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Dye-sensitized solar cells (DSSCs) have turned to be the most promising PV technology for indoor applications, for sustainable powering billions of IoT devices and wireless indoor sensors; DSSCs are aesthetic, cheap, and safe, and they display extremely high power conversion efficiencies (PCEs). In this study, poly­(4-vinylpyridine) (P4VP) of molecular weights (MW) ranging from 2.8 to 18.5k was prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization and studied as a new co-adsorbent with N719 dye to produce efficient DSSCs. P4VP adsorbs on TiO2 via coordinative bonding to the Lewis acid centers of the titania. The adsorbed P4VP effectively hampers the back-electron recombination at the photoanode/electrolyte interface and promotes stronger covalent dye bonding. The simultaneous adsorption of P4VP with N719 allowed reaching a PCE of ca. 7.5% under 1 Sun and with almost half dye loading of the reference device. Sequential adsorption of the P4VP led to a noticeable increase of the strongly covalent bonded dye fraction making the electron injection to the titania more efficient and improving the photocurrent density. The effect of polymer MW, concentration, and adsorption sequence with the N719 on the photovoltaic performance of the DSSCs is discussed. For the first time ever, the efficient long-chain polymeric P4VP co-adsorbent rendered a device with as high PCE as 9% under 1 Sun illumination and 22.5% under indoor 1000 lx light. The PCE history under natural aging suggests that P4VP is a high-performing co-adsorbent, which allows fabrication of quite stable devices.

The herbicide terbuthylazine (TBA) is widely used for preemergence or postemergence control of many grass and broadleaf weeds and has, besides other issues, a poor aqueous solubility profile that results in reduced bioavailability. Cyclodextrins and modified cyclodextrins were considered, among other substances, appropriate agents for improving pesticide water solubility. Therefore, the inclusion complex formation of terbuthylazine with -cyclodextrin ( -CD) and hydroxypropyl--cyclodextrin (HP--CD) was studied to attain its aqueous solubility enhancement. Their characterization was accomplished with different analytical techniques, namely, by UV-Vis, DSC, FTIR, and 1 H NMR. From the analysis of the complexation performance of the herbicide it was concluded that the interaction of terbuthylazine with CDs leads to the formation of inclusion complexes with a stoichiometry of 1 : 1. The association constants of the TBA/ -CD and TBA/HP--CD complexes were determined by UV. The mean values obtained for the stability constants are 460.4 ± 26.5 and 532.1 ± 27.6 to TBA/ -CD and TBA/HP--CD, respectively.1 H NMR data corroborate the formation of the TBA/ -CD and TBA/HP--CD complexes synthesized by the kneading method. A formulation incorporating TBA cyclodextrin complexes might lead to an improvement in terbuthylazine bioavailability. The development of TBA-CD formulations may be interesting since it would enable, through their inclusion into the hydrophobic cavity of CDs, enhancement of solubility, bioavailability, and stability of the herbicide.

The side chain effect on transport in ionic aqueous salt solutions was investigated for [Formula: see text]-amino acids glycine, alanine, [Formula: see text]-amino butyric acid, norvaline, and norleucine --that together define a chemical homologous series based on the length of the characteristic side chain which increases from zero to four carbons, respectively. Binary mutual diffusion coefficients at infinitesimal concentration in aqueous solutions of NaCl (0.15 mol kg ) are measured by means of Taylor dispersion technique for this series and significant differences were found against previous published results for identical systems in pure water. In this way, NaCl effect on the transport of each amino acid is thus assessed and discussed in terms of salting-out effects. Also, solvated Stokes hydrodynamic radii were computed for the series showing comparable results in water and NaCl solution. The new information should prove useful in the design and characterization of transport-controlled systems in physiological and pharmacological studies.

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