T. M. Dhanya, M. R. Prathapachandra Kurup, K. J. Rajimon, G. Anjali Krishna, Jibin K. Varughese, K. G. Raghu, Sachin Philip, K. M. Divya, Maria Augustine, P. V. Mohanan
The rise of various diseases demands the development of new agents with antioxidant, antimicrobial, anti-inflammatory, enzyme-inhibiting, and cytotoxic properties. In this study, heterocyclic Schiff base complexes of Cu(II) featuring a benzo[b]thiophene moiety were synthesized and their biological activities evaluated. The complexes were characterized using FT-IR, UV-Vis, and EPR spectroscopy, TG–DTG analysis, magnetic moment measurements, molar conductivity measurements, and elemental analyses. Density functional theory (DFT) calculations were used to optimize the theoretical molecular orbital energies of the copper complexes. The complexes exhibited square pyramidal and square planar geometries. Biological assays demonstrated that these complexes generally outperformed the Schiff base ligands for various activities. The antioxidant capacity, measured via the DPPH assay in methanol, was comparable to those of the BHT and ascorbic acid standards, with 4BNPC showing the lowest IC50 value, which was attributed to the free OH group rather than coordination to the metal center. The anti-bacterial activity was assessed using the agar disc diffusion method against E. coli, P. aeruginosa, B. subtilis, and S. aureus, with BAC showing the largest inhibition zone compared to the others and ciprofloxacin as the reference. The anti-inflammatory activity, evaluated by the HRBC membrane stabilization method, showed that the 4BNPC Cu(II) complex had moderate activity similar to that of diclofenac. Enzyme inhibition studies against α-amylase revealed that the BAC complexes had the highest inhibition values, surpassing those of the Schiff base ligands. Cytotoxicity was assessed using Trypan blue exclusion for DLA and HepG2 cancer cell lines, and the MTT assay for H9c2 human cells. BMPC demonstrated superior cytotoxicity at both high and low concentrations against the normal H9c2 cell line. Among the tested compounds, BNPC showed moderate inhibition against HepG2 cells, while BMPC exhibited the greatest cytotoxicity at higher concentrations, particularly reaching nearly 100% cell death at 200 μg mL−1 in DLA cell lines. This suggests that BMPC is a promising candidate for further pharmacological research, particularly against DLA cells.
{"title":"Unveiling the multifaceted bioactivity of copper(II)–Schiff base complexes: a comprehensive study of antioxidant, anti-bacterial, anti-inflammatory, enzyme inhibition and cytotoxic potentials with DFT insights","authors":"T. M. Dhanya, M. R. Prathapachandra Kurup, K. J. Rajimon, G. Anjali Krishna, Jibin K. Varughese, K. G. Raghu, Sachin Philip, K. M. Divya, Maria Augustine, P. V. Mohanan","doi":"10.1039/d4dt02486a","DOIUrl":"https://doi.org/10.1039/d4dt02486a","url":null,"abstract":"The rise of various diseases demands the development of new agents with antioxidant, antimicrobial, anti-inflammatory, enzyme-inhibiting, and cytotoxic properties. In this study, heterocyclic Schiff base complexes of Cu(<small>II</small>) featuring a benzo[<em>b</em>]thiophene moiety were synthesized and their biological activities evaluated. The complexes were characterized using FT-IR, UV-Vis, and EPR spectroscopy, TG–DTG analysis, magnetic moment measurements, molar conductivity measurements, and elemental analyses. Density functional theory (DFT) calculations were used to optimize the theoretical molecular orbital energies of the copper complexes. The complexes exhibited square pyramidal and square planar geometries. Biological assays demonstrated that these complexes generally outperformed the Schiff base ligands for various activities. The antioxidant capacity, measured <em>via</em> the DPPH assay in methanol, was comparable to those of the BHT and ascorbic acid standards, with 4BNPC showing the lowest IC<small><sub>50</sub></small> value, which was attributed to the free OH group rather than coordination to the metal center. The