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We proved that ice crystallized from water molecules within as-synthesized graphene oxide (GO) can be used as a spacer among individual GO sheets to form an expanded GO aerogel with a three-dimensional porous network structure. This designed specific structure can be retained during further processes to form graphene paper. Due to the fact that the as-fabricated graphene paper contains carbon defects and space in its infrastructure, this creates more electroactive surfaces and interfaces to significantly increase the Faradaic reaction efficiency. With the introduction of redox-electrolyte K3Fe(CN)6 into a KOH electrolyte, we can obtain a 95-fold increase in the specific capacitance compared with the value obtained in the traditional KOH electrolyte. The ice-crystallization formed graphene paper electrode showed high electroactivity because the specific porous structure can favor the fast transfer of electrolyte ions, such as Fe(CN)63- ions. The presented results prove that ice-crystallization formed GO can serve as a chemically tunable platform for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]

Here we report a study on controlling the shape of particles by regulating the diffusion of chemicals. To change the diffusion rate of the reactive ions, we used a designed three-cell reactor in which the reactive ions were separated by porous membranes. We studied the reduction of hexachloroplatinate ions by sodium borohydride as an example. The experimental results show that control of the chemical diffusion led to the platinum product changing from cubic particles to dendritic particles. Further analysis indicates that the cubic particles were formed by the classic crystallization process via layer-wise deposition, while the dendritic particles were formed by the non-classic crystallization process through cluster aggregation. The control over the chemical diffusion prolongs the nucleation period and produces nuclei continuously, facilitating the aggregation of nuclei, which leads to the crystallization switching from the classic model to the non-classic model. The obtained results in this paper suggest that control over the chemical diffusion is a green and promising process to manipulate the structures of materials. [ABSTRACT FROM AUTHOR]

In this paper, we have built up the organic-inorganic hybrid co-crystal (1) by using the derivative of ethylenediammonium cations (N,N,N′,N′-tetra-p-methoxybenzyl-ethylenediamine, L1) and [CuCl4]2−anions. The reaction was carried out by mixing MeOH solution of CuCl2·2H2O and HCl/MeOH solution of L1at room temperature. Two types of inclusion compounds can be formed when using different guest molecules. When guest molecules, such as anthracene or phenanthrene, were included, it resulted in the formation of interlayered structures: anthracene ⊂ [H2L1]2+·[CuCl4]2−(2) and phenanthrene ⊂ [H2L1]2+·[CuCl4]2−(3). When β-naphthyl phenol were included, it led to the formation of pillared-layered complexes of [1-chloride-β-naphthyl phenol]1.0·[β-naphthyl phenol]0.5·[methanol]1.0⊂ 2[H2L1]2+·2Cl−·[CuCl4]2−(4). [ABSTRACT FROM AUTHOR]