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Developing suitable electrode materials for sodium-ion batteries (SIBs) is important to improve the electrochemical performance. Herein, we prepare n-type carbonaceous anodes via pyrolysis of naphthol-functionalized polytriarylamine that manifests rapid Na+ storage. During pyrolysis, gas evolution from poly(DNap-OH) triggers structural rearrangement to form a disordered microstructure with a high char-yield of 72%. When utilizing PDNOH as anodes in SIBs, PDNOH-800 delivered the specific capacity of 212 mA h g−1 at 0.05 A g−1 and stable cycling behavior with C.E. of 99.7%. The n-type characteristics attributed to N- and O-moieties played a critical role to enhance the electrochemical performance of SIBs via surface-induced Na+ storage with fast kinetics. [ABSTRACT FROM AUTHOR]

We report a new strategy, namely solvent-assisted curing, for developing a porous network into polymeric materials. A simple thermal process for nonporous melamine formaldehyde polymers in aprotic solvents affords porous characteristics with an exceptionally high surface area, resulting from the swelling and exclusion of a part of the polymeric structure aided by the solvent. The porous properties can be determined by selecting solvents and the monomer ratio that affects the degree of crosslinking. Furthermore, by tailoring the shape of precursor materials, we prepared the porous polymer in a variety of forms, such as particles and a monolith. The resulting material was exploited for CO2 adsorption and proved to be a potential gas sorbent. This versatile approach can be combined with other polymeric materials and provides an approach toward expanding the range of porous materials. [ABSTRACT FROM AUTHOR]

We synthesized a new poly(triphenylamine), having a hyperbranched structure, and employed it in lithium-ion batteries as an organic cathode material. Two types of monomers were prepared with hydroxyl groups and nitro leaving groups, activated by a trifluoromethyl substituent, and then polymerized via the nucleophilic aromatic substitution reaction. The reactivity of the monomers differed depending on the number of hydroxyl groups and the A2B type monomer with one hydroxyl group successfully produced poly(triphenylamine). Based on thermal, optical, and electrochemical analyses, a composite poly(triphenylamine) electrode was made. The electrochemical performance investigations confirmed that the lithium-ion batteries, fabricated with the poly(triphenylamine)-based cathodes, had reasonable specific capacity values and stable cycling performance, suggesting the potential of this hyperbranched polymer in cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]