María Puerto-Jiménez, Enqi Bu, Daniel Goma Jiménez, Almudena Aguinaco, Juan J Delgado, Jose Pintado, Ginesa Blanco, Adrián Bogeat-Barroso
The development of efficient visible light photocatalysts based on ceria (CeO2) requires precise control over both morphology and electronic band structure. Herein, a facile one-pot hydrothermal method is reported for the preparation of crystallographically well-defined ceria nanocubes featuring enhanced photocatalytic response under visible light irradiation. The proposed approach relies on the in situ structural incorporation of 1,10-phenanthroline during crystal growth. Unlike conventional doping or surface functionalisation strategies, this method yields organic–inorganic nanostructured hybrid materials where the organic moiety is effectively incorporated into the fluorite-type ceria lattice through the formation of Ce-N coordination bonds, while preserving the cubic morphology enclosed by reactive {100} facets and simultaneously increasing specific surface area. Diffuse reflectance UV–Vis spectroscopy and valence band XPS analyses reveal that this integration induces the appearance of N 2p intraband gap states associated with the Ce-N bonds, resulting in a significant narrowing of the optical band gap and extending the light absorption edge into the visible region. Consequently, these organoceria hybrids exhibit a remarkable synergistic enhancement in photocatalytic hydrogen production via ethanol photoreforming under simulated solar irradiation, with hydrogen evolution rates 7.5 times higher than those of pristine ceria nanocubes. This work demonstrates the potential of organic ligand-assisted lattice engineering as a versatile approach to tailor the optoelectronic properties of ceria, thus opening new avenues for sustainable solar-to-chemical energy conversion.
{"title":"Organoceria nanostructured hybrid materials: a novel approach for band gap modulation in ceria","authors":"María Puerto-Jiménez, Enqi Bu, Daniel Goma Jiménez, Almudena Aguinaco, Juan J Delgado, Jose Pintado, Ginesa Blanco, Adrián Bogeat-Barroso","doi":"10.1039/d6dt00140h","DOIUrl":"https://doi.org/10.1039/d6dt00140h","url":null,"abstract":"The development of efficient visible light photocatalysts based on ceria (CeO<small><sub>2</sub></small>) requires precise control over both morphology and electronic band structure. Herein, a facile one-pot hydrothermal method is reported for the preparation of crystallographically well-defined ceria nanocubes featuring enhanced photocatalytic response under visible light irradiation. The proposed approach relies on the <em>in situ</em> structural incorporation of 1,10-phenanthroline during crystal growth. Unlike conventional doping or surface functionalisation strategies, this method yields organic–inorganic nanostructured hybrid materials where the organic moiety is effectively incorporated into the fluorite-type ceria lattice through the formation of Ce-N coordination bonds, while preserving the cubic morphology enclosed by reactive {100} facets and simultaneously increasing specific surface area. Diffuse reflectance UV–Vis spectroscopy and valence band XPS analyses reveal that this integration induces the appearance of N 2<em>p</em> intraband gap states associated with the Ce-N bonds, resulting in a significant narrowing of the optical band gap and extending the light absorption edge into the visible region. Consequently, these organoceria hybrids exhibit a remarkable synergistic enhancement in photocatalytic hydrogen production via ethanol photoreforming under simulated solar irradiation, with hydrogen evolution rates 7.5 times higher than those of pristine ceria nanocubes. This work demonstrates the potential of organic ligand-assisted lattice engineering as a versatile approach to tailor the optoelectronic properties of ceria, thus opening new avenues for sustainable solar-to-chemical energy conversion.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"79 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384164","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}
Carlos J Carrasco,Regla Ayala,Sara Garrido,Francisco Montilla,Agustín Galindo
