We report a simple one-pot method for transforming commercial PC61BM into a variety of functional fullerene derivatives with tunable properties, such as compounds with oligo(ethylene glycol) or alkyl ester side chains. The proposed approach bypasses multistep synthesis, greatly simplifies access to diverse fullerene derivatives, and provides a practical platform for the rational design of optoelectronic and biomedical materials.

Interaction of fullerene C60 with Cs2Fe(CO)4 in the presence of two equivalents of tetrabutylammonium iodide (TBAI) yields the first dianionic coordination complex of fullerene: (TBA+)2{[Fe2(CO)6]-η2,η2-C60}2- (1). According to magnetic data and DFT calculations, complex 1 has a diamagnetic ground (S = 0) and a triplet excited state (S = 1) populated above 80 K. As a result, a new broad EPR signal appears, whose integral intensity grows with temperature; the estimated singlet-triplet energy gap is 508 ± 8 K. The broad signal attributed to the triplet has g = 2.0046 with a line width of 5.6 mT at 140 K, and this signal is shifted to smaller g-factors (2.0000) and narrows as the temperature increases. Calculations also show that the singlet-triplet gap is defined by the positions of the cations close to the Fe2(CO)6 fragment or the fullerene cage. According to DFT calculations, the negative electron density is mainly localized on the fullerene cage (-1.051) in the singlet state, and this charge even increases to -1.204 in the triplet state of the complex. Spin density localized on Fe2(CO)6 is concentrated on only one of the two iron atoms.

Mono-and binuclear complexes of FeII and CoII with deprotonated trans-indigo were obtained. Reduction of indigo by metallic iron in the presence of crystal violet (CV) yields (CV+)[(FeCl2)HIndigo]- & sdot;C6H4Cl2 (1). The reaction of FeI2 and CoI2 with one equivalent of decamethylchromocene (Cp*2Cr) and one or half equivalent of indigo yields mononuclear (Cp*2Cr+)[(CoI2)HIndigo]- & sdot;C6H4Cl2 (2), (Cp*2Cr+)[(FeI2)HIndigo]-& sdot; xC6H4Cl2, where x = 1 (3) or 0.5 (4), and binuclear (Cp*2Cr+)2[(CoI2)2Indigo]2-& sdot;4C6H4Cl2 (7) complexes. Interaction of indigo with CoI2 in the presence of TBAI yields complex (TBA+)2[(CoI2)2Indigo]2-(5), while its reduction by potassium graphite with Cryptand[2.2.2] and CoI2 affords complex {(K+)Cryptand[2.2.2]}2[(CoI2)2Indi-go]2-& sdot;2C6H4Cl2 (6). As a result, coordination units of indigo were obtained in different cationic surroundings allowing us to study how these cations affect magnetic exchange in the binuclear complexes. The most intense absorption band of indigo (665 nm) is red-shifted to 706-740 nm for mononuclear and 860-878 nm for binuclear complexes. The lowest energy bands observed at 1060 and 1376-1400 nm are primarily attributed to metal-toligand charge transfer. Short N-Co (1.944(4) & Aring;) and O-Co bonds (1.951(5) & Aring;) are observed in 5 with the TBA+ cations but these bonds are elongated to 1.968(3) & Aring; and 1.970(4) & Aring;, respectively, in 6 with the {(K+)Cryptand [2.2.2]} cations which are inserted between the CoI2 fragments. Ferromagnetic coupling is found in the {[(FeCl2) HIndigo]-}2 dimers of 1, providing parallel alignment of the FeII (S = 2) spins within the dimers at low temperatures. Weak magnetic coupling between FeII (S = 2) and CrIII (S = 3/2) spins is found in 3 that is explained by large spatial separation between magnetic centers. Magnetic exchange values between two high-spin CoII ions (S = 3/2) in the [(CoI2)2Indigo]2-dianions (5 and 6) depend on bond lengths. Shorter Co-N and Co-O bonds in 5 provide substantial antiferromagnetic coupling between the CoII spins (J =-7.40 cm-1), and as a result, these dianions transfer to a diamagnetic state at low temperatures. Longer Co-N(O) bonds in 6 weaken coupling, which can be described as averaged interaction with Jinter =-0.33 cm-1. As a result, variation of cationic surrounding affects intramolecular coupling between the CoII spins through the diamagnetic Indigo2-dianions.