anti-bacterial activity was assessed using the agar disc diffusion method against <em>E. coli</em>, <em>P. aeruginosa</em>, <em>B. subtilis</em>, and <em>S. aureus</em>, with BAC showing the largest inhibition zone compared to the others and ciprofloxacin as the reference. The anti-inflammatory activity, evaluated by the HRBC membrane stabilization method, showed that the 4BNPC Cu(<small>II</small>) complex had moderate activity similar to that of diclofenac. Enzyme inhibition studies against α-amylase revealed that the BAC complexes had the highest inhibition values, surpassing those of the Schiff base ligands. Cytotoxicity was assessed using Trypan blue exclusion for DLA and HepG2 cancer cell lines, and the MTT assay for H9c2 human cells. BMPC demonstrated superior cytotoxicity at both high and low concentrations against the normal H9c2 cell line. Among the tested compounds, BNPC showed moderate inhibition against HepG2 cells, while BMPC exhibited the greatest cytotoxicity at higher concentrations, particularly reaching nearly 100% cell death at 200 μg mL<small><sup>−1</sup></small> in DLA cell lines. This suggests that BMPC is a promising candidate for further pharmacological research, particularly against DLA cells.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"45 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pawan Kumar, R. K. Chauhan, Bir Sain, Suman L. Jain
Expression of Concern for ‘Photo-induced reduction of CO2 using a magnetically separable Ru-CoPc@TiO2@SiO2@Fe3O4 catalyst under visible light irradiation’ by Pawan Kumar et al., Dalton Trans., 2015, 44, 4546–4553, https://doi.org/10.1039/C4DT02461C.
{"title":"Expression of concern: Photo-induced reduction of CO2 using a magnetically separable Ru-CoPc@TiO2@SiO2@Fe3O4 catalyst under visible light irradiation","authors":"Pawan Kumar, R. K. Chauhan, Bir Sain, Suman L. Jain","doi":"10.1039/d4dt90225d","DOIUrl":"https://doi.org/10.1039/d4dt90225d","url":null,"abstract":"Expression of Concern for ‘Photo-induced reduction of CO<small><sub>2</sub></small> using a magnetically separable Ru-CoPc@TiO<small><sub>2</sub></small>@SiO<small><sub>2</sub></small>@Fe<small><sub>3</sub></small>O<small><sub>4</sub></small> catalyst under visible light irradiation’ by Pawan Kumar <em>et al.</em>, <em>Dalton Trans</em>., 2015, <strong>44</strong>, 4546–4553, https://doi.org/10.1039/C4DT02461C.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"42 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oviya Sekar, F. Irine Maria Bincy, Raju Suresh Kumar, Kannappan Perumal, Ikhyun Kim, S. A. Martin Britto Dhas
In this study, Zinc Telluride (ZnTe) was subjected to acoustic shock waves with a Mach number of 1.5, transient pressure of 0.59 MPa, and a temperature of 520 K to analyze its stability against shock wave impact. ZnTe was exposed to different shock pulses, such as 100, 200, 300, and 400. The stability was assessed through multiple characterization techniques such as Powder X-ray diffraction (PXRD), Raman spectroscopy, Ultraviolet diffuse reflectance spectroscopy (UV-DRS) analysis, Photoluminescence (PL) spectroscopy, and Scanning Electron Microscopy (SEM). The X-ray diffraction pattern revealed a phase transition at 300 shock pulses from cubic (F3m) to cubic (Fmm). Interestingly, at 400 shock pulses, the original cubic (F3m) phase was restored. The Raman spectrum showed the disappearance, intensity variation, and shift of Raman peaks, particularly at 300 shock pulses, which reverted to the original state at 400 pulses, indicating a reversible phase transition. The absorption spectrum exhibited a lower angle shift and a change in band gap from 2.85 eV to 2.63 eV at 300 shock pulses. However, the band gap was reduced to 2.8 eV at 400 shock pulses. The photoluminescence spectrum showed high intensity specifically at 300 shock-loaded conditions. Morphological analysis revealed a change from irregular shapes to plate-like structures at 300 shock pulses. The results confirm that shock waves significantly impact ZnTe, inducing a reversible phase transition.