Silver nanoparticles stabilized by amino acid-derived N-heterocyclic carbenes, denoted as Ag(NHCR)-NPs (R = H, 3a; Me, 3b; iPr, 3c; and iBu, 3d), were synthesized by reducing the parent complexes Na3[Ag(NHCR)2] (2a-d) with NaBH4 under appropriate reaction conditions. The stability of the aqueous AgNP solutions was found to depend strongly on the presence of the NHC ligand, the solution concentration, and the nature of the R substituent. In particular, the stability of the nanoparticles decreases as the steric bulk of R increases. Among the series, 3a (R = H) exhibits remarkable stability in water and can be isolated by ultracentrifugation and lyophilization. Notably, solid Ag(NHCH)-NPs (3a) can be redissolved in water to regenerate a stable AgNP solution. The Ag(NHCR)-NPs were characterized by infrared (IR) and ultraviolet-visible (UV-Vis) spectroscopies, polarimetry, dynamic light scattering (DLS), and transmission electron microscopy (TEM). 3a behaves as an active and versatile nanocatalyst in water, efficiently promoting both the model reduction of 4-nitrophenol to 4-aminophenol and the catalytic hydrolysis of NaBH4 to generate H2 under basic conditions. From a theoretical perspective, the nucleation and growth of the Ag(NHCR)-NPs were modelled using density functional theory (DFT) at the PBE-D3/def2-TZVP level, considering systems of the type [Agn(NHCR)]2- (with R = H, Me and iPr and n = 2, 3, 4, 20, 30). The Quantum Theory of Atoms in Molecules (QTAIM) was employed to analyze the bonding characteristics within the nanoparticles, with particular attention to the Ag-Ag and Ag-C(carbene) interactions. It is noteworthy that the bond dissociation energy (BDE) of the Ag-C(carbene) bond decreases with increasing steric bulk of R, consistent with the experimental observations. Based on experimental data, the Ag : NHC ratio is approximately 30 : 1 and the calculated IR spectrum of [Ag30(NHCH)]2- model (corresponding to 3a) provides a satisfactory match with the experimental spectrum.
{"title":"Water-soluble silver nanoparticles stabilized by amino acid-derived N-heterocyclic carbenes: synthesis, properties and theoretical study of the nucleation process.","authors":"Carlos J Carrasco,Regla Ayala,Sara Garrido,Francisco Montilla,Agustín Galindo","doi":"10.1039/d6dt00206d","DOIUrl":"https://doi.org/10.1039/d6dt00206d","url":null,"abstract":"Silver nanoparticles stabilized by amino acid-derived N-heterocyclic carbenes, denoted as Ag(NHCR)-NPs (R = H, 3a; Me, 3b; iPr, 3c; and iBu, 3d), were synthesized by reducing the parent complexes Na3[Ag(NHCR)2] (2a-d) with NaBH4 under appropriate reaction conditions. The stability of the aqueous AgNP solutions was found to depend strongly on the presence of the NHC ligand, the solution concentration, and the nature of the R substituent. In particular, the stability of the nanoparticles decreases as the steric bulk of R increases. Among the series, 3a (R = H) exhibits remarkable stability in water and can be isolated by ultracentrifugation and lyophilization. Notably, solid Ag(NHCH)-NPs (3a) can be redissolved in water to regenerate a stable AgNP solution. The Ag(NHCR)-NPs were characterized by infrared (IR) and ultraviolet-visible (UV-Vis) spectroscopies, polarimetry, dynamic light scattering (DLS), and transmission electron microscopy (TEM). 3a behaves as an active and versatile nanocatalyst in water, efficiently promoting both the model reduction of 4-nitrophenol to 4-aminophenol and the catalytic hydrolysis of NaBH4 to generate H2 under basic conditions. From a theoretical perspective, the nucleation and growth of the Ag(NHCR)-NPs were modelled using density functional theory (DFT) at the PBE-D3/def2-TZVP level, considering systems of the type [Agn(NHCR)]2- (with R = H, Me and iPr and n = 2, 3, 4, 20, 30). The Quantum Theory of Atoms in Molecules (QTAIM) was employed to analyze the bonding characteristics within the nanoparticles, with particular attention to the Ag-Ag and Ag-C(carbene) interactions. It is noteworthy that the bond dissociation energy (BDE) of the Ag-C(carbene) bond decreases with increasing steric bulk of R, consistent with the experimental observations. Based on experimental data, the Ag : NHC ratio is approximately 30 : 1 and the calculated IR spectrum of [Ag30(NHCH)]2- model (corresponding to 3a) provides a satisfactory match with the experimental spectrum.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"231 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147383363","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}
Gigantic polyoxomolybdates, dominated by the Molybdenum Blue (MB) family, constitute a key subclass of polyoxometalates (POMs) and play a fundamental role in elucidating structural construction principles and showcasing the diversity of POM architectures. Since the first structural determination of the iconic {Mo154} big wheel cluster, these giant polyoxomolybdates have been developed rapidly over the past three decades, emerging as one of the most versatile classes of POM clusters. Potential applications span materials science, catalysis, nanotechnology, and biomedicine. This tutorial review summarises the fundamentals of MBs and their close relatives including the highly reduced Mo browns and Mo reds, their molecular and electronic structures, physical properties, and synthetic methods for production. Drawing on approximately 70 references from pivotal studies over the last thirty years, this review serves as both an authoritative reference for early-career researchers and an accessible introduction for non-professionals interested in this dynamic field.
