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The continuous and sustainable photo-activity on micro- or nano-carriers has always been a key stepping stone in the industrialization of photo-catalysis, photo-synthesis, and photo-degradation. Herein, we report a new series of positively charged hollow microspheres carrying porphyrin moieties. Such hollow spheres are formed through crosslinking of well-ordered porous thin laminates, initiated by co-assembly of regular monomers and those decorated with porphyrin moieties. On the surface of an individual sphere, densely distributed positive sites attract anionic reactants. The superficial porphyrin decomposes the accumulated reactants under 1 Sun. After degradation and release of products, the photoactive sites are thereby renewed. We demonstrate that polymer network (1:10) exhibited superior sustainable photocatalytic performance with complete degradation of methyl orange (MO) in 40 min with no observable performance deterioration after six cycles. The established close loop of adsorption–reaction–release cycle makes possible many efficient and continuous photo-catalytic processes. [ABSTRACT FROM AUTHOR]

Reaction of M(OAc)2·xH2O (M, x = Zn, 2 and Co, 4), 1,4-dihydro-5,6-dicyano-2,3-pyrazinedione (H2CN2pyzdione), and pyrazine (pyz) affords two compounds of the same molecular formula {[M(H2O)6][M(CN2pyzdione)2(pyz)]·6H2O}n (M = Zn for 1 and Co for 2) in which discrete units of [M(H2O)6]2+ are linked to one-dimensional chains of [M(CN2pyzdione)2(pyz)]2– via multiple O–H···O hydrogen-bonding interactions and M2+-bound H2O molecules in [M(H2O)6]2+ also serve as linkers of hydrogen-bonded interstitial H2O molecules. Remarkably, 1 crystallizes in the monoclinic crystal system, the similar crystal system and unit cell parameters as 2, but with a space group distinct from 1 and 2, i.e., 1 is the noncentrosymmetric space group C2, whereas 2 is the centrosymmetric space group C2/m. This polar structure for 1 is induced by the presence of alternating arrangements of distinguishable two axial Zn–N bonds within [Zn(CN2pyzdione)2(pyz)]2– chains. Indeed, solid-state circular dichroism spectra of 1 exhibit significant Cotton effects, as evidenced by the polar space group C2. Moreover, these Cotton effects show clear temperature-dependence depending on contents of H2O molecules of 1.

Reaction of M(OAc)2·xH2O (M, x = Zn, 2 and Co, 4), 1,4-dihydro-5,6-dicyano-2,3-pyrazinedione (H2CN2pyzdione), and pyrazine (pyz) affords two compounds of the same molecular formula {[M(H2O)6][M(CN2pyzdione)2(pyz)]·6H2O}n (M = Zn for 1 and Co for 2) in which discrete units of [M(H2O)6]2+ are linked to one-dimensional chains of [M(CN2pyzdione)2(pyz)]2– via multiple O–H···O hydrogen-bonding interactions and M2+-bound H2O molecules in [M(H2O)6]2+ also serve as linkers of hydrogen-bonded interstitial H2O molecules. Remarkably, 1 crystallizes in the monoclinic crystal system, the similar crystal system and unit cell parameters as 2, but with a space group distinct from 1 and 2, i.e., 1 is the noncentrosymmetric space group C2, whereas 2 is the centrosymmetric space group C2/m. This polar structure for 1 is induced by the presence of alternating arrangements of distinguishable two axial Zn–N bonds within [Zn(CN2pyzdione)2(pyz)]2– chains. Indeed, solid-state circular dichroism spectra of 1 exhibit significant Cotton effects, as evidenced by the polar space group C2. Moreover, these Cotton effects show clear temperature-dependence depending on contents of H2O molecules of 1. [ABSTRACT FROM AUTHOR]

Silica‐graphene hybrid (HGKS) with good dispersion and strong interfacial interactions was fabricated by hydrogenbonding assembly. HGKS was incorporated into natural rubber (NR) to develop high‐performance tire treads. During vulcanized process of HGKS filled NR (NR/HGKS), HGKS can participate in the process to form dual dynamic network structure. The interfacial interaction between HGKS and NR due to the dispersion of HGKS was investigated. The strong covalent interaction between NR and HGKS is the most important factor to determine the ultimate performance of rubber composites. In this contribution, a series of HGKS with different hybrid grafting ratio are prepared to reveal the effects of changes in filler surface properties on the structure and mechanical properties of rubber composites. It has been demonstrated that it is an effective hybrid technique to drastically improve its dispersibility in NR and form strong interfacial reactions, and HGKS is expected to be used as a new type of reinforcing filler for the manufacture of high‐performance green tire materials. [ABSTRACT FROM AUTHOR]

A new metal-organic NLO single crystal of 2-Aminopyridinium bis[hexaaqua(cobalt(II)) sulfate] monohydrate (2APCS) has been obtained by the reaction of aqueous solution of 2-Aminopyridine and cobalt(II) sulfate heptahydrate and by room temperature slow evaporation process. Single crystal X-ray diffraction study of the grown single crystal confirms the P 1 ¯ space group of a triclinic structure. The crystalline molecules are stabilized by elaborate O H⋯O and N H⋯O classical three dimensional hydrogen bonding network. The functional groups in the 2APCS were established by the FT-IR and Laser Raman spectroscopy. The obtained crystals were also characterized for thermal stability, dielectric, optical and nonlinear optical properties. Z-Scan technique was employed to observe the third order nonlinear optical susceptibility and was observed to be high. The optical limiting behaviour of the grown crystal is recognized mainly to nonlinear refraction. A new organometallic NLO single crystals of 2-Aminopyridinium bis[hexaaqua (cobalt(II)) sulfate] monohydrate was synthesized by slow evaporation method and the molecular structure was confirmed by single crystal X-ray diffraction study. From Z-scan study, nonlinear refractive index, nonlinear absorption and third order nonlinear susceptibility values were calculated. The optical limiting behaviour observed with the crystal is attributed mainly to nonlinear refraction. Image 1070 • A new metal-organic single crystals of 2-Aminopyridinium bis [hexaaqua(cobalt(II)) sulfate] monohydrate has been grown by slow evaporation solution growth technique. • The structure is reported for the first time in the literature. • The optical quality and thermal stability of the 2APCS crystal was studied by UV–Vis–NIR and TG/DTA. • The electrical conductivity, dielectric loss and dielectric constant have been investigated. • The grown crystal exhibited high third order optical nonlinearity which was determined by Z-Scan technique. [ABSTRACT FROM AUTHOR]