• Alumina scale composition and growth rate in distribution pipes 

      Haugland, Ingrid Bokn; Kjos, Ole Sigmund; Røyset, Arne Karstein; Vullum, Per Erik; Aarhaug, Thor Anders; Halstensen, Maths (The Minerals, Metals & Materials Series;2367-1181, Peer reviewed; Journal article, 2019)
      Scaling in distribution pipes for secondary alumina is a major issue in aluminium smelters. The scale is formed inside the distribution pipes, and gradually reduces the cross section that is available for alumina transport. ...
    • Compositional and structural properties of pulsed laser-deposited ZnS:Cr films 

      Nematollahi, Mohammadreza; Yang, Xiaodong; Seim, Eivind; Vullum, Per Erik; Holmestad, Randi; Gibson, Ursula; Reenaas, Turid Worren (Peer reviewed; Journal article, 2016)
      We present the properties of Cr-doped zinc sulfide (ZnS:Cr) films deposited on Si(100) by pulsed laser deposition. The films are studied for solar cell applications, and to obtain a high absorption, a high Cr content ...
    • Conductivity control via minimally invasive anti-Frenkel defects in a functional oxide 

      Evans, Donald; Holstad, Theodor Secanell; Mosberg, Aleksander Buseth; Småbråten, Didrik Rene; Vullum, Per Erik; Dadlani, Anup; Shapovalov, Konstantin; Yan, Zewu; Bourret, Edith; Gao, David Zhe; Akola, Jaakko; Torgersen, Jan; Van Helvoort, Antonius; Selbach, Sverre Magnus; Meier, Dennis (Peer reviewed; Journal article, 2020)
      Utilizing quantum effects in complex oxides, such as magnetism, multiferroicity and superconductivity, requires atomic-level control of the material’s structure and composition. In contrast, the continuous conductivity ...
    • Critically testing olivine-hosted putative martian biosignatures in the Yamato 000593 meteorite - Geobiological implications 

      McLoughlin, Nicola; Grosch, Eugene Gerald; Vullum, Per Erik; Guagliardo, Paul; Saunders, Martin; Wacey, David (Journal article; Peer reviewed, 2019)
      On rocky planets such as Earth and Mars the serpentinization of olivine in ultramafic crust produces hydrogen that can act as a potential energy source for life. Direct evidence of fluid–rock interaction on Mars comes from ...
    • Detecting minute amounts of nitrogen in GaNAs thin films using STEM and CBED 

      Vatanparast, Maryam; Shao, Yu-Tsun; Rajpalke, Mohana; Fimland, Bjørn-Ove; Reenaas, Turid Dory; Holmestad, Randi; Vullum, Per Erik; Zuo, Jian Min (Peer reviewed; Journal article, 2021)
      Nitrogen (N) is a common element added to GaAs for band gap engineering and strain compensation. However, detection of small amounts of N is difficult for electron microscopy as well as for other chemical analysis techniques. ...
    • Direct Observation of Charge Transfer between NOx and Monolayer MoS2 by Operando Scanning Photoelectron Microscopy 

      Jensen, Ingvild Julie Thue; Ali, Ayaz; Zeller, Patrick; Amati, Matteo; Schrade, Matthias; Vullum, Per Erik; Benthem, Marta; Bisht, Prashant; Taniguchi, Takashi; Watanabe, Kenji; Mehta, Bodh R.; Gregoratti, Luca; Belle, Branson (Peer reviewed; Journal article, 2021)
      Atomically thin transition-metal dichalcogenides (MoS2, WSe2, etc.) have long been touted as promising materials for gas detection because of their tunable band gaps; however, the sensing mechanism, based on a charge-transfer ...
    • Effects of metal dusting relevant exposures of alloy 601 surfaces on carbon formation and oxide development 