{"title":"Spontaneous assemblies of gigantic poly-oxomolybdates; from structure and properties to synthetic methods","authors":"Vishal Lakhanpal, Deliang Long, Lee Cronin","doi":"10.1039/d5dt03084f","DOIUrl":"https://doi.org/10.1039/d5dt03084f","url":null,"abstract":"Gigantic polyoxomolybdates, dominated by the Molybdenum Blue (MB) family, constitute a key subclass of polyoxometalates (POMs) and play a fundamental role in elucidating structural construction principles and showcasing the diversity of POM architectures. Since the first structural determination of the iconic {Mo154} big wheel cluster, these giant polyoxomolybdates have been developed rapidly over the past three decades, emerging as one of the most versatile classes of POM clusters. Potential applications span materials science, catalysis, nanotechnology, and biomedicine. This tutorial review summarises the fundamentals of MBs and their close relatives including the highly reduced Mo browns and Mo reds, their molecular and electronic structures, physical properties, and synthetic methods for production. Drawing on approximately 70 references from pivotal studies over the last thirty years, this review serves as both an authoritative reference for early-career researchers and an accessible introduction for non-professionals interested in this dynamic field.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"1 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147454533","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}
Oluseun Akintola, Sudhir Lima, Michael Seifert, Benjamin Kintzel, Helmar Görls, Rupam Dinda, Winfried Plass
We report two chemically very similar non-oxido V(IV) complexes that feature distorted octahedral and distorted trigonal prismatic coordination geometries, as elucidated by single-crystal X-ray diffraction. Both compounds are thermally stable and show no degradation in the presence of air or water. An in-depth echo-detected field-sweep (EDFS) ESR spectroscopic study in frozen solution at temperatures below 10 K revealed resolved hyperfine interactions with the spin-bearing 51V nucleus, along with additional couplings to neighboring 14N and 1H nuclei detected in ESEEM experiments. Investigation of the spin dynamics, and of the potential influence of the distinct coordination geometries, yielded long spin-lattice relaxation times (T1) exceeding 100 ms at 5 K, which decreased to about 40 µs at 50 K. These long T1 times therefore do not limit the spin coherence, and consequently the phase-memory times (Tm), at very low temperatures. The latter ranged from 5 to 8 µs and exhibited negligible temperature dependence within the investigated range. However, the use of a deuterated solvent increased Tm by approximately one order of magnitude to 52 µs at 5 K, though it also resulted in a more pronounced temperature dependence. Coherent spin manipulation was demonstrated by echo-detected transient nutation experiments, revealing well-defined Rabi oscillations with frequencies in the range of 13 MHz at an attenuation level of 9 dB and figures of merit exceeding 103 in deuterated solvent. Cluster correlation expansion (CCE) simulations reproduce the experimentally observed trends and identify the surrounding nuclear spin bath as the dominant decoherence source under dilution-limit conditions. No significant differences attributable to the distinct coordination geometries or structural variations in the ligand backbone were observed. These findings establish the present vanadium(IV) complexes as competitive candidates for molecular spin qubits and promising targets for future surface-deposition studies
