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In this study, we report a facile polymeric citrate strategy for the synthesis of Cr,La-codoped SrTiO3 nanoparticles. The synthesized samples were well characterized by various analytical techniques. The UV-vis DRS studies reveal that the absorption edge shifts towards the visible light region after doping with Cr, which is highly beneficial for absorbing the visible light in the solar spectrum. More attractively, codoping with La exhibits greatly enhanced photocatalytic activity for the degradation of Rhodamine B under sunlight irradiation. The optimum photocatalytic activity at 1 atom% of Cr,La-codoped SrTiO3 nanoparticles is almost 6 times higher than that of pure SrTiO3 nanoparticles and 3 times higher than that of Cr-doped SrTiO3 nanoparticles. The high photocatalytic performance in the present photocatalytic system is due to codoping with La, which acts as a most effective donor for stabilizing Cr(3+) in Cr,La-codoped SrTiO3 nanoparticles. More importantly, the synthesized photocatalysts possess high reusability. A proposed mechanism for the enhanced photocatalytic activity of Cr,La-codoped SrTiO3 nanoparticles was also investigated by trapping experiments. Therefore, our results not only demonstrate the highly efficient visible light photocatalytic activity of the Cr,La-codoped SrTiO3 photocatalyst, but also enlighten the codoping strategy in the design and development of advanced photocatalytic materials for energy and environmental applications.

Mesoporous metals are useful for heterogeneous catalysis because their ultrapermeable architecture promotes mass transport to abundant active sites. Our group recently developed a method to manipulate the interior space of nanocrystals by synthesizing mesoporous Rh nanospheres that serve as high performance catalysts for methanol oxidation and nitric oxide (NO) remediation (Jiang, B.; et al. Nat. Commun. 2017, 8, 15581). Here, we extend this concept and propose a sophisticated soft-templating strategy to synthesize three-dimensional mesoporous bimetallic RhCu nanospheres. The nanospheres are alloys of Rh and Cu, and their compositions can be continuously tuned by varying the amount of metal precursors. The mesoporous RhCu nanospheres were examined for catalytic remediation of NO and show good catalytic performance considering the reduced economic cost of the alloyed material. This method offers a general approach for the precise design of high surface area Rh-based metal catalysts.

Diminishing fossil fuels and global warming issues have forced the scientists to look for alternate sources of energy to cater to the ever increasing demand. Artificial systems are being developed in order to mimic natural photosynthesis and directly harvest and convert solar energy into renewable energy and environmental remediation. Despite significant efforts, it has been not possible to design a single material which has sufficient efficiency, stability and low cost. To integrate the desired characteristics in a single component, heterogeneous photocatalysts are designed with multiple functional components which could combine the advantages of different components to overcome the drawbacks of single component photocatalysts. The present highlight gives a concise overview of heterogeneous catalysts that have been developed and studied in our group and some excellent works of others in recent years. The review focuses on the principles of photocatalytic and electrocatalytic activity followed by the some key examples of oxide based materials. This includes a wide range of structural modification and crystal growth leading to composites, heterostructures, including insulator/semiconductor, semiconductor/semiconductor, and multi-hetero nanostructures and core-shell nanostructures which have been modified in order to improve the performance by increasing the light absorption, promoting the charge separation and transportation, enhancing the redox catalytic activity and intrinsic electrocatalytic properties. The electrochemical processes like hydrogen

Three crystalline compounds, [Bi(2-O(2)C-C(5)H(4)N)(3)](n) (), {Bi[(2,6-O(2)C)(2)C(5)H(3)N)][(2-HO(2)C-6-O(2)C)C(5)H(3)N].H(2)O}(n) (3) and Bi(O(2)CC(9)H(6)N)(2)(O(3)N)(O(2)CC(9)H(6)NH).2H(2)O () have been prepared by simple reactions in aqueous medium using the readily available bismuth nitrate and the corresponding acids, picolinic acid, dipicolinic acid and quinaldic acid. While and are coordination polymers with bismuth in tricapped trigonal prismatic and dodecahedral environments, compound is a monomeric species with dodecahedral geometry at bismuth. Compound represents a second crystalline form of a recently reported structure with subtle differences in bond parameters, and highlights the flexibility in structural motifs during crystallization. Compound involves skeletons with dimeric [Bi(2)O(2)] and trimeric [BiOCOBiOBiOCO] moieties. In , while the N-protonated carboxylate forms a four-membered chelate ring with bismuth, the other two carboxylates form five-membered ring chelates with the nitrate accounting for the remaining two sites again as a chelate. TGA studies are consistent with the presence of non-coordinated water in and . Compounds and , although insoluble in most of the organic solvents and water, are readily soluble in dilute hydrochloric acid.