      Guo, Xiaoyang; Vanhaecke, Estelle Marie M.; Vullum, Per Erik; Ma, Jianyu; Panditha Vidana, Daham Sanjaya Gunawardana; Walmsley, John; Chen, De; Venvik, Hilde Johnsen (Peer reviewed; Journal article, 2020)
      Ni and Fe are excellent catalysts for carbon formation, and industrial alloys are therefore susceptible to metal dusting corrosion; a costly issue in e.g. synthesis gas manufacture. The objective of this work is to better ...
    • Flame spray pyrolysis of electrode materials for energy applications 

      Dahl, Paul Inge; Thomassen, Magnus Skinlo; Rausseo, Luis César Colmenares; Barnet, Alejandro; Lomas, Scott; Vullum, Per Erik; Hanetho, Sidsel Meli; Mokkelbost, Tommy (Peer reviewed; Journal article, 2015)
      Flame spray pyrolysis (FSP) was applied to produce nanopowders of Ti1-xMxO2 and Sn1-xMxO2, where x = 0.05 and M = Nb/Sb, for use as catalyst support materials in PEM fuel cells/ electrolysers. FSP powders in the SnO2-IrO2 ...
    • Flame spray pyrolysis of tin oxide-based Pt catalysts for PEM fuel cell applications 

      Dahl, Paul Inge; Rausseo, Luis César Colmenares; Barnett, Alejandro; Lomas, Scott; Vullum, Per Erik; Kvello, Jannicke Hatlø; Tolchard, Julian R; Hanetho, Sidsel Meli; Mokkelbost, Tommy (Journal article; Peer reviewed, 2017)
    • GaAs/AlGaAs Nanowire Array Solar Cell Grown on Si with Ultrahigh Power-per-Weight Ratio 

      Mukherjee, Anjan; Ren, Dingding; Vullum, Per Erik; Huh, Junghwan; Fimland, Bjørn-Ove; Weman, Helge (Peer reviewed; Journal article, 2021)
      Here we demonstrate a more effective use of III–V photoconversion material to achieve an ultrahigh power-per-weight ratio from a solar cell utilizing an axial p-i-n junction GaAs/AlGaAs nanowire (NW) array grown by molecular ...
    • GaN/AlGaN nanocolumn ultraviolet light-emitting diode using double-Layer graphene as substrate and transparent electrode 

      Høiaas, Ida Marie; Liudi Mulyo, Andreas; Vullum, Per Erik; Kim, Dong Chul; Ahtapodov, Lyubomir; Fimland, Bjørn-Ove; Kishino, Katsumi; Weman, Helge (Peer reviewed; Journal article, 2019)
      The many outstanding properties of graphene have impressed and intrigued scientists for the last few decades. Its transparency to light of all wavelengths combined with a low sheet resistance makes it a promising electrode ...
    • Graphene-Based Transparent Conducting Substrates for GaN/AlGaN Nanocolumn Flip-Chip Ultraviolet Light-Emitting Diodes 

      Liudi Mulyo, Andreas; Mukherjee, Anjan; Høiaas, Ida Marie; Ahtapodov, Lyubomir; Nilsen, Tron Arne; Toftevaag, Håvard Hem; Vullum, Per Erik; Kishino, Katsumi; Weman, Helge; Fimland, Bjørn-Ove (Peer reviewed; Journal article, 2021)
      Flip-chip ultraviolet light-emitting diodes based on self-assembled GaN/AlGaN nanocolumns have been fabricated, exploiting single-layer graphene not only as a growth substrate but also as a transparent conducting electrode. ...
    • High capacity Mg batteries based on surface-controlled electrochemical reactions 

      Wang, Lu; Vullum, Per Erik; Asheim, Karina; Wang, Xuehang; Svensson, Ann Mari; Vullum-Bruer, Fride (Journal article; Peer reviewed, 2018)
      Mg batteries are one of several new battery technologies expected to partially substitute lithium-based batteries in the future due to the lower cost and higher safety. However, the development of Mg batteries has been ...
    • High interfacial charge storage capability of carbonaceous cathodes for Mg batteries 

