We report on Cu nanowires as highly active and selective catalysts for electroreduction of CO at low overpotentials. The Cu nanowires were synthesized by reducing pregrown CuO nanowires, with the surface structures tailored by tuning the reduction conditions for improved catalytic performance. The optimized Cu nanowires achieved 65% faradaic efficiency (FE) for CO reduction and 50% FE toward production of ethanol at potentials more positive than −0.5 V (versus reversible hydrogen electrode, RHE). Structural analyses and computational simulations suggest that the CO reduction activity may be associated with the coordinately unsaturated (110) surface sites on the Cu nanowires.

The adsorption and decomposition of dimethyl methylphosphonate (DMMP), a chemical warfare agent (CWA) simulant, on size-selected molybdenum oxide trimer clusters, i.e. (MoO), was studied both experimentally and theoretically. X-ray photoelectron spectroscopy (XPS), temperature programmed reaction (TPR), and density functional theory (DFT)-based simulations were utilized in this study. The XPS and TPR results showed both, desorption of intact DMMP, and decomposition of DMMP through the elimination of methanol at elevated temperatures on (MoO) clusters. Theoretical investigation of DMMP on (MoO) clusters suggested that, in addition to pure (MoO) clusters, reduced molybdenum oxide clusters and hydroxylated molybdenum oxide clusters also play an important role in decomposing DMMP via a "reverse Mars-van Krevelen mechanism". The present study, which focused on oxide clusters, underlines the importance of surface defects, e.g., the oxygen vacancies and surface hydroxyls, in determining the reaction pathway of DMMP, in agreement with previous studies on thin films. In addition, the structural fluxionality and the Lewis acidity of molybdenum oxide clusters, i.e. (MoO), may make them good candidates for adsorption and decomposition of chemical warfare agents with similar structures to DMMP.

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Organophosphonates are used as chemical warfare agents, pesticides, and corrosion inhibitors. New materials for the sorption, detection, and decomposition of these compounds are urgently needed. To facilitate materials and application innovation, a better understanding of the interactions between organophosphonates and surfaces is required. To this end, we have used diffuse reflectance infrared Fourier transform spectroscopy to investigate the adsorption geometry of dimethyl methylphosphonate (DMMP) on MoO 3 , a material used in chemical warfare agent filtration devices. We further applied ambient pressure X-ray photoelectron spectroscopy and temperature programmed desorption to study the adsorption and desorption of DMMP. While DMMP adsorbs intact on MoO 3 , desorption depends on coverage and partial pressure. At low coverages under UHV conditions, the intact adsorption is reversible. Decomposition occurs with higher coverages, as evidenced by PCH x and PO x decomposition products on the MoO 3 surface. Heating under mTorr partial pressures of DMMP results in product accumulation.

This paper reports the synthesis of N, P, and Si tri-doped C (NPSiDC) using thiamine (a renewable resource material), silicone fluid, and ammonium polyphosphate. A one-pot microwave assisted method was utilized in synthesizing NPSiDC. The method is simple, rapid, and economical which does not employ any inert or reducing gases. Three variants of NPSiDCs were synthesized by varying the proportions of the precursor materials. NPSiDC-1 was found to have high specific surface area of 471 m 2 g −1 and a single point total pore volume of 0.25 cm 3 g −1 . Raman spectroscopy results revealed the presence of defects in an sp 2 C lattice. XPS analysis revealed the presence of N, P, Si, and O in C. NPSiDC-1 and NPSiDC-2 exhibited tremendous potential for supercapacitor applications with NPSiDC-1 recording highest specific capacitance value of 318 F g −1 in 6 M KOH. NPSiDCs were discovered to be electrochemically stable after 2000 cycles in 6 M KOH.