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“Plasma-Catalytic Ammonia Reforming of Methane over Cu-Based Catalysts for the Production of HCN and H2at Reduced Temperature”. Yi Y, Wang X, Jafarzadeh A, Wang L, Liu P, He B, Yan J, Zhang R, Zhang H, Liu X, Guo H, Neyts EC, Bogaerts A, Acs Catalysis 11, 1765 (2021). http://doi.org/10.1021/acscatal.0c04940
Abstract: Industrial production of HCN from NH3 and CH4 not only uses precious Pt or Pt−Rh catalysts but also requires extremely high temperatures (∼1600 K). From an energetic, operational, and safety perspective, a drastic decrease in temperature is highly desirable. Here, we report ammonia reforming of methane for the production of HCN and H2 at 673 K by the combination of CH4/NH3 plasma and a supported Cu/silicalite-1 catalyst. 30% CH4 conversion has been achieved with 79% HCN selectivity. Catalyst characterization and plasma diagnostics reveal that the excellent reaction performance is attributed to metallic Cu active sites. In addition, we propose a possible reaction pathway, viz. E-R reactions with N, NH, NH2, and CH radicals produced in the plasma, for the production of HCN, based on density functional theory calculations. Importantly, the Cu/silicalite-1 catalyst costs less than 5% of the commercial Pt mesh catalyst.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 10.614
DOI: 10.1021/acscatal.0c04940
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“Fano resonances in bilayer phosphorene nanoring”. Zhang R, Wu Z, Li XJ, Li LL, Chen Q, Li Y-M, Peeters FM, Nanotechnology 29, 215202 (2018). http://doi.org/10.1088/1361-6528/AAB534
Abstract: Tunable transport properties and Fano resonances are predicted in a circular bilayer phosphorene nanoring. The conductance exhibits Fano resonances with varying incident energy and applied perpendicular magnetic field. These Fano resonance peaks can be accurately fitted with the well known Fano curves. When a magnetic field is applied to the nanoring, the conductance oscillates periodically with magnetic field which is reminiscent of the Aharonov-Bohm effect. Fano resonances are tightly related to the discrete states in the central nanoring, some of which are tunable by the magnetic field.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 3.44
Times cited: 4
DOI: 10.1088/1361-6528/AAB534
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“Exponentially selective molecular sieving through angstrom pores”. Sun PZ, Yagmurcukardes M, Zhang R, Kuang WJ, Lozada-Hidalgo M, Liu BL, Cheng H-M, Wang FC, Peeters FM, Grigorieva IV, Geim AK, Nature Communications 12, 7170 (2021). http://doi.org/10.1038/S41467-021-27347-9
Abstract: Two-dimensional crystals with angstrom-scale pores are widely considered as candidates for a next generation of molecular separation technologies aiming to provide extreme, exponentially large selectivity combined with high flow rates. No such pores have been demonstrated experimentally. Here we study gas transport through individual graphene pores created by low intensity exposure to low kV electrons. Helium and hydrogen permeate easily through these pores whereas larger species such as xenon and methane are practically blocked. Permeating gases experience activation barriers that increase quadratically with molecules' kinetic diameter, and the effective diameter of the created pores is estimated as similar to 2 angstroms, about one missing carbon ring. Our work reveals stringent conditions for achieving the long sought-after exponential selectivity using porous two-dimensional membranes and suggests limits on their possible performance. Two-dimensional membranes with angstrom-sized pores are predicted to combine high permeability with exceptional selectivity, but experimental demonstration has been challenging. Here the authors realize angstrom-sized pores in monolayer graphene and demonstrate gas transport with activation barriers increasing quadratically with the molecular kinetic diameter.
Keywords: A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Impact Factor: 12.124
Times cited: 28
DOI: 10.1038/S41467-021-27347-9
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