0000000000999336

AUTHOR

Lauri Kivijärvi

Simultaneous Endo- and Exo-Complex Formation of Pyridine[4]arene Dimer with Neutral and Anionic Guests

The formation of complexes between hexafluorophosphate (PF6−) and tetraisobutyloctahydroxypyridine[4]arene has been thoroughly studied in the gas phase (ESI‐QTOF‐MS, IM‐MS, DFT calculations), in the solid state (X‐ray crystallography), and in chloroform solution (1H, 19F, and DOSY NMR spectroscopy). In all states of matter, simultaneous endo complexation of solvent molecules and exo complexation of a PF6− anion within a pyridine[4]arene dimer was observed. While similar ternary complexes are often observed in the solid state, this is a unique example of such behavior in the gas phase. peerReviewed

research product

Considering lithium-ion battery 3D-printing via thermoplastic material extrusion and polymer powder bed fusion

Abstract In this paper, the ability to 3D print lithium-ion batteries through Pmnbspace thermoplastic material extrusion and polymer powder bed fusion is considered. Focused on the formulation of positive electrodes composed of polypropylene, LiFePO4 as active material, and conductive additives, advantages and drawbacks of both additive manufacturing technologies, are thoroughly discussed from the electrochemical, electrical, morphological and mechanical perspectives. Based on these preliminary results, strategies to further optimize the electrochemical performances are proposed. Through a comprehensive modeling study, the enhanced electrochemical suitability at high current densities of va…

research product

Simultane endo - und exo -Komplexbildung von Pyridin[4]aren-Dimeren mit neutralen und anionischen Gästen

research product

Electrochemical properties of graphite/nylon electrodes additively manufactured by laser powder bed fusion

Nowadays, additive manufacturing, known as 3D printing, is vigorously employed at various enterprises due to the ability of industrial series production and customization in conjunction with geometry freedom. While, material design and fabrication of composite materials, meeting the desired architecture and properties, is another promising application of additive manufacturing. For instance, additive manufacturing of the material exhibiting electrochemical properties is beneficial for the development of freestanding electrodes that might be used in electrochemical energy storage systems. Herein, the graphite/nylon composite with a high carbon ratio of 30 wt% was produced by laser powder bed…

research product

Selective recovery of gold from electronic waste using 3D-printed scavenger

Around 10% of the worldwide annual production of gold is used for manufacturing of electronic devices. According to the European Commission, waste electric and electronic equipment is the fastest growing waste stream in the European Union. This has generated the need for an effective method to recover gold from electronic waste. Here, we report a simple, effective, and highly selective nylon-12-based three-dimensional (3D)-printed scavenger objects for gold recovery directly from an aqua regia extract of a printed circuit board waste. Using the easy to handle and reusable 3D-printed meshes or columns, gold can be selectively captured both in a batch and continuous flow processes by dipping …

research product

3D Printed Palladium Catalyst for Suzuki-Miyaura Cross-coupling Reactions

Selective laser sintering (SLS) 3d printing was utilized to manufacture a solid catalyst for Suzuki-Miyaura cross-coupling reactions from polypropylene as a base material and palladium nanoparticles on silica (SilicaCat Pd(0)R815-100 by SiliCycle) as the catalytically active additive. The 3d printed catalyst showed similar activity to that of the pristine powdery commercial catalyst, but with improved practical recoverability and reduced leaching of palladium into solution. Recycling of the printed catalyst led to increase of the induction period of the reactions, attributed to the pseudo-homogeneous catalysis. The reaction is initiated by oxidative addition of aryl iodide to palladium nano…

research product

Preparation of Highly Porous Carbonous Electrodes by Selective Laser Sintering

Selective laser sintering (SLS) 3D printing was utilized to fabricate highly porous carbonous electrodes. The electrodes were prepared by using a mixture of fine graphite powder and either polyamide-12, polystyrene, or polyurethane polymer powder as SLS printing material. During the printing process the graphite powder was dispersed uniformly on the supporting polymer matrix. Graphite’s concentration in the mixture was varied between 5 and 40 wt % to find the correlation between the carbon content and conductivity. The graphite concentration, polymer matrix, and printing conditions all had an impact on the final conductivity. Due to the SLS printing technique, all the 3D printed electrodes …

research product

Considering lithium-ion battery 3D-printing via thermoplastic material extrusion and polymer powder bed fusion

In this paper, the ability to 3D print lithium-ion batteries through thermoplastic material extrusion and polymer powder bed fusion is considered. Focused on the formulation of positive electrodes composed of polypropylene, LiFePO4 as active material, and conductive additives, advantages and drawbacks of both additive manufacturing technologies, are thoroughly discussed from the electrochemical, electrical, morphological and mechanical perspectives. Based on these preliminary results, strategies to further optimize the electrochemical performances are proposed. Through a comprehensive modeling study, the enhanced electrochemical suitability at high current densities of various complex three…

research product

Crystal structure of the borabenzene–2,6-lutidine adduct

In the title compound, C12H14BN, the complete molecule is generated by a crystallographic twofold axis, with two C atoms, the B atom and the N atom lying on the rotation axis. The dihedral angle between the borabenzene and pyridine rings is 81.20 (6)°. As well as dative electron donation from the N atom to the B atom [B—N = 1.5659 (18) Å], the methyl substituents on the lutidine ring shield the B atom, which further stabilizes the molecule. In the crystal, weak aromatic π–π stacking between the pyridine rings [centroid–centroid separation = 3.6268 (9) Å] is observed, which generates [001] columns of molecules.

research product

Simultaneous endo and exo  Complex Formation of Pyridine[4]arene Dimers with Neutral and Anionic Guests

The formation of complexes between hexafluorophosphate (PF6- ) and tetraisobutyloctahydroxypyridine[4]arene has been thoroughly studied in the gas phase (ESI-QTOF-MS, IM-MS, DFT calculations), in the solid state (X-ray crystallography), and in chloroform solution (1 H, 19 F, and DOSY NMR spectroscopy). In all states of matter, simultaneous endo complexation of solvent molecules and exo complexation of a PF6- anion within a pyridine[4]arene dimer was observed. While similar ternary complexes are often observed in the solid state, this is a unique example of such behavior in the gas phase.

research product

CCDC 1543476: Experimental Crystal Structure Determination

Related Article: Anniina Kiesilä, Lauri Kivijärvi, Ngong Kodiah Beyeh, Jani O. Moilanen, Michael Groessl, Tatiana Rothe, Sven Götz, Filip Topić, Kari Rissanen, Arne Lützen and Elina Kalenius|2017|Angew.Chem.,Int.Ed.|56|10942|doi:10.1002/anie.201704054

research product