{"title":"Reversible phase transition and tunable band gap in zinc telluride induced by acoustic shock exposure","authors":"Oviya Sekar, F. Irine Maria Bincy, Raju Suresh Kumar, Kannappan Perumal, Ikhyun Kim, S. A. Martin Britto Dhas","doi":"10.1039/d4dt03393k","DOIUrl":"https://doi.org/10.1039/d4dt03393k","url":null,"abstract":"In this study, Zinc Telluride (ZnTe) was subjected to acoustic shock waves with a Mach number of 1.5, transient pressure of 0.59 MPa, and a temperature of 520 K to analyze its stability against shock wave impact. ZnTe was exposed to different shock pulses, such as 100, 200, 300, and 400. The stability was assessed through multiple characterization techniques such as Powder X-ray diffraction (PXRD), Raman spectroscopy, Ultraviolet diffuse reflectance spectroscopy (UV-DRS) analysis, Photoluminescence (PL) spectroscopy, and Scanning Electron Microscopy (SEM). The X-ray diffraction pattern revealed a phase transition at 300 shock pulses from cubic (<em>F</em><img alt=\"[4 with combining macron]\" border=\"0\" src=\"https://www.rsc.org/images/entities/char_0034_0304.gif\"/>3<em>m</em>) to cubic (<em>Fm</em><img alt=\"[3 with combining macron]\" border=\"0\" src=\"https://www.rsc.org/images/entities/char_0033_0304.gif\"/><em>m</em>). Interestingly, at 400 shock pulses, the original cubic (<em>F</em><img alt=\"[4 with combining macron]\" border=\"0\" src=\"https://www.rsc.org/images/entities/char_0034_0304.gif\"/>3<em>m</em>) phase was restored. The Raman spectrum showed the disappearance, intensity variation, and shift of Raman peaks, particularly at 300 shock pulses, which reverted to the original state at 400 pulses, indicating a reversible phase transition. The absorption spectrum exhibited a lower angle shift and a change in band gap from 2.85 eV to 2.63 eV at 300 shock pulses. However, the band gap was reduced to 2.8 eV at 400 shock pulses. The photoluminescence spectrum showed high intensity specifically at 300 shock-loaded conditions. Morphological analysis revealed a change from irregular shapes to plate-like structures at 300 shock pulses. The results confirm that shock waves significantly impact ZnTe, inducing a reversible phase transition.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"33 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Subodh Kumar, Nikita Singhal, Raj K. Singh, Piyush Gupta, Raghuvir Singh, Suman L. Jain
Retraction of ‘Dual catalysis with magnetic chitosan: direct synthesis of cyclic carbonates from olefins with carbon dioxide using isobutyraldehyde as the sacrificial reductant’ by Subodh Kumar et al., Dalton Trans., 2015, 44, 11860–11866, https://doi.org/10.1039/C5DT01012H.