{"title":"Spin dynamics and long phase-memory times in structurally distinct non-oxido vanadium(IV) complexes with rigid ligand frameworks relevant to molecular qubits","authors":"Oluseun Akintola, Sudhir Lima, Michael Seifert, Benjamin Kintzel, Helmar Görls, Rupam Dinda, Winfried Plass","doi":"10.1039/d5dt02909k","DOIUrl":"https://doi.org/10.1039/d5dt02909k","url":null,"abstract":"We report two chemically very similar non-oxido V(IV) complexes that feature distorted octahedral and distorted trigonal prismatic coordination geometries, as elucidated by single-crystal X-ray diffraction. Both compounds are thermally stable and show no degradation in the presence of air or water. An in-depth echo-detected field-sweep (EDFS) ESR spectroscopic study in frozen solution at temperatures below 10 K revealed resolved hyperfine interactions with the spin-bearing <small><sup>51</sup></small>V nucleus, along with additional couplings to neighboring <small><sup>14</sup></small>N and <small><sup>1</sup></small>H nuclei detected in ESEEM experiments. Investigation of the spin dynamics, and of the potential influence of the distinct coordination geometries, yielded long spin-lattice relaxation times (<em>T</em><small><sub>1</sub></small>) exceeding 100 ms at 5 K, which decreased to about 40 µs at 50 K. These long <em>T</em><small><sub>1</sub></small> times therefore do not limit the spin coherence, and consequently the phase-memory times (<em>T</em><small><sub>m</sub></small>), at very low temperatures. The latter ranged from 5 to 8 µs and exhibited negligible temperature dependence within the investigated range. However, the use of a deuterated solvent increased <em>T</em><small><sub>m</sub></small> by approximately one order of magnitude to 52 µs at 5 K, though it also resulted in a more pronounced temperature dependence. Coherent spin manipulation was demonstrated by echo-detected transient nutation experiments, revealing well-defined Rabi oscillations with frequencies in the range of 13 MHz at an attenuation level of 9 dB and figures of merit exceeding 10<small><sup>3</sup></small> in deuterated solvent. Cluster correlation expansion (CCE) simulations reproduce the experimentally observed trends and identify the surrounding nuclear spin bath as the dominant decoherence source under dilution-limit conditions. No significant differences attributable to the distinct coordination geometries or structural variations in the ligand backbone were observed. These findings establish the present vanadium(IV) complexes as competitive candidates for molecular spin qubits and promising targets for future surface-deposition studies","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"159 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384162","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}
Julie Herniman, George Keeling, Rhys P. King, Navya Kandathil-Sintho, Mark E. Light, Kate Snowsill, Gillian Reid
Two new phosphine oxide appended aza-macrocyclic ligands, L1 and L3, have been prepared in good yield from the reaction of Bn-tacn and Bn-cyclen (tacn = 1,4,7-triazacyclononane; cyclen = 1,4,7,10-tetraazacyclododecane) with paraformaldehyde and diphenylphosphine oxide. They are characterised spectroscopically and via a crystal structure determination for L3·MeCN. The coordination chemistry of these ligands and the known NOTP-Ph (L2) with divalent late 3d metal ions, Co, Ni, Cu and Zn, has been investigated, showing that L1 and L2 bind in a pentadentate and hexadentate manner, respectively, in all cases. The potentially heptadentate L3 is found to coordinate to Co(II) and Zn(II) in a hexadentate manner (N4O2 donor set) giving distorted trigonal prismatic cations, and to Ni(II) through the same N4O2 donor set, but in a distorted octahedral geometry. These assignments follow from a combination of elemental analyses, mass spectrometry, IR, UV-visible, 1H and 31P{1H} NMR spectroscopic data, as appropriate, and X-ray crystal structures of several representative examples incorporating L1-L3. The properties of the new complexes are also compared to the literature data from the corresponding complexes of the cyclen macrocycle bearing four diphenylphosphine oxide pendant groups, DOTP-Ph, which are distinctly different. Overall, these studies across this series of ligands and metals demonstrate that the macrocyclic ring size, metal ion type and the number of pendant phosphine oxide arms all play an important role in determining the resulting coordination numbers and geometries.
