Yoshiki Kiyota, Seiji Ono, Dr. Kaito Sasaki, Nanako Tamai, Hironori Sugimoto, Prof. Dr. Yosuke Okamura, Prof. Dr. Shinichi Koguchi, Prof. Dr. Masashi Higuchi, Prof. Dr. Yu Nagase, Prof. Dr. Naoki Shinyashiki, Prof. Dr. Sayaka Uchida, Prof. Dr. Takeru Ito
Highly conductive inorganic-organic hybrid crystals were constructed by using polyoxovanadate cluster and ionic-liquid cation. Two types of hybrid crystals containing alkaline earth metal (divalent) cations were obtained. Conductivities under a humidified condition reached 3.3×10–3 S cm–1 at 353 K (80 °C). More information can be found in the Research Article by Takeru Ito and co-workers.
利用聚氧乙烯钒酸盐簇和离子液体阳离子构建了高导电性无机-有机杂化晶体。获得了两种含有碱土金属（二价）阳离子的杂化晶体。在 353 K (80 °C) 的湿润条件下，电导率达到 3.3×10-3 S cm-1。更多信息，请参阅伊藤 Takeru 及其合作者的研究文章。
{"title":"Front Cover: Inorganic-Organic Hybrid Crystals Derived from Polyoxovanadate and Ionic-Liquid toward Promising Conductive Materials (ChemNanoMat 8/2024)","authors":"Yoshiki Kiyota, Seiji Ono, Dr. Kaito Sasaki, Nanako Tamai, Hironori Sugimoto, Prof. Dr. Yosuke Okamura, Prof. Dr. Shinichi Koguchi, Prof. Dr. Masashi Higuchi, Prof. Dr. Yu Nagase, Prof. Dr. Naoki Shinyashiki, Prof. Dr. Sayaka Uchida, Prof. Dr. Takeru Ito","doi":"10.1002/cnma.202480801","DOIUrl":"10.1002/cnma.202480801","url":null,"abstract":"<p>Highly conductive inorganic-organic hybrid crystals were constructed by using polyoxovanadate cluster and ionic-liquid cation. Two types of hybrid crystals containing alkaline earth metal (divalent) cations were obtained. Conductivities under a humidified condition reached 3.3×10<sup>–3</sup> S cm<sup>–1</sup> at 353 K (80 °C). More information can be found in the Research Article by Takeru Ito and co-workers.<figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":2.6,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cnma.202480801","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Erik Dubai, Qingyang Wu, Stefan Lauterbach, Jan P. Hofmann, Marcus Einert
NiCo2O4 has been proven to show high electrocatalytic activity, however facile and inexpensive techniques for preparation of this compound as mesostructured thin film is lacking. In this study, the sol‐gel synthesis of nanocrystalline mesoporous spinel NiCo2O4 thin films by dip‐coating and soft‐templating using the evaporation‐induced self‐assembly approach is reported. The morphology and crystallographic structure were thoroughly probed by various physicochemical characterization techniques collectively validating the development of uniform mesoporous NiCo2O4 architectures crystallizing exclusively in the cubic spinel phase after calcination in air. The surface area of the thin films depended on the calcination temperature. XPS investigations showed that the amount of Ni3+ and defective oxygen species increased for decreasing calcination temperatures. The overall electrochemical surface area, Ni3+ content, charge transfer resistance, and amount of defective oxygen sites were found to collectively control the oxygen evolution reaction performance. After an optimized annealing procedure at 300°C and chronopotentiometric analysis at 10 mA/cm2 for 1.5 h, a low overpotential of 330 mV vs. RHE at 10 mA/cm2 in alkaline solution was achieved. The results highlight the necessity of precise selection of the appropriate calcination temperature and electrochemical pre‐treatment conditions for adjusting the concentration of electrocatalytically active reaction sites of sol‐gel‐derived NiCo2O4 thin films.