{"title":"Retraction: Dual catalysis with magnetic chitosan: direct synthesis of cyclic carbonates from olefins with carbon dioxide using isobutyraldehyde as the sacrificial reductant","authors":"Subodh Kumar, Nikita Singhal, Raj K. Singh, Piyush Gupta, Raghuvir Singh, Suman L. Jain","doi":"10.1039/d4dt90226b","DOIUrl":"https://doi.org/10.1039/d4dt90226b","url":null,"abstract":"Retraction of ‘Dual catalysis with magnetic chitosan: direct synthesis of cyclic carbonates from olefins with carbon dioxide using isobutyraldehyde as the sacrificial reductant’ by Subodh Kumar <em>et al.</em>, <em>Dalton Trans.</em>, 2015, <strong>44</strong>, 11860–11866, https://doi.org/10.1039/C5DT01012H.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"83 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lusheng Xiao, Danqi Jia, Chen Chen, Tingting Liu, Xiaofeng Zhang, Qiufeng Huang, Mohd Ubaidullah, Yuzhi Sun, Shengyun Huang, Zonghua Pu
The development of Pd-based materials with high activity and long-term stability are crucial for their practical applications as an anode catalyst in direct formic acid fuel cells. Herein, we reveal that the catalytic activity of Pd towards formic acid oxidation can be enhanced by incorporation a series of rare-earth oxide, including Sc2O3, CeO2, La2O3, and Pr2O3, etc. As an example, the Pd nanoparticles incorporated with Sc2O3 supported on nitrogen doped reduced graphene oxide (Pd-Sc2O3/N-rGO-x, x = 1/3, 1/2, 2/3, 1, 3/2; "x" denotes the molar ratio of Pd: Sc) can be obtained using sodium borohydride reduction method. When directly used Pd-Sc2O3/N-rGO-2/3 as an electrocatalyst towards formic acid oxidation (FAO). The Pd-Sc2O3/N-rGO-2/3 shows the highest mass current density of 972.9 mA mg-1Pd, surpassing that of the reference catalysts Pd/C (262.6 mA mg-1Pd) and Pd/N-rGO (304.9 mA mg-1Pd). More importantly, the Pd-Sc2O3/N-rGO-2/3 catalyst also shows high CO tolerance and long-term stability in FAO reaction. The improved electrooxidation activity and stability could be attributed to the synergistic effect between Sc2O3 and Pd nanoparticles. Therefore, this study presents a crucial contribution to the advancement of various rare-earth oxides for enhancing Pd activity towards FAO and beyond.
{"title":"Rare-earth oxides promoted Pd electrocatalyst for formic acid oxidation","authors":"Lusheng Xiao, Danqi Jia, Chen Chen, Tingting Liu, Xiaofeng Zhang, Qiufeng Huang, Mohd Ubaidullah, Yuzhi Sun, Shengyun Huang, Zonghua Pu","doi":"10.1039/d4dt03296a","DOIUrl":"https://doi.org/10.1039/d4dt03296a","url":null,"abstract":"The development of Pd-based materials with high activity and long-term stability are crucial for their practical applications as an anode catalyst in direct formic acid fuel cells. Herein, we reveal that the catalytic activity of Pd towards formic acid oxidation can be enhanced by incorporation a series of rare-earth oxide, including Sc2O3, CeO2, La2O3, and Pr2O3, etc. As an example, the Pd nanoparticles incorporated with Sc2O3 supported on nitrogen doped reduced graphene oxide (Pd-Sc2O3/N-rGO-x, x = 1/3, 1/2, 2/3, 1, 3/2; \"x\" denotes the molar ratio of Pd: Sc) can be obtained using sodium borohydride reduction method. When directly used Pd-Sc2O3/N-rGO-2/3 as an electrocatalyst towards formic acid oxidation (FAO). The Pd-Sc2O3/N-rGO-2/3 shows the highest mass current density of 972.9 mA mg-1Pd, surpassing that of the reference catalysts Pd/C (262.6 mA mg-1Pd) and Pd/N-rGO (304.9 mA mg-1Pd). More importantly, the Pd-Sc2O3/N-rGO-2/3 catalyst also shows high CO tolerance and long-term stability in FAO reaction. The improved electrooxidation activity and stability could be attributed to the synergistic effect between Sc2O3 and Pd nanoparticles. Therefore, this study presents a crucial contribution to the advancement of various rare-earth oxides for enhancing Pd activity towards FAO and beyond.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"96 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kimberly Weston, Richard A. Taylor, Kim Kisslinger, Shobha Mantripragada
