Intercalation of perylenediimide dye into a host layer of layered double hydroxide (LDH) by the anionexchange method is studied. N,N 0 -Bis(4-benzosulfonic acid)perylene-3,4,9,10-tetracarboxylbisimide disodium salt (PRSA) has been synthesized and intercalated into the perchlorate form of ZnAl-, CoAl-, and NiAl-LDH. LDH composite with welldefined morphology has been prepared. XRPD and FT-IR investigation show successful intercalation of PRSA, and the interlayer distances are 32.5 Å for ZnAl-LDH-PRSA, 30.0 Å for CoAl-LDH-PRSA, and 31.2 Å for NiAl-LDH-PRSA. These values support the presence of monolayer arrangement of intercalated PRSA molecules in the composite and also indicate vertical orientation of PRSA molecules with the basal plane of LDH. Photophysical properties of these intercalated composites have been measured with UV-vis spectroscopy, photoluminescence spectroscopy, and confocal laser scanning microscopy. The results indicate that the PRSA molecules are stacked in J-type aggregation in the interlayer region. Intercalated PRSA molecules show enhanced thermal and photophysical stabilities.

The electrochemical reduction of CO2 (CO2RR) to produce valuable synthetic fuel like CH3OH not only mitigates the accumulated greenhouse gas from the environment but is also a promising direction toward attenuating our continuous reliance on fossil fuels. However, CO2RR to yield CH3OH suffers because of large overpotential, competitive H2 evolution reaction (HER), and poor product selectivity. In this regard, intermetallic alloy catalysts open up a wide possibility of fine-tuning the electronic property and attain appropriate structures that facilitate selective CO2RR. Here, we report for the first time the CO2RR over carbon-supported PtZn nano-alloys and probed the crucial role of structures and interfaces as active sites. PtZn/C, Pt3Zn/C, and Pt x Zn/C (1 < x < 3) synthesized from the metal–organic framework material were characterized structurally and morphologically. The catalysts demonstrated structure dependency toward CH3OH selectivity, as the mixed-phase Pt x Zn/C outperformed the phase-pure PtZn/C and Pt3Zn/C. The structure-dependent reaction mechanism and the kinetics were elucidated over the synthesized catalysts with the help of detail experiments and associated density functional theory calculations. Results showed that in spite of low electrochemically active surface area, Pt x Zn could not only have facilitated the single electron transfer to adsorbed CO2 but also showed better binding of the intermediate CO2 •– over its surface. Moreover, the lower bond energy between the mixed-phase surface and −OCH3 compared to the phase-pure catalysts has enabled higher CH3OH selectivity over Pt x Zn. This work opens a wide possibility of studying the role of interfaces between phase-pure nano-alloys toward CO2RR.

Herein, we fabricated the ordered polymer nanostructures by compositing the electrochromic polymer polyFe to significantly improve the colouration efficiency and switching times.

Environmental context. The environmental fate and bioavailability of metal ions in natural waters is determined by their thermodynamic stability and kinetic features, both of which are distributed and depend on the metal ion loading of the system. Diffusive gradients in thin film (DGT) is a dynamic technique for metal speciation analysis that measures a certain portion of these complexes as determined by its operational timescale. Reliable interpretation of data furnished by DGT necessitates characterisation of its features for the particular case of heterogeneous complexes. Abstract. Owing to their inherent heterogeneity, the thermodynamic stability of metal ion complexes with natural ligands is characterised by a distribution, and thus is a function of metal-to-ligand ratio. The kinetic features of such metal complexes are also distributed and can be probed by dynamic speciation techniques. The kinetic regime of the metal complex sample can be manipulated via the metal-to-ligand ratio, and the timescale over which kinetic parameters are actually in effect is defined by the window of the chosen technique. Here we detail the kinetic features of diffusive gradients in thin film (DGT), and show that the range of attainable measurement timescales (τ) is rather limited: variation of the gel layer thickness practically allows only one order of magnitude in τ to be scanned. The more effective use of DGT to probe the distribution of dynamic metal species in heterogeneous systems is via variation of the metal-to-ligand ratio in the sample solution. Compilation of the literature DGT data for natural waters shows that by assuming a Freundlich isotherm relationship, the degree of heterogeneity is reflected in the measured DGT concentration as a function of metal ion loading.

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