{"title":"Surface Defects, Ni3+ Species, Charge Transfer Resistance, and Surface Area dictate the Oxygen Evolution Reaction Activity of Mesoporous NiCo2O4 Thin Films","authors":"Erik Dubai, Qingyang Wu, Stefan Lauterbach, Jan P. Hofmann, Marcus Einert","doi":"10.1002/cnma.202400242","DOIUrl":"https://doi.org/10.1002/cnma.202400242","url":null,"abstract":"NiCo2O4 has been proven to show high electrocatalytic activity, however facile and inexpensive techniques for preparation of this compound as mesostructured thin film is lacking. In this study, the sol‐gel synthesis of nanocrystalline mesoporous spinel NiCo2O4 thin films by dip‐coating and soft‐templating using the evaporation‐induced self‐assembly approach is reported. The morphology and crystallographic structure were thoroughly probed by various physicochemical characterization techniques collectively validating the development of uniform mesoporous NiCo2O4 architectures crystallizing exclusively in the cubic spinel phase after calcination in air. The surface area of the thin films depended on the calcination temperature. XPS investigations showed that the amount of Ni3+ and defective oxygen species increased for decreasing calcination temperatures. The overall electrochemical surface area, Ni3+ content, charge transfer resistance, and amount of defective oxygen sites were found to collectively control the oxygen evolution reaction performance. After an optimized annealing procedure at 300°C and chronopotentiometric analysis at 10 mA/cm2 for 1.5 h, a low overpotential of 330 mV vs. RHE at 10 mA/cm2 in alkaline solution was achieved. The results highlight the necessity of precise selection of the appropriate calcination temperature and electrochemical pre‐treatment conditions for adjusting the concentration of electrocatalytically active reaction sites of sol‐gel‐derived NiCo2O4 thin films.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhang Rui, Yan Guo, Xiaoyu Zhu, Maoyan Dou, Tao Tao, Hui He, Ziqin Gong
RuO2/Cysteine (RuO2/Cys) nanocomposites were synthesized using a facile high‐temperature hydrothermal method, with improved specific capacitance and good electrochemical durability. The advantage of using cysteine is that its molecule is rich in ligands such as carboxyl, sulfhydryl, and amino groups, which can be easily bound to hydrated RuO2, thus facilitating its effective dispersion. Analyses of its morphology, structure, and chemical composition showed that the incorporation of L‐cysteine greatly inhibited the agglomeration of RuO2 and improved its dispersion, and the scale of RuO2 was reduced from the original micrometer scale to the nanometer scale. Such structures facilitated proton transfer and electron transfer, so RuO2/Cys nanocomposites showed significantly improved specific capacitance, up to 1221.7 F g‐1, and the energy density was up to 108.6 Wh kg‐1 with a power density of 400.2 W kg‐1 at 1 A g‐1 in a 0.5 M H2SO4 electrolyte. The combination of L‐cysteine with RuO2 also effectively prevented the deformation of RuO2 in the redox process, and the capacitance retention rate was increased to 87.7% compared to 48.8% of pristine RuO2 after 10,000 charging‐discharging cycles. High capacitance performance and improved cyclic stability enable RuO2/Cys nanocomposite a favorable electrode material for wide applications in energy storage.
