Experimental scientist and expert for research on nanostructured and interface determined materials and characterization by gas adsorption analysis combined with neutron and x-ray scattering techniques. Scientific focus are on fundamental research in the thermodynamics and structure of meso-scaled pore condensates as well as the sorption properties of gas storage materials and molecular sieves. Responsible at Helmholtz-Centre Berlin for scientific and technical user support at the neutron source BER-II and the synchrotron light source BESSY-II for sample environment concerning: high pressures and temperatures, controlled gas atmospheres, cryogen free cryostats, as well as for the operation of the complementary HZB user lab DEGAS for gas adsorption studies.

Publications

List of publications at HZB

2019


Badaczewski, F.; Loeh, M.O.; Pfaff, T.; Dobrotka, S.; Wallacher, D.; Clemens, D.; Metz, J.; Smarsly, B.: Peering into the structural evolution of glass-like carbons derived from phenolic resin by combining small-angle neutron scattering with an advanced evaluation method for wide-angle X-ray scattering. Carbon 141 (2019), p. 169-181


Ranieri, U.; Koza, M.M.; Kuhs, W.F.; Gaal, R.; Klotz, S.; Falenty, A.; Wallacher, D.; Ollivier, J.; Gillet, P.; Bove, L.E.: Quantum Dynamics of H2 and D2 Confined in Hydrate Structures as a Function of Pressure and Temperature. The Journal of Physical Chemistry C 123 (2019), p. 1888-1903

2018


Krause, S.; Bon, V.; Senkovska, I.; Többens, D.; Wallacher, D.; Pillai, R.; Maurin, G.; Kaskel, S.: The effect of crystallite size on pressure amplification in switchable porous solids. Nature Communications 9 (2018), p. 1573


Russina, M.; Guenther, G.; Grzimek, V.; Gainov, R.; Schlegel, M.; Drescher, L.; Kaulich, T.; Graf, W.; Urban, B.; Daske, A.; Grotjahn, K.; Hellhammer, R.; Buchert, G.; Kutz, H.; Rossa, L.; Sauer, O.-P.; Fromme, M.; Wallacher, D.; Kiefer, K.; Klemke, B.; Grimm, N.; Gerischer, S.; Tsapatsaris, N.; Rolfs, K.: Upgrade project NEAT'2016 at Helmholtz Zentrum Berlin - What can be done on the medium power neutron source. Physica B 551 (2018), p. 506-511

2017


Auer, H.; Wallacher, D.; Hansen, T.C.; Kohlmann, H.: In Situ Hydrogenation of the Zintl Phase SrGe. Inorganic Chemistry 56 (2017), p. 1072-1079


Busch, M.; Kityk, A.V.; Piecek, W.; Hofmann, T.; Wallacher, D.; Calus, S.; Kula, P.; Steinhart, M.; Eich, M.; Huber, P.: A ferroelectric liquid crystal confined in cylindrical nanopores: reversible smectic layer buckling, enhanced light rotation and extremely fast electro-optically active Goldstone excitations. Nanoscale 9 (2017), p. 19086-19099


Hofmann, T.; Wallacher, D.; Toft-Petersen, R.; Ryll, B.; Reehuis, M.; Habicht, K.: Phonons in mesoporous silicon: The influence of nanostructuring on the dispersion in the Debye regime. Microporous and Mesoporous Materials 243 (2017), p. 263-270


Jafta, C.J.; Petzold, A.; Risse, S.; Clemens, D.; Wallacher, D.; Goerigk, G.; Ballauff, M.: Correlating pore size and shape to local disorder in microporous carbon: A combined small angle neutron and X-ray scattering study. Carbon 123 (2017), p. 440-447


Klimkowicz, A.; Swierczek, K.; Zheng, K.; Wallacher, D.; Takasaki, A.: Oxygen release from BaLnMn2O6 (Ln: Pr, Nd, Y) under reducing conditions as studied by neutron diffraction. Journal of Materials Science 52 (2017), p. 6476-6485


