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A microbubble nucleated due to the absorption of a tightly focused laser at the interface of a liquid-solid substrate enables directed and irreversible self-assembly of mesoscopic particles dispersed in the liquid at the bubble base. This phenomenon has facilitated a new microlithography technique which has grown rapidly over the past decade and can now reliably pattern a vast range of soft materials and colloids, ranging from polymers to metals to proteins. In this review, we discuss the science behind this technology and the present state-of-the-art. Thus, we describe the physics of the self-assembly driven by the bubble, the techniques for generating complex mesoarchitectures, both discrete and continuous, and their properties, and the various applications demonstrated in plastic electronics, site-specific catalysis, and biosensing. Finally, we describe a roadmap for the technique to achieve its potential of successfully patterning "everything" mesoscopic and the challenges that lie therein.
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The eleven monohydrates of 1, 2, 3, 4-tetrahydroisoquinoline (THIQ) are analyzed through natural bond orbital (NBO) analysis and QTAIM methods employing M06-2X functional in DFT and MP2 methods. Here, the role of OH bonds as an acceptor and donor is critically analyzed. The role of lone pairs of O is critically monitored in two of the complexes, where N-H···O hydrogen bonds are present. The relative contributions of rehybridisation and hyperconjugation are compared in detail. Popelier criteria are satisfied in all the complexes barring a few exceptions involving weak hydrogen bonds. At the bond critical points (BCP), four monohydrates show higher values of electron density (ρC) and negative values of total electron energy density (HC), while Laplacian [Formula: see text] remains positive. These complexes satisfy the criteria of partial covalency. All these are O-Hâ â â N-type bonds. Remaining h-bonds are weaker in nature. These are also confirmed by the smaller values of ρC at the respective BCP. The variation of potential energy density (VC) among the complexes seems to be the most important factor in determining the nature of non-covalent interactions.
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Tetra-Hidroisoquinolinas , Ligação de HidrogênioRESUMO
Correction for 'Selective light driven reduction of CO2 to HCOOH in water using a {MoV9}n (n = 1332-3600) based soft-oxometalate (SOM)' by Soumitra Barman et al., Chem. Commun., 2018, 54, 2369-2372, DOI: 10.1039/C7CC09520A.
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[This corrects the article DOI: 10.3389/fchem.2018.00514.].
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Photocatalytic CO2 reduction in water is one of the most attractive research pursuits of our time. In this article we report a giant polyoxometalate {Mo368} based homogeneous catalytic system, which efficiently reduces CO2 to formic acid with a maximum turnover number (TON) of 27,666, turnover frequency (TOF) of 4,611 h-1 and external quantum efficiency of the reaction is 0.6%. The catalytic system oxidizes water and releases electrons, and these electrons are further utilized for the reduction of CO2 to formic acid. A maximum of 8.3 mmol of formic acid was observed with the loading of 0.3 µmol of the catalyst. Our catalyst material is also stable throughout the reaction. The starting materials for this experiment are CO2 and H2O and the end products are HCOOH and O2. The formic acid formed in this reaction is an important H2 gas carrier and thus significant in renewable energy research.
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A soft-oxometalate (SOM) based on Mo and V i.e. {MoV9} in their highest oxidation state reduces CO2 to HCOOH selectively in water. Catalysis initiates without the use of any photosensitizer and solvent water acts as the sacrificial electron donor which gets oxidized to generate oxygen. Electrons and protons released in this process reduce CO2 to HCOOH.
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An immediate challenge for chemists is to devise different methods to trap chemical energy using light by reduction of carbon dioxide to a transportable fuel. To reach this goal the major obstacle lies in finding a suitable material that is abundant and possesses catalytic power to effect such reduction reaction and perform this reduction reaction without using any external photosensitizer. Here we report for the first time a softoxometalate based on a {[K6.5Cu(OH)8.5(H2O)7.5]0.5[K3PW12O40]} metal oxide framework which is stable in reaction conditions that effectively performs photochemical CO2 reduction reaction in water with a very high turnover number of 613 and TOF of 47.15 h-1. We observe that during this reaction water gets oxidized to oxygen, while the electrons released directly go to CO2 reducing it to formic acid. A detailed account of the characterization of the catalyst along with that of products of this reaction is reported.