采用简便的高温水热法合成了 RuO2/半胱氨酸（RuO2/Cys）纳米复合材料，其比电容得到改善，电化学耐久性良好。使用半胱氨酸的优势在于其分子中富含羧基、巯基和氨基等配体，这些配体很容易与水合 RuO2 结合，从而促进其有效分散。对其形态、结构和化学成分的分析表明，L-半胱氨酸的加入大大抑制了 RuO2 的团聚，改善了其分散性，RuO2 的尺度也从原来的微米级缩小到纳米级。这种结构有利于质子转移和电子转移，因此 RuO2/Cys 纳米复合材料的比电容显著提高，高达 1221.7 F g-1，能量密度高达 108.6 Wh kg-1，在 0.5 M H2SO4 电解液中 1 A g-1 的功率密度为 400.2 W kg-1。L-cysteine 与 RuO2 的结合还有效防止了 RuO2 在氧化还原过程中的变形，与原始 RuO2 的 48.8% 相比，经过 10,000 次充放电循环后，电容保持率提高到 87.7%。高电容性能和更好的循环稳定性使 RuO2/Cys 纳米复合材料成为一种有利的电极材料，可广泛应用于储能领域。
{"title":"RuO2/Cysteine Nanocomposites for High‐Performance Supercapacitors","authors":"Zhang Rui, Yan Guo, Xiaoyu Zhu, Maoyan Dou, Tao Tao, Hui He, Ziqin Gong","doi":"10.1002/cnma.202400283","DOIUrl":"https://doi.org/10.1002/cnma.202400283","url":null,"abstract":"RuO2/Cysteine (RuO2/Cys) nanocomposites were synthesized using a facile high‐temperature hydrothermal method, with improved specific capacitance and good electrochemical durability. The advantage of using cysteine is that its molecule is rich in ligands such as carboxyl, sulfhydryl, and amino groups, which can be easily bound to hydrated RuO2, thus facilitating its effective dispersion. Analyses of its morphology, structure, and chemical composition showed that the incorporation of L‐cysteine greatly inhibited the agglomeration of RuO2 and improved its dispersion, and the scale of RuO2 was reduced from the original micrometer scale to the nanometer scale. Such structures facilitated proton transfer and electron transfer, so RuO2/Cys nanocomposites showed significantly improved specific capacitance, up to 1221.7 F g‐1, and the energy density was up to 108.6 Wh kg‐1 with a power density of 400.2 W kg‐1 at 1 A g‐1 in a 0.5 M H2SO4 electrolyte. The combination of L‐cysteine with RuO2 also effectively prevented the deformation of RuO2 in the redox process, and the capacitance retention rate was increased to 87.7% compared to 48.8% of pristine RuO2 after 10,000 charging‐discharging cycles. High capacitance performance and improved cyclic stability enable RuO2/Cys nanocomposite a favorable electrode material for wide applications in energy storage.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Irina G. Fomina, Inna O. Gozhikova, Natalia A. Sipyagina, Elena A. Straumal, Gennady P. Kopitsa, Andrey A. Mazilkin, Andrei A. Eliseev, Nikolay N. Efimov, Yury S. Zavorotny, Alexander V. Shvidchenko, Alexander Ya. Vul’, Igor L. Eremenko, Sergey A. Lermontov
A first composite material containing uniformly dispersed disaggregated detonation nanocrystalline diamonds (DNDs) in SiO2 aerogel matrix was prepared. The synthetic protocol included hydrolysis of tetramethyl orthosilicate (Si(OMe)4, TMOS) by hydrosol of surface carboxylated DNDs with a typical size of 4‐5 nm with DMSO serving as a cosolvent and a stabilizer of DND single crystals. Composite samples containing DNDs in silica aerogel matrix in concentration 1.0, 0.1 and 0.01% w/w were prepared at ambient temperature. HRTEM data revealed that DNDs nanocrystals were uniformly distributed in aerogel and did not form aggregates. Textural and optical composites’ properties were determined.