{"title":"Transition metal complexes with phosphine oxide appended aza-macrocycles – effects of ring size and denticity","authors":"Julie Herniman, George Keeling, Rhys P. King, Navya Kandathil-Sintho, Mark E. Light, Kate Snowsill, Gillian Reid","doi":"10.1039/d6dt00255b","DOIUrl":"https://doi.org/10.1039/d6dt00255b","url":null,"abstract":"Two new phosphine oxide appended aza-macrocyclic ligands, L1 and L3, have been prepared in good yield from the reaction of Bn-tacn and Bn-cyclen (tacn = 1,4,7-triazacyclononane; cyclen = 1,4,7,10-tetraazacyclododecane) with paraformaldehyde and diphenylphosphine oxide. They are characterised spectroscopically and via a crystal structure determination for L3·MeCN. The coordination chemistry of these ligands and the known NOTP-Ph (L2) with divalent late 3d metal ions, Co, Ni, Cu and Zn, has been investigated, showing that L1 and L2 bind in a pentadentate and hexadentate manner, respectively, in all cases. The potentially heptadentate L3 is found to coordinate to Co(II) and Zn(II) in a hexadentate manner (N4O2 donor set) giving distorted trigonal prismatic cations, and to Ni(II) through the same N4O2 donor set, but in a distorted octahedral geometry. These assignments follow from a combination of elemental analyses, mass spectrometry, IR, UV-visible, 1H and 31P{1H} NMR spectroscopic data, as appropriate, and X-ray crystal structures of several representative examples incorporating L1-L3. The properties of the new complexes are also compared to the literature data from the corresponding complexes of the cyclen macrocycle bearing four diphenylphosphine oxide pendant groups, DOTP-Ph, which are distinctly different. Overall, these studies across this series of ligands and metals demonstrate that the macrocyclic ring size, metal ion type and the number of pendant phosphine oxide arms all play an important role in determining the resulting coordination numbers and geometries.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"59 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147447861","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}
Artem A Mikhailov,Axel Gansmüller,Asma Hasil,Sébastien Pillet,Gennadiy Kostin,Guillaume Chastanet,Theo Woike,Dominik Schaniel
Representative for the {MNO}8 series of metal-nitrosyl compounds, the neutral {CoNO}8 cobalt nitrosyl complex [Co(fpin)NO(phen)] (1) with fpin = perfluoropinacolate(2-) and phen = phenanthroline(0) exhibits a single photoinduced linkage isomer (PLI) that can be generated by irradiation with red light. The high population of 80% PLI enables the unambiguous determination of its structure as a bent κO isonitrosyl Co-O-N with a Co-O-N angle of 123.1(3)° compared to the bent κN nitrosyl Co-N-O ground state with an angle of 121.199(14)°. While the photoswitching in this diamagnetic {CoNO}8 complex is triggered by a metal-to-ligand charge transfer transition like in the well-known {MNO}6 complexes, the vibrational response is opposite, yielding a blue-shift of the N-O stretching vibration upon isonitrosyl PLI generation in {MNO}8 and a red-shift in {MNO}6. First-principles DFT calculations, performed on the photocrystallography models, provide results consistent with the observed structures and vibrational spectra. Additionally, the analysis of the Bader charges shows that the charge on the NO is more positive in the PLI compared to the GS for both the {MNO}8 and {MNO}6 complexes. Hence, the experimental vibrational spectra should not be directly used as sole evidence to derive underlying structures or electron density changes.
{"title":"NO photoswitches: a single photoinduced linkage isomer in diamagnetic {MNO}8 complexes.","authors":"Artem A Mikhailov,Axel Gansmüller,Asma Hasil,Sébastien Pillet,Gennadiy Kostin,Guillaume Chastanet,Theo Woike,Dominik Schaniel","doi":"10.1039/d6dt00116e","DOIUrl":"https://doi.org/10.1039/d6dt00116e","url":null,"abstract":"Representative for the {MNO}8 series of metal-nitrosyl compounds, the neutral {CoNO}8 cobalt nitrosyl complex [Co(fpin)NO(phen)] (1) with fpin = perfluoropinacolate(2-) and phen = phenanthroline(0) exhibits a single photoinduced linkage isomer (PLI) that can be generated by irradiation with red light. The high population of 80% PLI enables the unambiguous determination of its structure as a bent κO isonitrosyl Co-O-N with a Co-O-N angle of 123.1(3)° compared to the bent κN nitrosyl Co-N-O ground state with an angle of 121.199(14)°. While the photoswitching in this diamagnetic {CoNO}8 complex is triggered by a metal-to-ligand charge transfer transition like in the well-known {MNO}6 complexes, the vibrational response is opposite, yielding a blue-shift of the N-O stretching vibration upon isonitrosyl PLI generation in {MNO}8 and a red-shift in {MNO}6. First-principles DFT calculations, performed on the photocrystallography models, provide results consistent with the observed structures and vibrational spectra. Additionally, the analysis of the Bader charges shows that the charge on the NO is more positive in the PLI compared to the GS for both the {MNO}8 and {MNO}6 complexes. Hence, the experimental vibrational spectra should not be directly used as sole evidence to derive underlying structures or electron density changes.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"52 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147381401","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}