Facile phase selective synthesis of copper antimony sulphide (CAS) nanostructures is important because of their tunable photoconductive and electrochemical properties. In this study, off-stoichiometric famatinite phase CAS (fCAS) quasi-spherical and quasi-hexagonal colloidal nanostructures (including nanosheets) of sizes, 2.4–18.0 nm were grown under variable conditions of temperature (60–200 °C), time and oleylamine capping ligand concentration using copper(II) acetylacetonate and antimony(III) diethyldithiocarbamate precursors. Data from powder X-ray diffraction, Raman spectroscopy and high-resolution scanning/transmission electron microscopy confirm the tetragonal structure of the famatinite phase. X-ray photoelectron spectroscopy, transmission electron microscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy data suggest a correlation of particle size, morphology and composition of the off-stoichiometric fCAS nanostructures with growth temperature and time, and oleylamine concentration. The off-stoichiometric Cu3−aSb1+bS4±c (a, b, c – mole fractions) nanostructures being severely copper-deficient and antimony-rich, exhibit shallow-lying acceptor copper vacancy states, deep-lying donor states of antimony interstitials, sulphur vacancies and antimony-copper antisites and shallow-lying acceptor surface trapping states. These electronic states are likely implicated in tunable UV-visible absorption and bandgaps between 2.3 and 2.8 eV, and broad visible-NIR photoluminescence with fast recombination of radiative lifetimes between 0.2 and 6.2 ns, confirmed from absorption, steady-state and time-resolved photoluminescence spectroscopies. Additionally, cyclic voltammetry and electrochemical impedance spectroscopy confirm that electrodes of the fCAS nanostructures display slightly variable pseudocapacitance of charge-storage primarily via possible sodium ion intercalation with a high specific capacitance of ∼84 F g−1 obtained at a scan rate of 5 mV s−1. Overall, these results show the influence of composition, in particular point defects, phase quality and morphology on the optical and pseudocapacitance properties of fCAS nanostructures, suitable as solar absorbers or electrodes for energy storage devices.
{"title":"Effect of growth dynamics on the structural, photophysical and pseudocapacitance properties of famatinite copper antimony sulphide colloidal nanostructures (including nanosheets)","authors":"Kimberly Weston, Richard A. Taylor, Kim Kisslinger, Shobha Mantripragada","doi":"10.1039/d4dt02826k","DOIUrl":"https://doi.org/10.1039/d4dt02826k","url":null,"abstract":"Facile phase selective synthesis of copper antimony sulphide (CAS) nanostructures is important because of their tunable photoconductive and electrochemical properties. In this study, off-stoichiometric famatinite phase CAS (<em>f</em>CAS) quasi-spherical and quasi-hexagonal colloidal nanostructures (including nanosheets) of sizes, 2.4–18.0 nm were grown under variable conditions of temperature (60–200 °C), time and oleylamine capping ligand concentration using copper(<small>II</small>) acetylacetonate and antimony(<small>III</small>) diethyldithiocarbamate precursors. Data from powder X-ray diffraction, Raman spectroscopy and high-resolution scanning/transmission electron microscopy confirm the tetragonal structure of the famatinite phase. X-ray photoelectron spectroscopy, transmission electron microscopy and scanning electron microscopy-energy dispersive X-ray spectroscopy data suggest a correlation of particle size, morphology and composition of the off-stoichiometric <em>f</em>CAS nanostructures with growth temperature and time, and oleylamine concentration. The off-stoichiometric Cu<small><sub>3−<em>a</em></sub></small>Sb<small><sub>1+<em>b</em></sub></small>S<small><sub>4<em>±c</em></sub></small> (<em>a</em>, <em>b</em>, <em>c</em> – mole fractions) nanostructures being severely copper-deficient and antimony-rich, exhibit shallow-lying acceptor copper vacancy states, deep-lying donor states of antimony interstitials, sulphur vacancies and antimony-copper antisites and shallow-lying acceptor surface trapping states. These electronic states are likely implicated in tunable UV-visible absorption and bandgaps between 2.3 and 2.8 eV, and broad visible-NIR photoluminescence with fast recombination of radiative lifetimes between 0.2 and 6.2 ns, confirmed from absorption, steady-state and time-resolved photoluminescence spectroscopies. Additionally, cyclic voltammetry and electrochemical impedance spectroscopy confirm that electrodes of the <em>f</em>CAS nanostructures display slightly variable pseudocapacitance of charge-storage primarily <em>via</em> possible sodium ion intercalation with a high specific capacitance of ∼84 F g<small><sup>−1</sup></small> obtained at a scan rate of 5 mV s<small><sup>−1</sup></small>. Overall, these results show the influence of composition, in particular point defects, phase quality and morphology on the optical and pseudocapacitance properties of <em>f</em>CAS nanostructures, suitable as solar absorbers or electrodes for energy storage devices.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"55 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jarrod R. Thomas, Marcus J. Giansiracusa, Jonathan T. Mifsud, Richard A. Mole, Scott A. Sulway