{"title":"First Example of Single‐Crystal Nanodiamonds Immobilized in Porous SiO2‐Aerogel Matrix: Synthesis and Characterization","authors":"Irina G. Fomina, Inna O. Gozhikova, Natalia A. Sipyagina, Elena A. Straumal, Gennady P. Kopitsa, Andrey A. Mazilkin, Andrei A. Eliseev, Nikolay N. Efimov, Yury S. Zavorotny, Alexander V. Shvidchenko, Alexander Ya. Vul’, Igor L. Eremenko, Sergey A. Lermontov","doi":"10.1002/cnma.202400172","DOIUrl":"https://doi.org/10.1002/cnma.202400172","url":null,"abstract":"A first composite material containing uniformly dispersed disaggregated detonation nanocrystalline diamonds (DNDs) in SiO2 aerogel matrix was prepared. The synthetic protocol included hydrolysis of tetramethyl orthosilicate (Si(OMe)4, TMOS) by hydrosol of surface carboxylated DNDs with a typical size of 4‐5 nm with DMSO serving as a cosolvent and a stabilizer of DND single crystals. Composite samples containing DNDs in silica aerogel matrix in concentration 1.0, 0.1 and 0.01% w/w were prepared at ambient temperature. HRTEM data revealed that DNDs nanocrystals were uniformly distributed in aerogel and did not form aggregates. Textural and optical composites’ properties were determined.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141929846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arun Kumar, Atif Suhail, Prem Sagar Shukla, Monojit Bag
In the pursuit of efficient optoelectronics devices, hybrid lead halide perovskite quantum dots (PQDs) have emerged as highly promising semiconductor materials due to their intriguing properties. While these materials have been used in many applications, the fundamental understanding of their behavior remains relatively unexplored, especially for the mixed halide perovskite samples. To facilitate the advancement of PQD technologies for commercial applications, it is essential to gain insights into the role of ion migration. This study delves into the fundamental aspects of ion migration in halide perovskite nanocrystals. Porous electrodes for supercapacitor application were fabricated using CsPbBr3-xIx (x=0,1,2) nanocrystals prepared via the ligand-assisted re-precipitation (LARP) method. Three-electrode electrochemical measurements and several other characterizations were conducted under dark conditions to evaluate device performance and elucidate the impact of mixed halides on device kinetics and stability. X-ray photoelectron spectroscopy before and after the electrochemical measurement reveals intriguing findings. Notably, the analysis uncovered the phase segregation in the metal halide perovskite nanocrystals with particular emphasis on CsPbBr2I due to its distinctive mixed-halide behavior. The specific capacitance increases with the increasing cycles. Interestingly, as the iodide content increases, there is no selective halide expulsion as the structure collapses rapidly.
在追求高效光电器件的过程中，混合卤化物铅包晶量子点（PQDs）因其引人入胜的特性而成为极具潜力的半导体材料。虽然这些材料已被广泛应用，但人们对其行为的基本认识仍相对欠缺，尤其是对混合卤化物包晶样品的认识。为了促进 PQD 技术在商业应用中的发展，深入了解离子迁移的作用至关重要。本研究深入探讨了卤化物包晶纳米晶体中离子迁移的基本问题。使用配体辅助再沉淀（LARP）法制备的 CsPbBr3-xIx （x=0,1,2）纳米晶体制作了用于超级电容器的多孔电极。在黑暗条件下进行了三电极电化学测量和其他一些表征，以评估器件性能并阐明混合卤化物对器件动力学和稳定性的影响。电化学测量前后的 X 射线光电子能谱分析揭示了令人感兴趣的发现。值得注意的是，该分析揭示了金属卤化物包晶纳米晶体中的相分离现象，特别强调了 CsPbBr2I，因为它具有独特的混合卤化物行为。比电容随着循环次数的增加而增加。有趣的是，随着碘化物含量的增加，由于结构迅速坍塌，因此没有选择性的卤化物排出。
{"title":"Structural Stability of Mixed-Halide Perovskite Nanocrystals in Energy Storage: The Role of Iodine Expulsion","authors":"Arun Kumar, Atif Suhail, Prem Sagar Shukla, Monojit Bag","doi":"10.1002/cnma.202400401","DOIUrl":"https://doi.org/10.1002/cnma.202400401","url":null,"abstract":"In the pursuit of efficient optoelectronics devices, hybrid lead halide perovskite quantum dots (PQDs) have emerged as highly promising semiconductor materials due to their intriguing properties. While these materials have been used in many applications, the fundamental understanding of their behavior remains relatively unexplored, especially for the mixed halide perovskite samples. To facilitate the advancement of PQD technologies for commercial applications, it is essential to gain insights into the role of ion migration. This study delves into the fundamental aspects of ion migration in halide perovskite nanocrystals. Porous