54812-36-1

Upstream product

• 2892-51-5 squaric acid 

Relevant academic research and scientific papers

Oxocarbon Salts for Fast Rechargeable Batteries

Oxocarbon salts (M2(CO)n) prepared through one-pot proton exchange reactions with different metal ions (M=Li, Na, K) and frameworks (n=4, 5, 6) have been rationally designed and used as electrodes in rechargeable Li, Na, and K-ion batteries. The results show that M2(CO)5/M2(CO)6salts can insert two or four metal ions reversibly, while M2(CO)4shows less electrochemical activity. Especially, we discover that the K2C6O6electrode enables ultrafast potassium-ion insertion/extraction with 212 mA h g?1at 0.2 C and 164 mA h g?1at 10 C. This behavior can be ascribed to the natural semiconductor property of K2C6O6with a narrow band gap close to 0.9 eV, the high ionic conductivity of the K-ion electrolyte, and the facilitated K-ion diffusion process. Moreover, a first example of a K-ion battery with a rocking-chair reaction mechanism of K2C6O6as cathode and K4C6O6as anode is introduced, displaying an operation voltage of 1.1 V and an energy density of 35 Wh kg?1. This work provides an interesting strategy for constructing rapid K-ion batteries with renewable and abundant potassium materials.

Vibrational spectroscopy and aromaticity investigation of squarate salts: A theoretical and experimental approach

Experimental and theoretical investigations of squarate salts [M2(C4O4)] (M=Li, Na, K and Rb) were performed aiming to correlate the structures, vibrational analysis and aromaticity. Powder X-ray diffraction data show that these compounds are not isostructural, indicating that the metal-squarate and hydrogen bonds to water molecules interactions play a significant role on the the crystal packing. The infrared and Raman assigments suggest an equalization of the C-C bond lengths with the increasing of the counter-ion size. This result is interpreted as an enhancement in the electronic delocalization and consequently in the degree of aromaticity for salts with larger ions. Quantum mechanical calculations for structures, vibrational spectra and aromaticity index are in agreement with experimental finding, giving insights at molecular level for the role played by distinct complexation modes to the observed properties. Comparison between our results and literature, regarding molecular dynamics in different chemical environments, shows that aromaticity and hydrogen bonds are the most important forces driving the interactions in the solid structures of squarate ion.