      Wang, Lu; Jiang, Bo; Vullum, Per Erik; Svensson, Ann Mari; Erbe, Andreas; Selbach, Sverre Magnus; Xu, Huailiang; Vullum-Bruer, Fride (Peer reviewed; Journal article, 2018)
      A rechargeable Mg battery where the capacity mainly originates from reversible reactions occurring at the electrode/electrolyte interface efficiently avoids the challenge of sluggish Mg intercalation encountered in ...
    • High-Performance and Ultralow-Noise Two-Dimensional Heterostructure Field-Effect Transistors with One-Dimensional Electrical Contacts 

      Behera, Aroop; Harris, Charles; Pete, Douglas; Delker, Collin; Vullum, Per Erik; Benthem, Marta; Koybasi, Ozhan; Taniguchi, Takashi; Watanabe, Kenji; Belle, Branson; Das, Suprem (Peer reviewed; Journal article, 2021)
      Two-dimensional heterostructure field-effect transistors (2D-HFETs) with one-dimensional electrical contacts to atomically thin channels have recently shown great device performance, such as reduced contact resistance, ...
    • Improved cyclability of Nickel-rich layered oxides 

      Wagner, Nils Peter; Tolchard, Julian R; Tron, Artur; Pollen, Harald Norrud; Gaertner, Heiko; Vullum, Per Erik (Peer reviewed; Journal article, 2020)
      This study compares the physico- and electro- chemical properties of LiNi0.8Mn0.10Co0.1O2 (NMC811) and LiNi0.83Mn0.06Co0.09Al0.1O2 (NMCA) prepared by an oxalic acid co-precipitation. Deposition of a SiO2 surface coating ...
    • Improved electrochemical performance and solid electrolyte interphase properties of electrolytes based on lithium bis(fluorosulfonyl)imide for high content silicon anodes 

      Asheim, Karina; Vullum, Per Erik; Wagner, Nils Peter; Andersen, Hanne Flåten; Mæhlen, Jan Petter; Svensson, Ann Mari (Peer reviewed; Journal article, 2022)
      Electrodes containing 60 wt% micron-sized silicon were investigated with electrolytes containing carbonate solvents and either LiPF6 or lithium bis(fluorosulfonyl)imide (LiFSI) salt. The electrodes showed improved performance, ...
    • The influence of AlN buffer layer on the growth of self-assembled GaN nanocolumns on graphene 

      Liudi Mulyo, Andreas; Rajpalke, Mohana; Vullum, Per Erik; Weman, Helge; Kishino, Katsumi; Fimland, Bjørn-Ove (Peer reviewed; Journal article, 2020)
      GaN nanocolumns were synthesized on single-layer graphene via radio-frequency plasma-assisted molecular beam epitaxy, using a thin migration-enhanced epitaxy (MEE) AlN buffer layer as nucleation sites. Due to the weak ...
    • Inhibition of metal dusting corrosion on Fe-based alloy by combined near surface severe plastic deformation (NS-SPD) and thermochemical treatment 

      Guo, Xiaoyang; Vullum, Per Erik; Venvik, Hilde Johnsen (Peer reviewed; Journal article, 2021)
      Combined NS-SPD and thermochemical treatment has been used to improve the metal dusting corrosion resistance of Incoloy 800. After testing under infinite carbon activity for 20−100 h, carbon was not found in the NS-SPD ...
    • Inside the electrode: Looking at cycling products in Li/O2 batteries 

      Augustin, Matthias; Vullum, Per Erik; Vullum-Bruer, Fride; Svensson, Ann Mari (Journal article; Peer reviewed, 2019)
      This work investigates the impact of electrochemical reactions and products on discharge capacity and cycling stability with electrolytes based on two common solvents – tetraethylene glycol dimethyl ether (TEGDME) and ...