Vladimir V. Titkov, Egor Latipov, Oksana V. Baryshnikova, Fedor D. Fedyunin, Dina V. Deyneko, Bogdan Lazoryak
New anion-substituted vanadates Ca 9.75±δ Eu 0.5 (XO 4 ) 0.1 (VO 4 ) 6.9 (X = As 5+ , S 6+ , Sb 5+ , Ta 5+ , Mo 6+ , Te 4+ ) have been synthesized by high-temperature solid-state method. Crystal structure, nonlinear optical properties, photoluminescence excitation (PLE) and emission (PL) spectra are investigated. The maximum second harmonic generation (SHG) value is achieved for the compound with Te 4+ , where the intensity increases by 6 times. For all samples, the most intense luminescence band is in the region of 613.5 nm with excitation at 395 nm. The maximum luminescence intensity is observed for vanadate with Te 4+ , and the minimum for vanadate with Mo 6+ . The presence of at least two bands in the region of the 5 D 0 → 7 F 0 transition indicates low symmetry of Eu 3+ polyhedra, which occupy at least two positions in the structure. The CIE color coordinates for all compositions except the initial composition are poorly distinguishable. Experimental data show that Ca 9.75±δ Eu 0.5 (XO 4 ) 0.1 (VO 4 ) 6.9 phosphors are promising candidates for use in solid-state lighting.
采用高温固相法合成了新的阴离子取代钒酸盐Ca 9.75±δ Eu 0.5 (XO 4) 0.1 (VO 4) 6.9 （X = As 5+, S 6+, Sb 5+, Ta 5+, Mo 6+, Te 4+）。研究了晶体结构、非线性光学特性、光致发光激发（PLE）和发射（PL）光谱。含Te 4+的化合物的二次谐波产生（SHG）值达到最大值，强度增加了6倍。所有样品的发光波段都在613.5 nm区域，激发波长为395 nm。含te4 +的钒酸盐发光强度最大，含mo6 +的钒酸盐发光强度最小。在5d0→7f0跃迁区域至少存在两个能带，表明Eu 3+多面体的对称性较低，在结构中至少占据两个位置。除了初始成分外，所有成分的CIE颜色坐标都很难区分。实验数据表明，Ca 9.75±δ Eu 0.5 (XO 4) 0.1 (VO 4) 6.9荧光粉有望应用于固态照明。
{"title":"Influence of anionic substitutions on the nonlinear-optical and luminescent properties of Ca 9.75 Eu 0.5 (VO 4 ) 7","authors":"Vladimir V. Titkov, Egor Latipov, Oksana V. Baryshnikova, Fedor D. Fedyunin, Dina V. Deyneko, Bogdan Lazoryak","doi":"10.1039/d5dt02750k","DOIUrl":"https://doi.org/10.1039/d5dt02750k","url":null,"abstract":"New anion-substituted vanadates Ca 9.75±δ Eu 0.5 (XO 4 ) 0.1 (VO 4 ) 6.9 (X = As 5+ , S 6+ , Sb 5+ , Ta 5+ , Mo 6+ , Te 4+ ) have been synthesized by high-temperature solid-state method. Crystal structure, nonlinear optical properties, photoluminescence excitation (PLE) and emission (PL) spectra are investigated. The maximum second harmonic generation (SHG) value is achieved for the compound with Te 4+ , where the intensity increases by 6 times. For all samples, the most intense luminescence band is in the region of 613.5 nm with excitation at 395 nm. The maximum luminescence intensity is observed for vanadate with Te 4+ , and the minimum for vanadate with Mo 6+ . The presence of at least two bands in the region of the 5 D 0 → 7 F 0 transition indicates low symmetry of Eu 3+ polyhedra, which occupy at least two positions in the structure. The CIE color coordinates for all compositions except the initial composition are poorly distinguishable. Experimental data show that Ca 9.75±δ Eu 0.5 (XO 4 ) 0.1 (VO 4 ) 6.9 phosphors are promising candidates for use in solid-state lighting.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"101 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147384171","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}
The development of green and insensitive primary explosives to replace toxic heavy-metal-based energetic materials (e.g., lead azide) remains a central challenge in the field of modern energetic materials. This work presents a ligand engineering strategy based on site-specific N-methylation to regulate the energy–safety balance in copper perchlorate energetic coordination compounds. By systematically employing four N-methyl-1H-pyrazole-carbohydrazide ligands with distinct methyl substitution patterns (varying in position and number), a series of isostructural congeners (ECC-1 to ECC-4) with identical coordination motifs were successfully constructed, providing an ideal platform for structure–property relationship studies. Multidimensional mechanistic investigations revealed that methylation exerts a finely tuned influence: ortho-methylation enhances thermal stability (e.g., ECC-4, Td = 188 °C) primarily by strengthening coordination bonds through its electron-donating effect, whereas meta-methylation facilitates more uniform molecular surface charge distribution, optimizing the supramolecular interaction network and thereby significantly improving mechanical safety. Owing to its balanced methylation pattern, complex ECC-3 integrates low mechanical sensitivity (IS = 3.8 J, FS = 9 N), excellent laser ignition capability (El = 5 mJ), and reliable detonation performance, demonstrating the most promising overall practical potential. This study elucidates the feasibility of synergistically tuning properties at both molecular and supramolecular levels through rational ligand design, offering a new paradigm for developing high-performance and highly safe energetic materials.