Krause, S.; Bon, V.; Stoeck, U.; Senkovska, I.; Többens, D.; Wallacher, D.; Kaskel, S.: A Stimuli-Responsive Zirconium Metal-Organic Framework Based on Supermolecular Design. Angewandte Chemie - International Edition 56 (2017), p. 10676-10680


Krause, S.; Bon, V.; Stoeck, U.; Senkovska, I.; Többens, D.; Wallacher, D.; Kaskel, S.: A Stimuli-Responsive Zirconium Metal–Organic Framework Based on Supermolecular Design. Angewandte Chemie 129 (2017), p. 10816-10820


Schaber, J.; Krause, S.; Paasch, S.; Senkovska, I.; Bon, V.; Többens, D.; Wallacher, D.; Kaskel, S.; Brunner, E.: In Situ Monitoring of Unique Switching Transitions in the Pressure-Amplifying Flexible Framework Material DUT-49 by High-Pressure 129Xe NMR Spectroscopy. The Journal of Physical Chemistry C 121 (2017), p. 5195-5200

2016


Bon, V.; Kavoosi, N.; Senkovska, I.; Müller, P.; Schaber, J.; Wallacher, D.; Többens, D.M.; Mueller, U.; Kaskel, S.: Tuning the flexibility in MOFs by SBU functionalization. Dalton Transactions 45 (2016), p. 4407-4415


Borchardt, L.; Nickel, W.; Casco, M.; Senkovska, I.; Bon, V.; Wallacher, D.; Grimm, N.; Krause, S.; Silvestre-Albero, J.: Illuminating solid gas storage in confined spaces – methane hydrate formation in porous model carbons. Physical Chemistry Chemical Physics 18 (2016), p. 20607/1-8


Cairns, A.J.; Eckert, J.; Wojtas, L.; Thommes, M.; Wallacher, D.; Georgiev, P.A.; Forster, P.M.; Belmabkhout, Y.; Ollivier, J.; Eddaoudi, M.: Gaining Insights on the H2–Sorbent Interactions: Robust soc-MOF Platform as a Case Study. Chemistry of Materials 28 (2016), p. 7353-7361


Gruener, S.; Wallacher, D.; Greulich, S.; Busch, M.; Huber, P.: Hydraulic transport across hydrophilic and hydrophobic nanopores: Flow experiments with water and n-hexane. Physical Review E 93 (2016), p. 013102/1-13


Hofmann, T.; Wallacher, D.; Perlich, J.; Vayalil, S.K.; Huber, P.: Formation of Periodically Arranged Nanobubbles in Mesopores: Capillary Bridge Formation and Cavitation during Sorption and Solidification in an Hierarchical Porous SBA-15 Matrix. Langmuir 32 (2016), p. 2928-2936


Krause, S.; Bon, V.; Senkovska, I.; Stoeck, U.; Wallacher, D.; Többens, D.; Zander, S.; Pillai, R.S.; Maurin, G.; Coudert, F.X.; Kaskel, S.: A pressure-amplifying framework with negative gas adsorption transitions. Nature 532 (2016), p. 348-352


Schlegel, M.-C.; Többens, D.M.; Svetogorov, R.; Krüger, M.; Stock, N.; Reinsch, H.; Wallacher, D.; Stewart, R.; Russina, M.: Conformation-controlled hydrogen storage in the CAU-1 metal-organic framework. Physical Chemistry Chemical Physics 18 (2016), p. 29258-29267

2015


Bon, V.; Klein, N.; Senkovska, I.; Heerwig, A.; Getzschmann, J.; Wallacher, D.; Zizak, I.; Brzhezinskaya, M.; Müller, U.; Kaskel, S.: Exceptional adsorption-induced cluster and network deformation in the flexible metal–organic framework DUT-8(Ni) observed by in situ X-ray diffraction and EXAFS. Physical Chemistry Chemical Physics 17 (2015), p. 17471-17479