The synthesis and structural characterisation of [Ln(Tp2-Fu)2]I (1-Ln; Ln = La, Ce, Pr, Nd) (Tp2-Fu = hydrotris(3-(2′-furyl)-pyrazol-1-yl)borate) have been reported as an isomorphous series adopting pseudo-icosahedral ligand field geometries. Continuous shape measurement (CShM) analyses on the crystal field environments of 1-Ln show the smallest values yet reported for complexes employing two hexadentate ligands (e.g. bis-scorpionate environments), with the smallest belonging to 1-La. Single-ion magnetism for 1-Ce, 1-Pr and 1-Nd was probed with ac magnetic susceptibility studies revealing slow magnetic relaxation for 1-Nd in applied magnetic fields and in zero-applied field for 1-Ce, which is a rare observation for Ce(III)-based single-ion magnets. The energy barrier to magnetic relaxation for 1-Ce was experimentally determined to be Ueff = 30(5) cm−1, which is comparable to that of other cerium-based single-molecule magnets in the literature, where these systems stablise the mJ = ±5/2 state and possess large energy gaps between the ground and first excited state that do not agree with the experimentally determined barrier.
{"title":"A rare case of a zero-field single-ion magnet in a cerium(III) pseudo-icosahedral complex","authors":"Jarrod R. Thomas, Marcus J. Giansiracusa, Jonathan T. Mifsud, Richard A. Mole, Scott A. Sulway","doi":"10.1039/d4dt03231d","DOIUrl":"https://doi.org/10.1039/d4dt03231d","url":null,"abstract":"The synthesis and structural characterisation of [Ln(Tp<small><sup>2-Fu</sup></small>)<small><sub>2</sub></small>]I (<strong>1-Ln</strong>; Ln = La, Ce, Pr, Nd) (Tp<small><sup>2-Fu</sup></small> = hydrotris(3-(2′-furyl)-pyrazol-1-yl)borate) have been reported as an isomorphous series adopting pseudo-icosahedral ligand field geometries. Continuous shape measurement (CShM) analyses on the crystal field environments of <strong>1-Ln</strong> show the smallest values yet reported for complexes employing two hexadentate ligands (<em>e.g. bis</em>-scorpionate environments), with the smallest belonging to <strong>1-La</strong>. Single-ion magnetism for <strong>1-Ce</strong>, <strong>1-Pr</strong> and <strong>1-Nd</strong> was probed with ac magnetic susceptibility studies revealing slow magnetic relaxation for <strong>1-Nd</strong> in applied magnetic fields and in zero-applied field for <strong>1-Ce</strong>, which is a rare observation for Ce(<small>III</small>)-based single-ion magnets. The energy barrier to magnetic relaxation for <strong>1-Ce</strong> was experimentally determined to be <em>U</em><small><sub>eff</sub></small> = 30(5) cm<small><sup>−1</sup></small>, which is comparable to that of other cerium-based single-molecule magnets in the literature, where these systems stablise the <em>m</em><small><sub><em>J</em></sub></small> = ±5/2 state and possess large energy gaps between the ground and first excited state that do not agree with the experimentally determined barrier.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"16 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuan Liu, Xingyuan Zhou, Yupei Wu, Hongwei Zhang, Kun Cao
Formamidine lead triiodide (FAPbI3) has received significant attention in the field of perovskite solar cells (PSCs) owing to its excellent optoelectronic properties and high thermal stability. However, the photoactive α-FAPbI3 perovskites are highly susceptible to degradation into non-perovskite δ-FAPbI3 phases especially under humid conditions, which severely diminishes the device performance of FAPbI3 PSCs. Here, we propose an interfacial seeding strategy for regulating crystallization and stabilizing α-FAPbI3 perovskites in humid air. By post-treating the antisolvent-free, air-processed perovskite wet film with inorganic cesium lead triiodide (CsPbI3) nanocrystals, a functional seed layer is formed that effectively mitigates the erosion by humid air while facilitating the conversion of intermediates to the α-FAPbI3 phase. The interfacial seed-modified FAPbI3 perovskite films exhibit improved crystal quality and denser morphology. As a result, the efficiency of all-air-processed carbon-based PSCs is improved from 15.90% for the control to 18.04%. In addition, the unencapsulated PSCs based on interfacial seed-modified FAPbI3 films show improved environmental stability compared to the control counterparts, maintaining 80% of its initial efficiency after 60 days.