{"title":"Position-Oriented N-Methylation Engineering: Multidimensional Regulation of Energy-Safety Balance in Energetic Copper Complexes","authors":"Chao Zhang, Tingwei Wang, Shaoqun Li, Zu-Jia Lu, Cong Li, Meiqi Xu, Binshan Zhao, Qiyao Yu, Jianguo Zhang","doi":"10.1039/d6dt00365f","DOIUrl":"https://doi.org/10.1039/d6dt00365f","url":null,"abstract":"The development of green and insensitive primary explosives to replace toxic heavy-metal-based energetic materials (e.g., lead azide) remains a central challenge in the field of modern energetic materials. This work presents a ligand engineering strategy based on site-specific N-methylation to regulate the energy–safety balance in copper perchlorate energetic coordination compounds. By systematically employing four N-methyl-1H-pyrazole-carbohydrazide ligands with distinct methyl substitution patterns (varying in position and number), a series of isostructural congeners (ECC-1 to ECC-4) with identical coordination motifs were successfully constructed, providing an ideal platform for structure–property relationship studies. Multidimensional mechanistic investigations revealed that methylation exerts a finely tuned influence: ortho-methylation enhances thermal stability (e.g., ECC-4, Td = 188 °C) primarily by strengthening coordination bonds through its electron-donating effect, whereas meta-methylation facilitates more uniform molecular surface charge distribution, optimizing the supramolecular interaction network and thereby significantly improving mechanical safety. Owing to its balanced methylation pattern, complex ECC-3 integrates low mechanical sensitivity (IS = 3.8 J, FS = 9 N), excellent laser ignition capability (El = 5 mJ), and reliable detonation performance, demonstrating the most promising overall practical potential. This study elucidates the feasibility of synergistically tuning properties at both molecular and supramolecular levels through rational ligand design, offering a new paradigm for developing high-performance and highly safe energetic materials.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"17 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147381060","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}
Gunasekaran Arunkumar, Monisha Arumugam, Mariappan Mariappan, B Anna Benedict, Savarimuthu Philip Anthony
The electrocatalytic water splitting activity of metal organic frameworks (MOFs) is optimized/enhanced by tailoring the coordination environments and fabricating composites with conducting materials. Herein, a water coordinated copper (Cu) MOF was synthesized using monosodium glutamate (MSG) and improved its bifunctional electrocatalytic activity in alkaline medium by integrating conducting rGO. Single crystal structural analysis confirmed the formation of 3D network structure with a water coordination and a lattice water molecule. Electrocatalytic studies of CuMSG showed relatively weak activity both in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). It required 381 and 408 mV to achieve 20 mA/cm2 current density, respectively. However, the electrocatalytic activity of CuMSG was strongly enhanced by fabricating composite with conducting rGO. CuMSG/rGO 250 and 280 mV to produce the 20 mA/cm2 current density. The low Tafel slope of CuMSG/rGO (128 (HER) and 48 mV/dec (OER)) compared to CuMSG (170 (HER) and 75 mV/dec (OER)) indicated improved kinetics at the electrode-catalyst interface after combining with conducting rGO. The integration rGO with CuMSG also reduced the charge transfer resistance (2.86 (HER) and 3.38 Ohm (OER)), which also contributed for enhanced bifunctional electrocatalytic activity. The bifunctional electrocatalytic activity of CuMSG-rGO was utilized for overall water splitting and required the cell potential of 1.72 V to achieve the 10 mA/cm2 current density. CuMSG-rGO electrocatalyst displayed good stability over 20h in OER, HER as well as overall water splitting.