Bon, V.; Pallmann, J.; Eisbein, E.; Hoffmann, H.C.; Senkovska, I.; Schwedler, I.; Schneemann, A.; Henke, S.; Wallacher, D.; Fischer, R.A.; Seifert, G.; Brunner, E.; Kaskel, S.: Characteristics of flexibility in metal-organic framework solid solutions of composition [Zn2(BME-bdc)x(DB-bdc)2-xdabco]n: In situ powder X-ray diffraction. Microporous and Mesoporous Materials 216 (2015), p. 64–74


Kunkel, N.; Reichert, C.; Springborg, M.; Wallacher, D.; Kohlmann, H.: Hydrogenation properties of LixSr1-xAlSi studied by quantum-chemical methods (0≤x≤1) and in-situ neutron powder diffraction (x=1). Journal of Solid State Chemistry 211 (2015), p. 318-324


Mascotto, S.; Kuzmicz, D.; Wallacher, D.; Siebenbürger, M.; Clemens, D.; Risse, S.; Yuan, J.; Antonietti, M.; Ballauff, M.: Poly(ionic liquid)-derived nanoporous carbon analyzed by combination of gas physisorption and small-angle neutron scattering. Carbon 82 (2015), p. 425-435


Stoeckel, D.; Wallacher, D.; Zickler, G.; Thommes, M.; Smarsly, B.: Elucidating the Sorption Mechanism of Dibromomethane in Disordered Mesoporous Silica Adsorbents. Langmuir 31 (2015), p. 6332-6342


Weidemann, S.; Kockert, M.; Wallacher, D.; Ramsteiner, M.; Mogilatenko, A.; Rademann, K.; Fischer, S.F.: Controlled Pore Formation on Mesoporous Single Crystalline Silicon Nanowires: Threshold and Mechanisms. Journal of Nanomaterials 2015 (2015), p. 672305/1-11

2014


Bon, V.; Sekovska, I.; Wallacher, D.; Többens, D.; Zizak, I.; Feyerherm, R.; Mueller, U.; Kaskel, S.: In Situ Observation of Gating Phenomena in the Flexible Porous Coordination Polymer Zn2(BPnDC)2(bpy) (SNU-9) in a Combined Diffraction and Gas Adsorption Experiment. Inorganic Chemistry 53 (2014), p. 1513-1520


Bon, V.; Senkovska, I.; Wallacher, D.; Heerwig, A.; Klein, N.; Zizak, I.; Feyerherm, R.; Dudzik, E.; Kaskel, S.: In situ monitoring of structural changes during the adsorption on flexible porous coordination polymers by X-ray powder diffraction: Instrumentation and experimental results. Microporous and Mesoporous Materials 188 (2014), p. 190-195


Kojda, D.; Wallacher, D.; Baudoin, S.; Hansen, T.; Huber, P.; Hofmann, T.: Solid phases of spatially nanoconfined oxygen: A neutron scattering study. The Journal of Chemical Physics 140 (2014), p. 024705/1-9


Rother, G.; Vlcek, L.; Gruszkiewicz, M.S.; Chialvo, A.A.; Anovitz, L.M.; Banuelos, J.L.; Wallacher, D.; Grimm, N.; Cole, D.R.: Sorption Phase of Supercritical CO2 in Silica Aerogel: Experiments and Mesoscale Computer Simulations. The Journal of Physical Chemistry C 118 (2014), p. 15525-15533


Stoeckel, D.; Wallacher, D.; Zickler, G.A.; Perlich, J.; Tallarek, U.; Smarsly, B.M.: Coherent Analysis of Disordered Mesoporous Adsorbents using Small Angle X-Ray Scattering and Physisorption Experiments. Physical Chemistry Chemical Physics 16 (2014), p. 6583-6592

2013


Campbell, S.J.; Hofmann, M.; Mole, R.A.; Prokes, K.; Wallacher, D.; Wang, J.L.: Magnetic Order in YbMn2Si2 - Neutron Scattering Investigation. Journal of the Korean Physical Society 63 (2013), p. 314-319