{"title":"Interfacial seed-assisted FAPbI3 crystallization and phase stabilization enhances the performance of all-air-processed perovskite solar cells","authors":"Yuan Liu, Xingyuan Zhou, Yupei Wu, Hongwei Zhang, Kun Cao","doi":"10.1039/d4dt03120b","DOIUrl":"https://doi.org/10.1039/d4dt03120b","url":null,"abstract":"Formamidine lead triiodide (FAPbI3) has received significant attention in the field of perovskite solar cells (PSCs) owing to its excellent optoelectronic properties and high thermal stability. However, the photoactive α-FAPbI3 perovskites are highly susceptible to degradation into non-perovskite δ-FAPbI3 phases especially under humid conditions, which severely diminishes the device performance of FAPbI3 PSCs. Here, we propose an interfacial seeding strategy for regulating crystallization and stabilizing α-FAPbI3 perovskites in humid air. By post-treating the antisolvent-free, air-processed perovskite wet film with inorganic cesium lead triiodide (CsPbI3) nanocrystals, a functional seed layer is formed that effectively mitigates the erosion by humid air while facilitating the conversion of intermediates to the α-FAPbI3 phase. The interfacial seed-modified FAPbI3 perovskite films exhibit improved crystal quality and denser morphology. As a result, the efficiency of all-air-processed carbon-based PSCs is improved from 15.90% for the control to 18.04%. In addition, the unencapsulated PSCs based on interfacial seed-modified FAPbI3 films show improved environmental stability compared to the control counterparts, maintaining 80% of its initial efficiency after 60 days.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"55 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Di Chen, Zhaobin Ye, Jie Xu, Shasha Ma, Jianyong Zhang
Electrochemical nitrate reduction reaction (NO3RR) is considered as a promising strategy for environment pollution governing and sustainable energy development. In this study, prism-like CuO loaded on copper foam (CuO/CF) was synthesized in simple solvothermal reaction and in-situ electrochemical reconstruction process. The electrochemical reconstruction process facilitates the formation of CuO lattice structure on copper foam derived from FU-CF generated by the reaction of copper foam and fumaric acid (H2FU) in DMF. The prism-like CuO on the surface of copper foam served as a remarkable electrocatalyst for electrochemical nitrate reduction reaction, regulating the rate of electron transport and maintaining an ordered structure. The prism-like CuO lattice structure demonstrated a Faradaic efficiency of 95.66%, ammonia yield of 0.741 mmol h-1 cm-2 and NH3 selectivity of 96.38%. This work provides a feasible strategy for fabricating Cu-based electrocatalysts in green energy and environment field.