{"title":"Enhancing bifunctional and overall water splitting electrocatalytic activity copper MOF by integrating conducting rGO","authors":"Gunasekaran Arunkumar, Monisha Arumugam, Mariappan Mariappan, B Anna Benedict, Savarimuthu Philip Anthony","doi":"10.1039/d5dt02903a","DOIUrl":"https://doi.org/10.1039/d5dt02903a","url":null,"abstract":"The electrocatalytic water splitting activity of metal organic frameworks (MOFs) is optimized/enhanced by tailoring the coordination environments and fabricating composites with conducting materials. Herein, a water coordinated copper (Cu) MOF was synthesized using monosodium glutamate (MSG) and improved its bifunctional electrocatalytic activity in alkaline medium by integrating conducting rGO. Single crystal structural analysis confirmed the formation of 3D network structure with a water coordination and a lattice water molecule. Electrocatalytic studies of CuMSG showed relatively weak activity both in hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). It required 381 and 408 mV to achieve 20 mA/cm2 current density, respectively. However, the electrocatalytic activity of CuMSG was strongly enhanced by fabricating composite with conducting rGO. CuMSG/rGO 250 and 280 mV to produce the 20 mA/cm2 current density. The low Tafel slope of CuMSG/rGO (128 (HER) and 48 mV/dec (OER)) compared to CuMSG (170 (HER) and 75 mV/dec (OER)) indicated improved kinetics at the electrode-catalyst interface after combining with conducting rGO. The integration rGO with CuMSG also reduced the charge transfer resistance (2.86 (HER) and 3.38 Ohm (OER)), which also contributed for enhanced bifunctional electrocatalytic activity. The bifunctional electrocatalytic activity of CuMSG-rGO was utilized for overall water splitting and required the cell potential of 1.72 V to achieve the 10 mA/cm2 current density. CuMSG-rGO electrocatalyst displayed good stability over 20h in OER, HER as well as overall water splitting.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"40 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147381062","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}
Michael Thomas Thoenen, Aleska Milosavljevic, Davin Piercey, Paul Wenthold
Nitrilimines are a useful chemical intermediate for the synthesis of a variety of nitrogen heterocycles for use in pharmaceuticals, energetics, and other energy storage applications. The limitations of this intermediate are explored here with a paired experimental and computational study into the viable substituents for its generation from 2,5-substituted tetrazoles. Nitrilimines generated via the loss of nitrogen gas from these tetrazoles are possible with almost any substitution at the 5-position, with electron withdrawing groups aiding in formation. The lack of an aryl or heteroaryl substituent at the 2-position of the tetrazole prevented nitrilimine formation in all experiments, an observation that was supported by computation.
{"title":"Combined Computational and Experimental Study on Nitrilimines Generated from 2,5-Substituted Tetrazoles","authors":"Michael Thomas Thoenen, Aleska Milosavljevic, Davin Piercey, Paul Wenthold","doi":"10.1039/d6dt00045b","DOIUrl":"https://doi.org/10.1039/d6dt00045b","url":null,"abstract":"Nitrilimines are a useful chemical intermediate for the synthesis of a variety of nitrogen heterocycles for use in pharmaceuticals, energetics, and other energy storage applications. The limitations of this intermediate are explored here with a paired experimental and computational study into the viable substituents for its generation from 2,5-substituted tetrazoles. Nitrilimines generated via the loss of nitrogen gas from these tetrazoles are possible with almost any substitution at the 5-position, with electron withdrawing groups aiding in formation. The lack of an aryl or heteroaryl substituent at the 2-position of the tetrazole prevented nitrilimine formation in all experiments, an observation that was supported by computation.","PeriodicalId":71,"journal":{"name":"Dalton Transactions","volume":"53 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147383885","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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