electrodes for supercapacitor application were fabricated using CsPbBr3-xIx (x=0,1,2) nanocrystals prepared via the ligand-assisted re-precipitation (LARP) method. Three-electrode electrochemical measurements and several other characterizations were conducted under dark conditions to evaluate device performance and elucidate the impact of mixed halides on device kinetics and stability. X-ray photoelectron spectroscopy before and after the electrochemical measurement reveals intriguing findings. Notably, the analysis uncovered the phase segregation in the metal halide perovskite nanocrystals with particular emphasis on CsPbBr2I due to its distinctive mixed-halide behavior. The specific capacitance increases with the increasing cycles. Interestingly, as the iodide content increases, there is no selective halide expulsion as the structure collapses rapidly.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141884556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The unrelenting expansion of electronics and wireless communications has brought an onslaught of electromagnetic interference and environmental radiation as a new form of pollution. Filamentous aerogels offer a viable solution to this growing challenge: with their hierarchical inter‐ and intra‐filament porosities, they have recently shown great promise as EMI shielding materials. The multidirectional EM wave scattering within their hierarchical porous structure enhances attenuation much higher than conventional monolithic aerogels. This concept paper summarizes recent groundbreaking efforts in filamentous aerogel fabrication, with a focus on liquid streaming and 3D printing approaches. Further research and development could see filamentous aerogels emerge as next‐generation materials to combat the intensification of electromagnetic environmental impacts.
{"title":"Filamentous Aerogels for Electromagnetic Shielding","authors":"Zahra Rezaei, Elisabeth Prince, Milad Kamkar","doi":"10.1002/cnma.202400113","DOIUrl":"https://doi.org/10.1002/cnma.202400113","url":null,"abstract":"The unrelenting expansion of electronics and wireless communications has brought an onslaught of electromagnetic interference and environmental radiation as a new form of pollution. Filamentous aerogels offer a viable solution to this growing challenge: with their hierarchical inter‐ and intra‐filament porosities, they have recently shown great promise as EMI shielding materials. The multidirectional EM wave scattering within their hierarchical porous structure enhances attenuation much higher than conventional monolithic aerogels. This concept paper summarizes recent groundbreaking efforts in filamentous aerogel fabrication, with a focus on liquid streaming and 3D printing approaches. Further research and development could see filamentous aerogels emerge as next‐generation materials to combat the intensification of electromagnetic environmental impacts.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141884554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Protity Saha, Md. Abdul Aziz, Md. Mominul Islam, A. J. Saleh Ahammad
Seeking to establish a novel, eco‐friendly and ultra‐ sensitive electrochemical nitrite sensor, we have fabricated fluorine doped tin oxide (FTO) electrode with green synthesized gold nanoparticles (AuNPs) from gold salt and taro plant (Colocasia esculenta) extract (Taro_AuNPs/FTO). Different morphological and elemental analysis were conducted to undermine morphological condition and shapes of AuNPs. Further, electrochemical studies were performed for enabling observation on the modification as well as interaction between nitrite ion and AuNPs on the modified FTO. Furthermore, the performance of Taro_AuNPs/FTO sensor was evaluated using DPV technique and the limit of detection (LOD) was 0.923 nmol L‐1 (S/N=3) having sensitivity of 0.00503 μA mM−1 cm−2 within 5‐500 µmol L‐1. Additionally, an insightful mechanistic overview was highlighted about interacting nitrite on the modified electrode surface. Finally, interference test, stability, reproducibility and real sample analysis were conducted to establish the effectiveness of Taro_AuNPs/FTO electrochemical senor for environmental application.
