Theoretical investigation of the carbonyl-ene reaction between encapsulated formaldehyde and propylene over M-Cu-BTC paddlewheels (M= Be, Mg, and Ca): A DFT study.

Formaldehyde is a VOC gas that plays a key role in air pollution. To limit emissions into the environment, the utilization of this waste as a raw material is a promising way. In this work, the M06-L functional calculation was used to investigate the structure, electronic properties, and catalytic activity of group IIA metals (Be, Mg, and Ca) partial substitution on Cu-BTC paddlewheels for formaldehyde encapsulation and carbonyl-ene reaction with propylene.

Understanding the effect of the divalent cations (Ni, Cu, and Zn) exchanged FAU zeolite on the kinetic of CO cycloaddition with ethylene oxide: A DFT study.

Epoxide ring opening and cycloaddition with CO is one of the promising routes to convert CO to more valuable industrial chemicals. In this work, density functional theory calculations with the M06-L/6-31G(d,p) level of theory have been employed to study the cycloaddition of ethylene oxide (EO) with CO over M(II)-faujasite zeolite (M = Ni, Cu, and Zn) in the absence of a co-catalyst. The influence of the exchanged metals strongly dominates the adsorption of EO.

Moisture-Resistant Electrospun Polymer Membranes for Efficient and Stable Fully Printable Perovskite Solar Cells Prepared in Humid Air.

Fully printable perovskite solar cells (PPSCs) attract attention in the photovoltaic industry and research owing to their controllable and scalable production with reduced material waste during manufacturing. However, the commercialization of PPSCs has been impeded by their inherent vulnerability to ambient moisture, leading to a rapid loss of device efficiency and lifetime. Here, we propose a novel idea to enhance the photovoltaic performance and stability of PPSCs in humid air (relative humidity exceeding 80%) using electrospun hydrophobic polymer membranes, i.

Charge storage mechanisms of manganese oxide nanosheets and N-doped reduced graphene oxide aerogel for high-performance asymmetric supercapacitors.

Although manganese oxide- and graphene-based supercapacitors have been widely studied, their charge storage mechanisms are not yet fully investigated. In this work, we have studied the charge storage mechanisms of K-birnassite MnO nanosheets and N-doped reduced graphene oxide aerogel (N-rGO) using an in situ X-ray absorption spectroscopy (XAS) and an electrochemical quart crystal microbalance (EQCM). The oxidation number of Mn at the MnO electrode is +3.

Conversion of CO2 and C2H6 to propanoic acid over a Au-exchanged MCM-22 zeolite.

Finding novel catalysts for the direct conversion of CO2 to fuels and chemicals is a primary goal in energy and environmental research. In this work, density functional theory (DFT) is used to study possible reaction mechanisms for the conversion of CO2 and C2H6 to propanoic acid over a gold-exchanged MCM-22 zeolite catalyst. The reaction begins with the activation of ethane to produce a gold ethyl hydride intermediate.

Persistence of magic cluster stability in ultra-thin semiconductor nanorods.

The progression from quasi zero-dimensional (Q0D) nanoclusters to quasi one-dimensional (Q1D) nanorods, and, with increasing length, to nanowires, represents the most conceptually fundamental transition from the nanoscale to bulk-like length scales. This dimensionality crossover is particularly interesting, both scientifically and technologically, for inorganic semiconducting (ISC) materials, where striking concomitant changes in optoelectronic properties occur.(1,2) Such effects are most pronounced for ultra-thin(3) ISC nanorods/nanowires, where the confining and defective nature of the atomic structure become key.

Predicting transition pressures for obtaining nanoporous semiconductor polymorphs: oxides and chalcogenides of Zn, Cd and Mg.

The energy versus volume equations of state are calculated for seven known and hypothetical polymorphic forms of ZnX, CdX, and MgX (where X = O, S, Se, Te). From these data the phases of lowest enthalpy are extracted with respect to decreasing pressure starting at the ground state for all compositions. Following these paths of minimum enthalpy, with respect to the polymorphs considered, we predict the transition pressures required to convert the ground-state phase into the novel, as yet hypothetical, nanoporous SOD phase (an analogue of the silicate zeolite sodalite).