the industrial needs. Cerium sulfide (Ce2S3), with its excellent photostability, weather resistance, thermal stability, and nontoxicity, shows great potential as an environmentally friendly pigment. However, traditional methods for synthesizing Ce2S3 are typically hindered by high-temperature requirements and potential toxicity issues, which limits the broad application of Ce2S3 in lubricants. To overcome these limitations, this study employed a liquid-phase method under mild conditions to synthesize oleylamine-modified, wrinkle-free Ce2S3 nanosheets (OA-Ce2S3 NSs). The antiwear and friction-reducing properties of OA-Ce2S3 NSs in poly alpha-olefin-6 base oils were evaluated under various friction conditions with a four-ball tribometer. Experimental results indicate that OA-Ce2S3 NSs significantly enhance the friction-reducing and antiwear performance of lubricants by forming a physical adsorption film and an ultra thick tribochemical reaction film (with a typical thickness of 350 nm and a maximum thickness of up to 700 nm) on the friction surface. Furthermore, the study elucidates the lubrication mechanism of OA-Ce2S3 NSs and proposes their sliding mechanism on friction surfaces. This research highlights the potential of Ce2S3 nanosheets as lubricant additives and provides future directions for optimizing their synthesis and multifunctional applications, offering new insights into the field of lubrication science.
研究领域:
材料科学
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润滑工程
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纳米技术
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产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2025
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IF 6.9
Jingzhi Hou,Hongyan Zhang,Chu Chen,Chen Yang,Haiyang Zhang,Zhipeng Li
In this study, a high-performance ammonia (NH 3 ) gas sensor based on a CeO 2 /CdS heterojunction with increased surface defects was prepared using the hydrothermal method. First-principles calculations based on density functional theory (DFT) were employed to elucidate the sensing mechanism. Experimental results indicate that more surface defects and surface hydroxyl groups can effectively enhance the performance of the CeO 2 /CdS NH 3 gas sensor at room temperature. The response value of CeO 2 /CdS is 739.5 at a concentration of 500 ppm NH 3 , and the response/recovery time at 50 ppm is 1.27 s/1.63 s, which is faster compared with the previously reported NH 3 gas sensors based on CeO 2 . Theoretical calculations suggest that the presence of more oxygen vacancies or sulfur vacancies on the surface of CeO 2 or CdS can lead to the generation of additional d electrons and the capture of more NH 3 molecules. Furthermore, it was discovered for the first time that the d-band center of CeO 2 could shift upward under more surface oxygen vacancies and hydroxyl groups, which can improve the chemical activity of the CeO 2 /CdS and enhance its adsorption capacity for NH 3 molecules. This research constructed CeO 2 /CdS with multiple surface defects through a heterogeneous structure, providing new ideas for developing high-performance NH 3 gas sensors.
研究领域:
材料科学
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传感器技术
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表面化学
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纳米材料
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气体传感
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）