{"title":"An Ultra‐sensitive Electrochemical Sensor for Nitrite Based on Green Synthesized Gold Nanoparticles Using Colocasia esculenta Extract","authors":"Protity Saha, Md. Abdul Aziz, Md. Mominul Islam, A. J. Saleh Ahammad","doi":"10.1002/cnma.202400325","DOIUrl":"https://doi.org/10.1002/cnma.202400325","url":null,"abstract":"Seeking to establish a novel, eco‐friendly and ultra‐ sensitive electrochemical nitrite sensor, we have fabricated fluorine doped tin oxide (FTO) electrode with green synthesized gold nanoparticles (AuNPs) from gold salt and taro plant (Colocasia esculenta) extract (Taro_AuNPs/FTO). Different morphological and elemental analysis were conducted to undermine morphological condition and shapes of AuNPs. Further, electrochemical studies were performed for enabling observation on the modification as well as interaction between nitrite ion and AuNPs on the modified FTO. Furthermore, the performance of Taro_AuNPs/FTO sensor was evaluated using DPV technique and the limit of detection (LOD) was 0.923 nmol L‐1 (S/N=3) having sensitivity of 0.00503 μA mM−1 cm−2 within 5‐500 µmol L‐1. Additionally, an insightful mechanistic overview was highlighted about interacting nitrite on the modified electrode surface. Finally, interference test, stability, reproducibility and real sample analysis were conducted to establish the effectiveness of Taro_AuNPs/FTO electrochemical senor for environmental application.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141884558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kishore Kandasamy, Yue Yu, Muhammad Waqas Iqbal, Luis Ricardez-Sandoval, Aiping Yu, David Simakov
Copper‐doped ceria (CuCeO2) catalysts with 0‐26.5 Cu/(Cu+Ce) at% were synthesized via the reverse microemulsion method. X‐ray diffraction analysis of freshly synthesized and spent (post‐reaction) catalysts showed no separate phase of copper of copper oxide, indicating that Cu was incorporated into the CeO2 lattice, replacing Ce. Temperature programmed desorption experiments showed that the activation energy of CO2 desorption increased for higher Cu loadings, indicating stronger CO2 adsorption. This phenomenon was attributed to enhanced formation of oxygen vacancies due to Cu doping. X‐ray photoelectron spectroscopy further confirmed the enhanced generation of oxygen vacancies due to Cu incorporation. Catalytic performance evaluation with the H2/CO2 feed in the 300‐600 °C range showed that all catalysts were 100% selective to CO generation, with higher Cu loadings resulting in CO2 conversion close to equilibrium values at 500‐600 °C. The activation energy of the reaction, determined through reaction tests, exhibited a linear relationship with the activation energy of CO2 desorption. The relationship between these two energy barriers is explored, providing valuable insights into the mechanism of RWGS activity enhancement.