Hofmann, T.; Kumar, P.; Enderle, M.; Wallacher, D.: Growth of Highly Oriented Deuterium Crystals in Silicon Nanochannels. Physical Review Letters 110 (2013), p. 065505/1-5


Jalarvo, N.; Casolo, S.; Aliouane, N.; Wallacher, D.; Lovvik, O.M.; Norby, T.: On the Complex Structural Picture of the Ionic Conductor Sr6Ta2O11. The Journal of Physical Chemistry C 117 (2013), p. 9543-9549


Karg, M.; Prévost, S.; Brandt, A.; Wallacher, D.; von Klitzing, R.; Hellweg, T.: Poly-NIPAM Microgels with Different Cross-Linker Densities : Scaling Behavior of the Network Fluctuations in the Vicinity of the Volume Phase Transition. In: Gabriele Sadowski ... [Ed.] : Intelligent hydrogels. Cham [u.a.]: Springer, 2013 (Progress in Colloid and Polymer Science ; 140). - ISBN 978-3-319-01682-5 , p. 63-76


Rother, G.; Ilton, E.S.; Wallacher, D.; Hauß, T.; Schaef, H.T.; Qafoku, O.; Rosso, K.M.; Felmy, A.R.; Krukowski, E.G.; Stack, A.G.; Grimm, N.; Bodnar, R.J.: CO2 Sorption to Subsingle Hydration Layer Montmorillonite Clay Studied by Excess Sorption and Neutron Diffraction Measurements. Environmental Science & Technology 47 (2013), p. 205-211


Stehle, R.; Goerigk, G.; Wallacher, D.; Ballauff, M.; Seiffert, S.: Small-angle X-ray scattering in droplet-based microfluidics. Lab on a Chip 13 (2013), p. 1529-1537

2012


Erko, M.; Wallacher, D.; Findenegg, G.H.; Paris, O.: Repeated sorption of water in SBA-15 investigated by means of in situ small-angle x-ray scattering. Journal of Physics / Condensed Matter 24 (2012), p. 284112/1-8


Erko, M.; Wallacher, D.; Hoell, A.; Hauß, T.; Zizak, I.; Paris, O.: Density minimum of confined water at low temperatures: a combined study by small-angle scattering of X-rays and neutrons. Physical Chemistry Chemical Physics 14 (2012), p. 3852-3858


Erko, M.; Wallacher, D.; Paris, O.: Deformation mechanism of nanoporous materials upon water freezing and melting. Applied Physics Letters 101 (2012), p. 181905/1-4


Gruszkiewicz, M.S.; Rother, G.; Wesolowski, D.J.; Cole, D.R.; Wallacher, D.: Direct Measurements of Pore Fluid Density by Vibrating Tube Densimetry. Langmuir 28 (2012), p. 5070-5078


Hofmann, T.; Wallacher, D.; Mayorova, M.; Zorn, R.; Frick, B.; Huber, P.: Molecular dynamics of n-hexane: A quasi-elastic neutron scattering study on the bulk and spatially nanochannel-confined liquid. The Journal of Chemical Physics 136 (2012), p. 124505/1-9


Kalisvaart, W.P.; Luber, E.J.; Poirier, E.; Harrower, C.T.; Teichert, A.; Wallacher, D.; Grimm, N.; Steitz, R.; Fritzsche, H.; Mitlin, D.: Probing the Room Temperature Deuterium Absorption Kinetics in Nanoscale Magnesium Based Hydrogen Storage Multilayers Using Neutron Reflectometry, X-ray Diffraction, and Atomic Force Microscopy. The Journal of Physical Chemistry C 116 (2012), p. 5868-5880


Kandemir, T.; Wallacher, D.; Hansen, T.; Liss, K.-D.; Naumann d'Alnoncourt, R.; Schlögl, R.; Behrens, M.: In situ neutron diffraction under high pressure - Providing an insight into working catalysts. Nuclear Instruments & Methods in Physics Research A 673 (2012), p. 51 - 55


