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A novel class of copolyesters containing the metallophthalocyanine ring [M-Pc, M=Fe(III), Co(II)] in the chain was synthesized by polycondensation of (dicarboxyphthalocyaninato) metal [M-Dapc, M=Fe(III), Co(II)] diacid chloride, terephthalic acid chloride and aliphatic diols. The structures of the copolyesters were characterized by infrared, electronic as well as ESR spectra, and viscosity measurement. The thermal stabilities of the polymers were evaluated by dynamic thermogravimetric analyses. The polymers obtained thus were easily soluble in chloroform, dichloromethane, etc. The green or blue colored fiber was formed by melt spinning of the copolyesters containing below 1 mol % M-Pc component. The copolyester containing Co(II)-Pc in the chain obtained from 1,2-ethanediol as a diol component catalysed the autoxidation of 2-mercaptoethanol in the presence of oxygen.

Atomic adsorptions of N, C and O on silicene and molecular adsorptions of N₂ and CO on silicene have been investigated using the density functional theory (DFT) calculations. For the atomic adsorptions, we find that the N atom has the most stable adsorption with a higher adsorption energy of 8.207 eV. For the molecular adsorptions, we find that the N₂ molecule undergoes physisorption while the CO molecule undergoes chemisorption, the corresponding adsorption energies for N₂ and CO are 0.085 and 0.255 eV, respectively. Therefore, silicene exhibits more reactivity towards the CO adsorption than the N₂ adsorption. The differences of charge density and the integrated charge calculations suggest that the charge transfer for CO adsorption ($\sim$0.015$e$) is larger than that for N₂ adsorption ($\sim$0.005$e$). This again supports that CO molecule is more active than N₂ molecule when they are adsorbed onto silicene.

This report presents the easily reproducible biosynthesis of gold nanoparticles (AuNPs) at room temperature with extract prepared using three year old dried Garcinia Indica (GI) fruit rind. Due to the presence of two major bioactive compounds garcinol and hydroxy citric acid, rinds of GI fruit exhibit anti-cancer and anti-obesity properties. The quantity of fruit rind extract directed the morphology of the as synthesized particles. The nucleation and growth of AuNPs and catalytic activity are studied using UV-Vis spectroscopy. The crystalline nature of biosynthesized AuNPs is corroborated by X-ray Diffraction techniques. The morphology is studied using field emission scanning electron microscopy (FESEM). Fourier transform infra-red (FTIR) spectroscopy analysis revealed that biomolecules were involved in the synthesis and capping of AuNPs. As the Fermi potential of noble metal NPs becomes more negative, they are used in various electron transfer processes. The AuNPs produced using GI extract showed excellent catalytic activity when used as a catalyst in the reduction of well-known toxic pollutant 4-Nitrophenol (4-NP) to 4-Aminophenol (4-AP) in the presence of excess sodium borohydride.

Five iron tetraphenylporphyrins including the (TPP)FeCl and its derivatives which contain electron-withdrawing or electron-donating substituents on the meso-phenyl rings of the porphyrin macrocycle were examined as catalysts for the electoreduction of dioxygen in 1.0 M HClO₄. The investigated compounds are represented as (TpRPP)FeCl, where TpRPP is the dianion of the para-substituted tetraphenylporphyrin and R = NEt₂, OMe, H, Br or CF₃. Cyclic voltammetry and linear sweep voltammetry at a rotating disk electrode (RDE) or a rotating ring disk electrode (RRDE) were utilized to examine the catalytic activity of the compounds. The number of electrons transferred and the percentage of H₂O₂ produced as the product of O₂ electroreduction were calculated. The investigated iron porphyrins containing electron-withdrawing substituents (R = Br and CF₃) were shown to be more efficient catalysts for O₂ reduction than the compounds having electron-donating groups (R = NEt₂ and OMe) on the four phenyl rings of the porphyrin macrocycle.