通过反向微乳液法合成了铜掺杂铈（CuCeO2）催化剂，Cu/(Cu+Ce) at% 为 0-26.5。对新合成催化剂和废催化剂（反应后）的 X 射线衍射分析表明，氧化铜中没有独立的铜相，这表明 Cu 已融入 CeO2 晶格中，取代了 Ce。温度编程解吸实验表明，铜负载量越高，二氧化碳解吸的活化能越大，这表明二氧化碳的吸附能力越强。这一现象归因于铜掺杂增强了氧空位的形成。X 射线光电子能谱进一步证实了由于掺入了铜，氧空位的生成得到了增强。以 H2/CO2 为原料在 300-600 °C 范围内进行的催化性能评估表明，所有催化剂对 CO 的生成都具有 100% 的选择性，较高的 Cu 负载可使 CO2 转化率接近 500-600 °C 时的平衡值。通过反应测试确定的反应活化能与二氧化碳解吸活化能呈线性关系。对这两种能量障碍之间的关系进行了探讨，为了解 RWGS 活性增强的机理提供了宝贵的见解。
{"title":"Insights into Mechanisms of Reverse Water Gas Shift Activity Enhancement over Reverse Microemulsion‐Synthesized CuCeO2","authors":"Kishore Kandasamy, Yue Yu, Muhammad Waqas Iqbal, Luis Ricardez-Sandoval, Aiping Yu, David Simakov","doi":"10.1002/cnma.202400128","DOIUrl":"https://doi.org/10.1002/cnma.202400128","url":null,"abstract":"Copper‐doped ceria (CuCeO2) catalysts with 0‐26.5 Cu/(Cu+Ce) at% were synthesized via the reverse microemulsion method. X‐ray diffraction analysis of freshly synthesized and spent (post‐reaction) catalysts showed no separate phase of copper of copper oxide, indicating that Cu was incorporated into the CeO2 lattice, replacing Ce. Temperature programmed desorption experiments showed that the activation energy of CO2 desorption increased for higher Cu loadings, indicating stronger CO2 adsorption. This phenomenon was attributed to enhanced formation of oxygen vacancies due to Cu doping. X‐ray photoelectron spectroscopy further confirmed the enhanced generation of oxygen vacancies due to Cu incorporation. Catalytic performance evaluation with the H2/CO2 feed in the 300‐600 °C range showed that all catalysts were 100% selective to CO generation, with higher Cu loadings resulting in CO2 conversion close to equilibrium values at 500‐600 °C. The activation energy of the reaction, determined through reaction tests, exhibited a linear relationship with the activation energy of CO2 desorption. The relationship between these two energy barriers is explored, providing valuable insights into the mechanism of RWGS activity enhancement.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cobalt ferrite (CFO) nanoparticles (NPs) are highly promising for data storage, energy conversion, permanent magnets, and biomedical applications owing to their exceptional magnetic properties. However, the presence of phase impurities (particularly FeO and CoO) can severely degrade their magnetic properties, hindering their practical use. Here, we present a simple post‐synthesis oxidation approach to address this challenge. Our method involves the thermal decomposition of Fe‐Co oleate followed by oxidation using trimethylamine N‐oxide. The results reveal the effective elimination of FeO and CoO impurities and the formation of spinel ferrite crystal structures post‐oxidation with no change in morphology or size. Magnetic measurements demonstrate a significant enhancement in magnetic properties (e.g., magnetic saturation, coercivity, and blocking temperature) in oxidized CFO NPs compared to the non‐oxidized counterparts, indicative of the recovered ferrimagnetic structure upon post‐synthesis oxidation. As expected, the restoration of the ferrimagnetic structure, resulting in improved magnetic anisotropy, led to decreased SAR values as the nanoparticles moved away from the optimal anisotropy range. The study underscores the necessity of post‐synthesis oxidation for ensuring phase purity and enhancing the magnetic properties of CFO NPs, irrespective of the synthesis method. This approach offers a promising route for producing highly functional magnetic nanoparticles for practical applications.
