We develop a facile method to prepare cobalt phosphate nanoparticles coated by N-doped carbon layers for highly active and stable OER electrocatalyst.

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Hydrogenation and cross-coupling reactions are of great importance for industrial applications and noble metal based catalysts are filling the void since the last few decades. However, the high cost of noble metals and poor recycling performance provides an opportunity for chemists to look for alternate options. Herein, we present the use of Lanthanum hydroxide as support for loading ultra-low amount of Pd for hydrogenation and cross-coupling reactions. Lanthanum hydroxide having controlled morphologies comprises exposed crystallographic facets which interact with small sized Pd NPs and shows versatile and effective catalytic performance. The reduction of 4-NP over Pd/La(OH)3 was achieved within very short time (45s) with a rate constant of 60 × 10−3 s−1. The hydrogenation of styrene was also accomplished within 1 hour with much high TOF value (3260 h−1). Moreover, the Suzuki cross-couplings of iodobenzene and phenyl boronic acid into biphenyl completed within 35 min with a TOF value of 389 h−1. The strong interfacial electronic communication regulates electron density of catalytic sites and lowers energy for adsorption of reactant and subsequently conversion into products. Moreover, abundant hydroxyl groups on the surface of La(OH)3, large surface area, mono-dispersity and ultra-small size of Pd NPs also favors the efficient conversion of reactants.

A procedure for the preparation of copolymers bearing sulfobetaine and carboxybetaine methacrylic-based monomers by free-radical polymerization is described and discussed. A combination of monomers affects the upper critical solution temperature (UCST) in water and in the presence of a simple NaCl electrolyte while retaining the zwitterionic character. In addition, hydrogel samples were prepared and showed tunable water structure and mechanical properties. The total nonfreezable water content decreases with the amount of carboxybetaine segment in the hydrogel feed and the compression moduli were in a range of 0.7-1.6 MPa. Responses to external conditions such as temperature and ion strength were investigated and a potential application such as modulated thermal detection is proposed. The presence of the carboxylate group in the carboxybetaine segment enables a small fluorescence probe and peptide bearing RDG motif to be attached to polymer and hydrogel samples, respectively. The hydrogel samples functionalized with the RGD motif exhibit controlled cell adhesion. Such synthetic strategy based on combination of different zwitterionic segments offers a simple pathway for the development of zwitterionic materials with programmable properties.

Artificial enzyme mimetics is a current research area with much interest from scientific community. Some nanomaterials have been found to possess intrinsic enzyme-mimetic activity. In this study, VO nanoflakes with mixed-phases are synthesized via a quick and facile one-pot synthetic process and their Fenton reaction and enzyme-mimetic activities have been studied. The results show that obtained VOx is not only highly effective Fenton reagent, completely decomposing Rhodamine B (RhB) within less than 1 min, but also exhibits excellent intrinsic peroxidase-like activity as well as HO catalase-like activity. Our results suggest that this VO nanomaterial can effectively mimic the enzyme cascade reaction of horseradish peroxidase (HRP). VO nanoflakes have excellent affinity toward 3,3',5,5'-tetramethylbenzidine (TMB) for oxidation and henceforth, it can be used for the colorimetric assay of glucose and HO. Moreover, this study indicates that VO nanoflakes can also be used for the efficient degradation of environmental pollutants.

Oxygen-sensitive photoreversible intelligent ink capable of assessment with the human eye is an ongoing demand in the modern era. In the food industry, redox-dye-based oxygen indicator films have been proposed, but the leaching of dyes from the film that contaminates the food is one unsolved issue. On the other hand, it is also highly desirable to develop rewritable paper that significantly reduces the pressure on modern society for the production and consumption of paper. Herein, we have developed an oxygen-deficient TiO2 - x/methylene blue (MB) sol without relying on external sacrificial electron donors (SEDs) for photoreversible color switching. Oxygen vacancies in TiO2 - x can work as electron donor to favor the adsorption of the substrate and improve the charge separation that is required for the redox-based color-switching system. The problems of rewriteable paper and food packaging are addressed as two sides of a single coin in this article. We have used hydroxyethyl cellulose (HEC) for rewritable paper that can significantly delay the oxidation of leuco-MB (LMB) through hydrogen bonding and retain the printed information for a long time. The dye leaching from oxygen indicator films is also significantly reduced (only 1.54%) by using furcelleran as the coating polymer that is extracted from edible red seaweed.

Direct methanol fuel cell (DMFC) with noble metals based anode and cathode is a promising energy generator to portable power devices. However, the deterioration of catalyst performance suffered by CO poisoning, crossover of fuel from anode to cathode, and higher economical cost of such devices hinder their commercialization. Herein, all of the above issues have been neutralized and crossed the huge hump of faced challenges. Highly efficient, durable, and surfactant-free catalyst with ultralow Pt3Pd1 loadings supported on CeO2/C was synthesized. The ex-situ and in situ spectroelectrochemical techniques such as, CV, in situ FTIR, and online DEMS studies confirm the highly efficient activity of catalyst toward electro-oxidation of methanol. In addition, the critical and detailed analysis of RDE results prove the superiority of the present material for electro-reduction of oxygen along a cathode side. The as-synthesized catalyst has proven itself as a better substitute for commercial Pt/C catalyst, with enhanced and durable performance as anode and cathode material for DMFCs. The obtained remarkable performance of catalysts can be attributed to the accumulative effects of PtPd bimetallic NPs and the enhanced synergistic factors of CeO2 in a hybrid material.

P doped MoO2 nanoparticle films on Mo foil used as electrodes for an efficient and stable electrocatalytic hydrogen evolution reaction (HER).