{"title":"In-situ reconstructed prism-like CuO on copper foam assisted by fumaric acid for enhanced electrochemical nitrate reduction reaction","authors":"Di Chen, Zhaobin Ye, Jie Xu, Shasha Ma, Jianyong Zhang","doi":"10.1039/d4dt03404j","DOIUrl":"https://doi.org/10.1039/d4dt03404j","url":null,"abstract":"Electrochemical nitrate reduction reaction (NO3RR) is considered as a promising strategy for environment pollution governing and sustainable energy development. In this study, prism-like CuO loaded on copper foam (CuO/CF) was synthesized in simple solvothermal reaction and in-situ electrochemical reconstruction process. The electrochemical reconstruction process facilitates the formation of CuO lattice structure on copper foam derived from FU-CF generated by the reaction of copper foam and fumaric acid (H2FU) in DMF. The prism-like CuO on the surface of copper foam served as a remarkable electrocatalyst for electrochemical nitrate reduction reaction, regulating the rate of electron transport and maintaining an ordered structure. The prism-like CuO lattice structure demonstrated a Faradaic efficiency of 95.66%, ammonia yield of 0.741 mmol h-1 cm-2 and NH3 selectivity of 96.38%. This work provides a feasible strategy for fabricating Cu-based electrocatalysts in green energy and environment field.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"27 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fe–N–C catalysts are considered promising substitutes for Pt-based catalysts at the cathode in direct methanol fuel cells (DMFCs) owing to their great methanol tolerance. However, Fe–N–C-based DMFCs commonly suffer from a decreased performance under extremely high methanol concentrations and exhibit poor stability, while the underlying mechanism remains controversial. In this study, a self-degradation phenomenon in a passive Fe–N–C-based DMFC was investigated in detail. The DMFC with an optimized ionomer content and catalyst loading delivered an extremely high peak power density of 28.85 mW cm−2 when fed with 3 M methanol solution, while the peak power density of the cell rapidly declined to 16.61 mW cm−2 after standing for 10 days without any discharging operation. Several electrochemical measurements were designed and conducted to explore the mechanism for this phenomenon. The results of these measurements revealed that methanol molecules are chemically adsorbed on the surface of the Fe–N–C catalyst, and the bonding cannot be reversed using simple physical methods, leading to the isolation of active sites from oxygen. Herein, we provide a new perspective on passive Fe–N–C-based DMFCs that would be significant for the technological development of portable power devices.
{"title":"Study of the self-degradation performance of a passive direct methanol fuel cell with an Fe–N–C catalyst","authors":"Chenjun Hou, Weijian Yuan, Shilong Gao, Yujun Zhang, Yufeng Zhang, Xuelin Zhang","doi":"10.1039/d4dt03024a","DOIUrl":"https://doi.org/10.1039/d4dt03024a","url":null,"abstract":"Fe–N–C catalysts are considered promising substitutes for Pt-based catalysts at the cathode in direct methanol fuel cells (DMFCs) owing to their great methanol tolerance. However, Fe–N–C-based DMFCs commonly suffer from a decreased performance under extremely high methanol concentrations and exhibit poor stability, while the underlying mechanism remains controversial. In this study, a self-degradation phenomenon in a passive Fe–N–C-based DMFC was investigated in detail. The DMFC with an optimized ionomer content and catalyst loading delivered an extremely high peak power density of 28.85 mW cm<small><sup>−2</sup></small> when fed with 3 M methanol solution, while the peak power density of the cell rapidly declined to 16.61 mW cm<small><sup>−2</sup></small> after standing for 10 days without any discharging operation. Several electrochemical measurements were designed and conducted to explore the mechanism for this phenomenon. The results of these measurements revealed that methanol molecules are chemically adsorbed on the surface of the Fe–N–C catalyst, and the bonding cannot be reversed using simple physical methods, leading to the isolation of active sites from oxygen. Herein, we provide a new perspective on passive Fe–N–C-based DMFCs that would be significant for the technological development of portable power devices.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"30 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142988091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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3m) to cubic (Fm![[3 with combining macron]](https://www.rsc.org/images/entities/char_0033_0304.gif)
m). Interestingly, at 400 shock pulses, the original cubic (F
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