Remhof, A.; Yan, Y.; Friedrichs, O.; Kim, J.W.; Mauron, Ph.; Borgschulte, A.; Wallacher, D.; Buchsteiner, A.; Hoser, A.; Oh, K.H.; Cho, Y.W.; Züttel, A.: Towards room temperature, direct, solvent free synthesis of tetraborohydrides. Journal of Physics : Conference Series 340 (2012), p. 012111/1-8


Rother, G.; Krukowski, E.G.; Wallacher, D.; Grimm, N.; Bodnar, R.J.; Cole, D.R.: Pore size effects on the sorption of supercritical CO2 in mesoporous CPG-10 silica. The Journal of Physical Chemistry C 116 (2012), p. 917-922


Sharifi, M.; Wallacher, D.; Wark, M.: Distribution of functional groups in periodic mesoporous organosilica materials studied by small-angle neutron scattering with in situ adsorption of nitrogen. Beilstein Journal of Nanotechnology 3 (2012), p. 428-437

2011


Demeter, J.; Teichert, A.; Kiefer, K.; Wallacher, D.; Ryll, H.; Menendez, E.; Paramanik, D.; Steitz, R.; Van Haesendonck, C.; Vantomme, A.; Temst, K.: Simultaneous polarized neutron reflectometry and anisotropic magnetoresistance measurements. Review of Scientific Instruments 82 (2011), p. 033902


Hauptvogel, I.M.; Biedermann, R.; Klein, N.; Senkovska, I.; Cadiau, A.; Wallacher, D.; Feyerherm, R.; Kaskel, S.: Flexible and Hydrophobic Zn-Based Metal-Organic Framework. Inorganic Chemistry 50 (2011), p. 8367-8374


Mihalik, M.; Pospisil, J.; Rudajevová, A.; Marti, X.; Wallacher, D.; Hoser, A.; Hofmann, T.; Divis, M.; Sechovský, V.: Structure phase transitions of polymorphic compounds with layered crystal structures: The REIr2Si2 case. Intermetallics 19 (2011), p. 1622 - 1626


Poirier, E.; Harrower, C.T.; Kalisvaart, P.; Bird, A.; Teichert, A.; Wallacher, D.; Grimm, N.; Steitz, R.; Mitlin, D.; Fritzsche, H.: Deuterium absorption in Mg70Al30 thin films with bilayer catalysts: A comparative neutron reflectometry study. Journal of Alloys and Compounds 509 (2011), p. 5466-5471


Sharifi, M.; Marschall, R.; Wilhelm, M.; Wallacher, D.; Wark, M.: Detection of Homogeneous Distribution of Functional Groups in Mesoporous Silica by Small Angle Neutron Scattering and in Situ Adsorption of Nitrogen or Water. Langmuir 27 (2011), p. 5516 - 5522

2010


Erko, M.; Wallacher, D.; Brandt, A.; Paris, O.: In-situ small-angle neutron scattering study of pore filling and pore Emptying in ordered mesoporous silica. Journal of Applied Crystallography 43 (2010), p. 1 - 7


Friedrichs, O.; Kim, J.W.; Remhof, A.; Wallacher, D.; Hoser, A.; Cho, Y.W.; Oh, K.H.; Züttel, A.: Core shell structure for solid gas synthesis of LiBD4. Physical Chemistry Chemical Physics 12 (2010), p. 4600 - 4603


Getzschmann, J.; Senkovska, I.; Wallacher, D.; Tovar, M.; Fairen-Jimenez, D.; Dueren, T.; van Baten, J.M.; Krishna, R.; Kaskel, S.: Methane storage mechanism in the metal-organic framework Cu3(btc)2: An in situ neutron diffraction study. Microporous and Mesoporous Materials 136 (2010), p. 50-58


Kandemir, T.; Wallacher, D.; Tovar, M.; Behrens, M.: In situ Neutron Diffraction Study of a Methanol Synthesis Catalyst under Working Conditions. Zeitschrift für Anorganische und Allgemeine Chemie 636 (2010), p. 2088