Potassium-sulfur (K-S) batteries have emerged as an ideal candidate for large-scale energy storage because of the high theoretical energy density and low material cost. However, the practical deployment of K-S batteries is impeded by challenges such as polysulfide shuttling, sluggish conversion kinetics, and interfacial instability. Despite extensive experimental work in materials development, the underlying mechanisms at the atomic and molecular levels remain poorly understood. Computational methods have proven useful for elucidating K-S electrochemistry from a microscopic perspective. Nevertheless, a comprehensive review that systematically combines these experimental advances with computational insights is still lacking. To address this gap, this review provides a comprehensive overview of advances in K-S battery research, with emphasis on the materials engineering and computational research. We first summarize the fundamental mechanisms of K-S batteries and progress in key battery components including cathode, anode, electrolyte, as well as binder and separator. Complementing these experimental efforts, we introduce the theoretical foundations of density functional theory and molecular dynamics simulations, and review their recent applications in critical aspects such as adsorption energetics, reaction kinetics, electronic properties, and dynamic behaviors. Finally, we outline future directions for K-S battery research, including the integration of advanced characterization with multi-scale simulation, the development of high-throughput experimental and computational platforms, and the application of artificial intelligence to accelerate the development of materials and computational simulations. This review aims to provide guidance for the rational design of high-performance K-S battery systems by integrating experimental and theoretical insights.

A novel organic cathode enables high-performance K-ion batteries, delivering 350 mA h g −1 and exceptional stability for over 600 cycles. Its key advantage is retaining 73% capacity at −50 °C, where conventional cathodes fail.

The attempted substitution of Cl atoms in C60Cl6 with nucleophiles formed in situ from 1,3-dicarbonyl compounds and potassium carbonate led to the realization of a highly unexpected pathway that produced fullerene derivatives with dihydrofuran rings fused to the fullerene cage. The major products incorporated two dihydrofuran addends attached to the C60 cage at cis-1 and cis-2 positions, while other regioisomers were not observed. Thus, the critical problem of the selective addition of two cyclic organic addends to the fullerene cage was successfully mitigated in such an extraordinary way involving C60Cl6 as a substrate. The presented findings demonstrate the potential of using halofullerenes as templated substrates in common fullerene reactions (cyclopropanation, cycloaddition, etc.) to enhance their selectivity.

The structure of symmetrical thiolate cluster Au25(SR)18 becomes asymmetrical after the removal of all bridging S*R groups from the six staple fragments (SR)Au(S*R)Au(SR). This is accompanied by the formation of new Au3 and Au4 active sites.

The interaction of ring-reduced free-base tetra(4-pyridyl)porphyrin (H2TPyP) and its copper(ii) complex with an excess of MIII(TMHD)3 (TMHD = 2,2,6,6-tetramethyl-3,5-heptanedionate) affords a new type of coordination polymer in which lanthanide ions are bridged by porphyrin anions. Unusual folded zig-zag 2D coordination polymers, {Cryptand(K+)}n{H2TPyP & centerdot;[DyIII(TMHD)3]2-}n & centerdot;3n(C6H14) (1) and {Cryptand(Cs+)}n{CuIITPyP & centerdot;[TbIII(TMHD)3]2-}n & centerdot;3n(C6H5CH3)& centerdot; 1.5n(C6H14) (2), contain paramagnetic singly reduced porphyrin ligands. 1D linear coordination polymers, {Cryptand(Cs+)}2n{H2TPyP & centerdot;[TbIII(TMHD)3]22-}n & centerdot;3n(C6H5CH3) (3) and the isostructural {Cryptand(Cs+)}2n{H2TPyP & centerdot;[GdIII(TMHD)3]22-}n & centerdot;3n(C6H5CH3) (4), contain diamagnetic doubly reduced porphyrin ligands. Each MIII(TMHD)3 unit forms MIII-N(Py) coordination bonds (2.58-2.67 & Aring;) with two porphyrins, resulting in a distorted square-antiprismatic coordination environment around the MIII ions. The folded zig-zag 2D polymers exhibit dihedral angles between porphyrin planes of 53.1-53.8 degrees in compounds 1 and 2. These folds arise from the insertion of {Cryptand(M+)} cations between the porphyrin planes. In contrast, two such cations surround each porphyrin in compound 3, leading to the formation of a linear 1D polymer. The Cs+ ions are displaced from the cryptand cavity toward the porphyrin core, forming short Cs+-N(TPyP) contacts of 3.2-3.3 & Aring;. Optical spectra confirm the formation of ring-reduced H2TPyP(center dot)- and TPyP(center dot)3- species in 1 and 2, whereas new bands attributed to H2TPyP2- dianions appear in the spectra of 3 and 4. Magnetic measurements suggest weak antiferromagnetic coupling in the 2D polymers of 1 and 2 mediated by paramagnetic porphyrin bridges. DFT calculations indicate weak localization of spin density on the nitrogen atoms of two of the four pyridyl rings due to their rotation relative to the porphyrin plane by 58.6-84.5 degrees. The GdIII centers are separated by diamagnetic H2TPyP2- bridges in the linear polymers of 4, providing zero metal-metal magnetic coupling with small zero-field splitting.