Two metal-free porphyrins H${}_2$Pp (a, b) and four metalloporphyrins CuPp (a, b) and ZnPp (a, b) have been applied to lithium/thionyl chloride (Li/SOCl${}_2)$ battery as the high efficient catalysts for the first time. Notably, the battery discharge time in blank is only 1080 s while that of Li/SOCl₂ battery after adding porphyrin/metalloporphyrins is 1980 s for H${}_2$Pp (a), 2160 s for H${}_2$Pp (b), 1560 s for CuPp (a), 1320 s for CuPp (b), 1620 s for ZnPp (a), and 1680 s for ZnPp (b), respectively. Furthermore, the energy of the battery whose electrolyte contains the H${}_2$Pp (a, b), CuPp (a, b) and ZnPp (a, b) increases by approximately 11.88–77.14% than that of the battery without them. And the metal-free porphyrins H${}_2$Pp (a) or H${}_2$Pp (b) exhibit higher catalytic activities than that of metalloporphyrins CuPp (a, b) and ZnPp (a, b). In addition, the possible reasons to explain the excellent results were also analyzed.

Three-dimensionally ordered macroporous (3DOM) CuO is prepared by colloidal crystal templated method. The obtained 3DOM structure with about 230nm pore diameter is composed of small CuO windows. The special structured CuO is used as a catalyst for thermal decomposition of ammonium perchlorate (AP) and its catalytic activity is measured by simultaneous thermogravimetry-differential scanning calorimetry (TG-DSC) techniques. Test results show that thermal decomposition performance is significantly improved after adding 2wt.% 3DOM CuO.

Zn-doped Fe₃O₄ has been employed as a catalyst for the photo-Fenton process. At the present study, the influence of Zn content in the Zn-doped Fe₃O₄ on the catalytic activity for the photo-Fenton process was studied. Monodispersed Zn_xFe${}_{3-x}$O₄ particles were facilely synthesized with higher surface area and several nm of diameter, where $x=0$, 0.4 and 1.0. Rhodamine B (Rh B), as one of the positive dyes, was selected as a model pollutant. The decolorization efficiency of the Fe₃O₄ ($x=0$) for Rh B reached about 90% in 120min under visible light. The Zn content increase in the Zn-doped Fe₃O₄ inhibited the Fenton process. The higher molar ratio of Fe${}^{2+}$ to Fe${}^{3+}$, smaller band-gap, and more negative zeta potential of the Fe₃O₄ induced the most excellent photo-Fenton performance for the Rh B degradation.

In this paper, a facile, surfactant-free and mild solution chemistry route was employed to prepare copper sulfide (CuS–Cu₉S₈) nanoparticles (NPs) by using anion-controlled agents with a different electronegativity. Counterions CH₃COO⁻ were found to be suitable for regular hexagonal morphology formation, whereas in the presence of ${\text{NO}}_3^{-}$, irregular structure is obtained. By changing the anion of the copper precursor, the ratio of formation of Cu₉S₈ and CuS can be changed, and the band gap energy (Eg) of as-prepared NPs can be controlled in the presence of anion-controlled agents. Moreover, we demonstrate here the catalytic performance of the as-prepared samples for the degradation of methylene blue (MB) both under the simulated natural light and in dark, and the result shows that the CuS–Cu₉S₈ NPs exhibited better catalytic activity under visible light ($>50$%) than in darkness (45%), and CuS–Cu₉S₈ NPs with higher electronegativity of anion-controlled exhibited the higher catalytic performance. In addition, a simple and direct diagram was applied to illustrate the mechanism of the degradation of MB.

VO₂(M) nanobelts were successfully synthesized using commercial V₂O₅, ethanol and water as the starting materials by a template-free hydrothermal method and subsequent calcination. The as-obtained products were characterized by X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). Furthermore, the study on the influence of the as-prepared VO₂(M) nanobelts on the thermal decomposition of ammonium perchlorate (AP) were evaluated by Thermo-Gravimetric Analysis and Differential Thermal Analysis (TGA/DTA), which showed the thermal decomposition temperatures of AP in the presence of the as-prepared VO₂(M) nanobelts were reduced to 421 °C (decreased by 35 °C). The results indicated that VO₂(M) nanobelts had great influence on the thermal decomposition temperature of AP.