Martelli, P.; Remhof, A.; Borgschulte, A.; Mauron, P.; Wallacher, D.; Kemner, E.; Russina, M.; Pendolino, F.; Züttel, A.: BH4- Self-Diffusion in Liquid LiBH4. The Journal of Physical Chemistry A 114 (2010), p. 10117 - 10121


Mascotto, S.; Wallacher, D.; Kuschel, A.; Polarz, S.; Zickler, G.A.; Timmann, A.; Smarsly, B.M.: Adsorption in Periodically Ordered Mesoporous Organosilica Materials Studied by in Situ Small-Angle X-ray Scattering and Small-Angle Neutron Scattering. Langmuir 26 (2010), p. 6583-6592

2009


Friedrich, O.; Kim, J.W.; Remhof, A.; Buchter, F.; Borgschulte, A.; Wallacher, D.; Cho, Y.W.; Fichtner, M.; Oh, K.H.; Züttel, A.: The effect of Al on the hydrogen sorption mechanism of LiBH4. Physical Chemistry Chemical Physics 11 (2009), p. 1515-1520


Gruener, S. ; Hofmann, T. ; Wallacher, D. ; Kityk, A.V. ; Huber, P.: Capillary rise of water in hydrophilic nanopores. Physical Review E 79 (2009), p. 067301/1-4


Himsl, D. ; Wallacher, D. ; Hartmann, M: Improving the Hydrogen-Adsorption Properties of a Hydroxy-Modified MIL-53(Al) Structural Analogue by Lithium Doping. Angewandte Chemie / International Edition 48 (2009), p. 4639-4642


Jung, D.; Paradiso, M.; Wallacher, D.; Brandt, A.; Hartmann, M.: Formation of Cross-Linked Chloroperoxidase Aggregates in the Pores of Mesocellular Foams: Characterization by SANS and Catalytic Properties. ChemSusChem 2 (2009), p. 161-164


Mascotto, S.; Wallacher, D.; Brandt, A.; Hauss, T.; Thommes, M.; Zickler, G.A.; Funari, S.S.; Timmann, A.; Smarsly, B.M.: Analysis of Microporosity in Ordered Mesoporous Hierarchically Structured Silica by Combining Physisorption With in Situ Small-Angle Scattering (SAXS and SANS). Langmuir 25 (2009), p. 12670-12681


Remhof, A.; Friedrichs, O.; Buchter, F.; Mauron, Ph.; Kim, J.W.; Oh, K.H.; Buchsteiner, A.; Wallacher, D.; Züttel, A.: Hydrogen cycling behavior of LiBD4/Al studied by in situ neutron diffraction. Journal of Alloys and Compounds 484 (2009), p. 654-659

2008


Knorr, K.; Huber, P.; Wallacher, D.: Thermodynamic and Structural Investigations of Condensates of Small Molecules in Mesopores. Zeitschrift für Physikalische Chemie 222 (2008), p. 257-285


Remhof, A.; Friedrichs, O.; Buchter, F.; Mauron, Ph.; Züttel, A.; Wallacher, D.: Solid-state synthesis of LiBD4 observed by in situ neutron diffraction. Physical Chemistry Chemical Physics 10 (2008), p. 5859-5862


Wiedenmann, A. ; Keiderling, U. ; Meissner, M. ; Wallacher, D. ; Gähler, R. ; May, R.P. ; Prévost, S. ; Klokkenburg, M. ; Erné, B.H. ; Kohlbrecher, J.: Low-temperature dynamics of magnetic colloids studied by time-resolved small-angle neutron scattering. Physical Review B 77 (2008), p. 184417/1-11

2007


Sel, O; Brandt, A; Wallacher, D; Thommes, M; Smarsly, B : Pore hierarchy in mesoporous silicas evidenced by in-situ SANS during nitrogen physisorption. LANGMUIR 23 (2007), p. 4724-4727