An additive approach for determining the activation energies of thermoneutral reactions is presented, which makes it possible to find the rate constants of radical reactions of H atom abstraction based on the enthalpy of these reactions and the rate constants of the corresponding symmetric reactions.

A redox-active tetrapyrazinoporphyrazine ligand was used as a platform for the design of multimetallic coordination complexes. The first paramagnetic homo- and heterotrimetallic complexes have been obtained as crystals through the reaction of iron(II) octaethyltetrapyrazinoporphyrazine, FeII(Et8TPyzPz), with 3d- (FeII, CoII) and 4f-metal (DyIII) iodides. In these conditions, tetrapyrazinoporphyrazine can coordinate to metals to form exo- and endocyclic complexes when coordination is observed both in the center and on the periphery of a macrocycle. Crystal structures of the complexes have been determined from single-crystal X-ray diffraction analysis, and their compositions are {TBA+}2[FeIII2(Et8TPyzPz)& centerdot;(FeIII2)2]2- (1), {TBA+}2[FeIII2(Et8TPyzPz)& centerdot;(CoIII2)2]2- (2), and {TBA+}2[FeIII2(Et8TPyzPz)& centerdot;(DyIIII3)2]2- & centerdot;4C6H4Cl2 (3). The central iron(II) atom forms four shorter N-Fe bonds (1.917(3)-1.927(3) & Aring;) and two longer I-Fe bonds (2.68 & Aring;).Two exocyclic metal iodides are coordinated to the periphery of the Et8TPyzPz macrocycle. The iron(II) and cobalt(II) atoms are tetracoordinated when inserted into the N2-pockets to form both M-Nmeso and M-Npyrazine bonds of 2.14 and 2.24 & Aring; for Fe(II) and 2.10 and 2.16 & Aring; for Co(II), respectively. The exocyclic Dy ions, when introduced into the N3-pockets to form the Dy-N bonds of 2.43 and 2.66-2.75 & Aring;, respectively, have distorted octahedral geometry. Optical and magnetic properties of the solids were investigated. The [FeIII2(Et8TPyzPz)2-& centerdot;(MI x )2]2- units contain a low-spin diamagnetic central Fe(II) ion and high-spin exocyclic FeII, CoII, and DyIII nuclei. Exocoordinated metal ions are antiferromagnetically coupled through the diamagnetic {FeIII2(Et8TPyzPz)}2- unit. The Soret and the Q-bands are observed in the spectra of starting {FeII(Et8TPyzPz)} and complexes 1-3 at 336-348and 645-655nm, supporting preservation of the Et8TPyzPz2- macrocycle at complex formation. At the same time, broad and intense bands appear at 495-526 nm in the visible range, and lower-energy bands are observed near the Q-band at 700 nm. The latter bands can be attributed to metal-to-macrocycle charge transfer (CT) in 1-3. CT is supported by DFT calculations.

A family of novel naphthalene benzimidazole (NBI)-based materials with different molecular weights was prepared by condensing 1,4,5,8-naphthalenetetracarboxylic dianhydride with 2,3-diaminophenazine, 2,3,7,8-tetraaminophenazine or their mixture. Of these materials, only intermediate molecular weight NBI provides high specific discharge capacity and exhibits good cycling stability and rate capability in potassium cells, while polymeric NBI also demonstrated decent performance in lithium cells. The results suggest a new approach for further rational design of NBI materials for metal-ion batteries with improved performance.