{"title":"Enhancing Crystallinity and Magnetic Properties of Cobalt Ferrite Nanoparticles via Thermal Oxidation","authors":"Kingsley Poon, Gurvinder Singh","doi":"10.1002/cnma.202400168","DOIUrl":"https://doi.org/10.1002/cnma.202400168","url":null,"abstract":"Cobalt ferrite (CFO) nanoparticles (NPs) are highly promising for data storage, energy conversion, permanent magnets, and biomedical applications owing to their exceptional magnetic properties. However, the presence of phase impurities (particularly FeO and CoO) can severely degrade their magnetic properties, hindering their practical use. Here, we present a simple post‐synthesis oxidation approach to address this challenge. Our method involves the thermal decomposition of Fe‐Co oleate followed by oxidation using trimethylamine N‐oxide. The results reveal the effective elimination of FeO and CoO impurities and the formation of spinel ferrite crystal structures post‐oxidation with no change in morphology or size. Magnetic measurements demonstrate a significant enhancement in magnetic properties (e.g., magnetic saturation, coercivity, and blocking temperature) in oxidized CFO NPs compared to the non‐oxidized counterparts, indicative of the recovered ferrimagnetic structure upon post‐synthesis oxidation. As expected, the restoration of the ferrimagnetic structure, resulting in improved magnetic anisotropy, led to decreased SAR values as the nanoparticles moved away from the optimal anisotropy range. The study underscores the necessity of post‐synthesis oxidation for ensuring phase purity and enhancing the magnetic properties of CFO NPs, irrespective of the synthesis method. This approach offers a promising route for producing highly functional magnetic nanoparticles for practical applications.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fan Xu, Yuxin Liu, Jun Zhu, Xin Zhan, Yinmao Dong, Hong Meng, Shujing Li, Yifan He, Ze Zhang
Ceramide3 (Cer3) is one of the important components of stratum corneum (SC) lipids with good moisturizing and repairing properties. However, it suffers from (a) poor solubility, (b) easy crystallization and precipitation, and (c) strong polarity and difficulty in transdermal application. This study aimed to load Cer3 into nanoemulsions (NEs) to overcome these mentioned defects. The optimized NEs formulation was prepared by high pressure homogenization method and characterized by several methods. The optimized ceramide3 nanoemulsions(Cer3‐NEs) exhibited a good physico‐chemical stability over 3 months under different conditions, with droplet size of 103.1 nm, PDI of 0.178, zeta potential of ‐39.09 mV, pH of 6.20 and encapsulation efficiency of 96.39%. Turbiscan results showed that formulations containing Cer3‐NEs have better stability than those containing free Cer3. The dermal delivery ability of Cer3‐NEs was assessed by Franz diffusion and confocal Raman spectroscopy (CRM). In vitro and in vivo penetration studies showed that Cer3‐NEs serum have almost 2‐3 times higher retention in the skin and permeation in the receptor solution compared to serum with free Cer3. The findings show NE is a promising carrier of Cer3 for topical administration in the treatment of dryness and barrier damage due to higher stability and better skin permeability.
{"title":"Optimisation and Characterisation of Improved Nanoemulsion Formulations Containing Ceramide 3","authors":"Fan Xu, Yuxin Liu, Jun Zhu, Xin Zhan, Yinmao Dong, Hong Meng, Shujing Li, Yifan He, Ze Zhang","doi":"10.1002/cnma.202400289","DOIUrl":"https://doi.org/10.1002/cnma.202400289","url":null,"abstract":"Ceramide3 (Cer3) is one of the important components of stratum corneum (SC) lipids with good moisturizing and repairing properties. However, it suffers from (a) poor solubility, (b) easy crystallization and precipitation, and (c) strong polarity and difficulty in transdermal application. This study aimed to load Cer3 into nanoemulsions (NEs) to overcome these mentioned defects. The optimized NEs formulation was prepared by high pressure homogenization method and characterized by several methods. The optimized ceramide3 nanoemulsions(Cer3‐NEs) exhibited a good physico‐chemical stability over 3 months under different conditions, with droplet size of 103.1 nm, PDI of 0.178, zeta potential of ‐39.09 mV, pH of 6.20 and encapsulation efficiency of 96.39%. Turbiscan results showed that formulations containing Cer3‐NEs have better stability than those containing free Cer3. The dermal delivery ability of Cer3‐NEs was assessed by Franz diffusion and confocal Raman spectroscopy (CRM). In vitro and in vivo penetration studies showed that Cer3‐NEs serum have almost 2‐3 times higher retention in the skin and permeation in the receptor solution compared to serum with free Cer3. The findings show NE is a promising carrier of Cer3 for topical administration in the treatment of dryness and barrier damage due to higher stability and better skin permeability.","PeriodicalId":54339,"journal":{"name":"ChemNanoMat","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141867915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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