An advanced organic electrode material based on 5,6,11,12,17,18-hexaazatrinaphthylene (HATN) was synthesized. The developed poly-HATN demonstrated exceptional promise for potassium-ion batteries, exhibiting a stable discharge capacity of 150 mAh g−1 and a near-perfect Coulombic efficiency of approximately 100

We have designed an electrolyte composition capable of delayed self-polymerization by combining two commonly used electrolytes: 1 M LiTFSI in 1,3-dioxolane/1,2-dimethoxyethane and 1 M LiPF6 in ethylene carbonate/dimethyl carbonate. It has been shown that LiPF6 initiates self-polymerization of 1,3-dioxolane also involving dimethoxyethane molecules, which produces quasi solid (gel) electrolyte at the desired timescale after cell fabrication. This approach solves numerous technical issues such as poor adhesion of the solidified polymer electrolyte to the electrodes, incomplete soaking of the separator membrane, etc. Furthermore, we have serendipitously discovered that a new electrolyte formulation produces a specific solid electrolyte interface (SEI) on the lithium surface, which is beneficial for the battery operation. The advantages of the developed strategy have been demonstrated in batteries with an organic cathode and Li metal anode. While polythiopyranoquinone cathodes provided low capacities of similar to 90 mA h g-1 in LiTFSI and LiPF6-based commercial liquid electrolytes when they were used separately, the engineered self-polymerizable electrolyte enabled a high reversible specific capacity of 342 mA h g-1 with a capacity retention of 98.4% after 180 cycles. The observed improvement was due to the gelation of the electrolyte suppressing the dissolution of the organic electrode and also the formation of an optimal solid-electrolyte interface.

New low-temperature gelled electrolytes based on 1 M LiN(SO2CF3)2 in mixed solutions of glymes and 1,3-dioxolane with the addition of 1 wt.

This study demonstrates how an interaction between the additive BrFBN and a perovskite precursor results in a perovskite film with fewer defect states. This work provides insights on the feasibility of manufacturing stable, high-performance PSCs.

Interaction of {Cryptand(K+)}(C60 center dot-) with CpCo(CO)2 yields the air-sensitive crystalline salt {Cryptand(K+)}{CpCo(CO)-eta 2-C60 center dot-} (1), in which C60 center dot- replaces carbonyl group in CpCo(CO)2. Two Co-C bonds of 2.028(9) and 2.057(8)& Aring; are formed. The magnetic moment of 1 is 1.72 mu B, indicating a doublet S = 1/2 spin state of {CpCo(CO)-eta 2-C60 center dot-} at 300 K. The compound shows a broad EPR signal at g = 2.0000 with a line width of 3.93 mT (295 K), characteristic of C60 center dot-, confirming spin and electron density localization on the fullerene cage. This is the first coordination complex of a transition metal with C60 center dot-. Below 220 K, {CpCo(CO)-eta 2-C60 center dot-} dimerizes to form diamagnetic singly bonded {CpCo(CO)-eta 2-C60 -}2 dimers. Carbon atoms of the [6,6,5] junctions form an intercage single C-C bond of 1.619(18)& Aring;. Dimerization elongates the Co-C bonds to 2.098(13) and 2.106(13)& Aring;. Approximately 20% of S = 1/2 spins remain after dimerization indicating partial preservation of the paramagnetic monomeric phase. Coordination of C60 center dot- to CpCoCO becomes asymmetric in this phase, with shorter and longer Co-C bonds of 2.012(14) and 2.262(14) & Aring;, converting the eta 2-type to eta -type coordination. Dimerization is partially suppressed owing to the formation of densely packed C60 center dot- chains, where radical anions align hexagon-over-hexagon in parallel with close interplanar distances.

Herein, we address the problem of complicated synthesis and high cost of organic cathode materials for metal-ion batteries by utilizing the strategy of pyrolytic conversion of simple organic precursor molecules to redox-active polymers. As such, a well-known organic oxidation reagent DDQ was converted to the poly-DDQ, which demonstrated promising electrochemical characteristics as cathode in potassium cells: specific capacity reached 140-175 mAh g(-1) even at high current density, which is comparable to the emerging inorganic cathodes for potassium-ion batteries. Furthermore, the potassium cells with poly-DDQ cathodes demonstrated excellent cyclability due to the robust structure of the material prepared by high-temperature synthesis. The proposed approach to the scalable and low-cost synthesis of electrode materials by pyrolysis of readily available precursors appears to be highly promising in the context of practical applications, particularly for the stationary energy storage, where the cost of the battery and its cycle lifetime represent the most important parameters.