Faradaic deionization of brackish and sea water via pseudocapacitive cation and anion intercalation into few-layered molybdenum disulfide

This work establishes molybdenum disulfide/carbon nanotube electrodes for the desalination of high molar saline water. Capitalizing on the two-dimensional layered structure of MoS2, both cations and anions can be effectively removed from a feed water stream by faradaic ion intercalation. The approach is based on the setup of capacitive deionization (CDI), where an effluent water stream is desalinated via the formation of an electrical double-layer at two oppositely polarized carbon electrodes. Yet, CDI can only be effectively applied to low concentrated solutions due to the intrinsic limitation of the electrosorption mechanism. By replacing the conventional porous carbon with MoS2/CNT binder-free electrodes, deionization of sodium and chloride ions was achieved by ion intercalation instead of ion electrosorption. This enabled stable desalination performance over 25 cycles in various molar concentrations, with salt adsorption capacities of 10, 13, 18, and 25 mg g−1 in 5, 25, 100, and 500 mM NaCl aqueous solutions, respectively. This novel approach of faradaic deionization (FDI) paves the way towards a more energy-efficient desalination of brackish water and even sea water.

[1]  Volker Presser,et al.  Water desalination via capacitive deionization : What is it and what can we expect from it? , 2015 .

[2]  V. Presser,et al.  Graphitization as a Universal Tool to Tailor the Potential‐Dependent Capacitance of Carbon Supercapacitors , 2014 .

[3]  Choonsoo Kim,et al.  Na2FeP2O7 as a Novel Material for Hybrid Capacitive Deionization , 2016 .

[4]  D. Aurbach,et al.  The electrochemistry of activated carbonaceous materials: past, present, and future , 2011 .

[5]  V. Presser,et al.  MXene as a novel intercalation-type pseudocapacitive cathode and anode for capacitive deionization , 2016 .

[6]  Volker Presser,et al.  Enhanced performance stability of carbon/titania hybrid electrodes during capacitive deionization of oxygen saturated saline water , 2017 .

[7]  Hugen Yan,et al.  Anomalous lattice vibrations of single- and few-layer MoS2. , 2010, ACS nano.

[8]  Volker Presser,et al.  Capacitive deionization in organic solutions: case study using propylene carbonate , 2016 .

[9]  Bo Liu,et al.  High yield exfoliation of two-dimensional chalcogenides using sodium naphthalenide , 2014, Nature Communications.

[10]  D. A. Brownson,et al.  2D molybdenum disulphide (2D-MoS2) modified electrodes explored towards the oxygen reduction reaction. , 2016, Nanoscale.

[11]  J. Georgiadis,et al.  Science and technology for water purification in the coming decades , 2008, Nature.

[12]  Liquan Chen,et al.  Atomic-scale clarification of structural transition of MoS₂ upon sodium intercalation. , 2014, ACS nano.

[13]  P. M. Biesheuvel,et al.  Complementary surface charge for enhanced capacitive deionization. , 2016, Water research.

[14]  Gyeong Sook Bang,et al.  Effective liquid-phase exfoliation and sodium ion battery application of MoS2 nanosheets. , 2014, ACS applied materials & interfaces.

[15]  U. Waghmare,et al.  Extraordinary attributes of 2-dimensional MoS2 nanosheets , 2014 .

[16]  Volker Presser,et al.  Review on the science and technology of water desalination by capacitive deionization , 2013 .

[17]  Choonsoo Kim,et al.  Hybrid capacitive deionization to enhance the desalination performance of capacitive techniques , 2014 .

[18]  M. Chhowalla,et al.  Metallic 1T phase MoS2 nanosheets as supercapacitor electrode materials. , 2015, Nature nanotechnology.

[19]  Y. Oren,et al.  Capacitive deionization (CDI) for desalination and water treatment — past, present and future (a review) , 2008 .

[20]  Dominique Baillargeat,et al.  From Bulk to Monolayer MoS2: Evolution of Raman Scattering , 2012 .

[21]  K. Krishnamoorthy,et al.  Mechanically delaminated few layered MoS 2 nanosheets based high performance wire type solid-state symmetric supercapacitors , 2016 .

[22]  V. Presser,et al.  Improved capacitive deionization performance of mixed hydrophobic/hydrophilic activated carbon electrodes , 2016, Journal of physics. Condensed matter : an Institute of Physics journal.

[23]  M. Elimelech,et al.  The Future of Seawater Desalination: Energy, Technology, and the Environment , 2011, Science.

[24]  Xiulei Ji,et al.  Na+ intercalation pseudocapacitance in graphene-coupled titanium oxide enabling ultra-fast sodium storage and long-term cycling , 2015, Nature Communications.

[25]  T. Itoh,et al.  In Situ Visualization of Lithium Ion Intercalation into MoS2 Single Crystals using Differential Optical Microscopy with Atomic Layer Resolution. , 2016, Journal of the American Chemical Society.

[26]  Thomas Melin,et al.  State-of-the-art of reverse osmosis desalination , 2007 .

[27]  A. Soper,et al.  Hydration of sodium, potassium, and chloride ions in solution and the concept of structure maker/breaker. , 2007, The journal of physical chemistry. B.

[28]  D. Aurbach,et al.  Novel in situ multiharmonic EQCM-D approach to characterize complex carbon pore architectures for capacitive deionization of brackish water , 2016, Journal of physics. Condensed matter : an Institute of Physics journal.

[29]  M. Diallo,et al.  Nanomaterials and Water Purification: Opportunities and Challenges , 2005 .

[30]  Bruce Dunn,et al.  Efficient storage mechanisms for building better supercapacitors , 2016, Nature Energy.

[31]  H. Ezzat Khalifa,et al.  Tables of the Dynamic and Kinematic Viscosity of Aqueous KCl Solutions in the Temperature Range 25-150 C and the Pressure Range 0.1-35 MPa, , 1981 .

[32]  Yi Cui,et al.  A desalination battery. , 2012, Nano letters.

[33]  Majid Beidaghi,et al.  Solving the Capacitive Paradox of 2D MXene using Electrochemical Quartz‐Crystal Admittance and In Situ Electronic Conductance Measurements , 2015 .

[34]  Xia Cao,et al.  Chemically exfoliated MoS2 for capacitive deionization of saline water , 2017 .

[35]  Rylan Dmello,et al.  Na-Ion Desalination (NID) Enabled by Na-Blocking Membranes and Symmetric Na-Intercalation: Porous-Electrode Modeling , 2016 .

[36]  Fei Meng,et al.  Enhanced hydrogen evolution catalysis from chemically exfoliated metallic MoS2 nanosheets. , 2013, Journal of the American Chemical Society.

[37]  J. Greeley,et al.  Effect of Concentration on the Energetics and Dynamics of Li Ion Transport in Anatase and Amorphous TiO2 , 2011 .

[38]  Gerbrand Ceder,et al.  Lithium diffusion mechanisms in layered intercalation compounds , 2001 .

[39]  V. Presser,et al.  Quantification of ion confinement and desolvation in nanoporous carbon supercapacitors with modelling and in situ X-ray scattering , 2017, Nature Energy.

[40]  Heidelberg,et al.  Attractive forces in microporous carbon electrodes for capacitive deionization , 2013, Journal of Solid State Electrochemistry.

[41]  Na Liu,et al.  Large-area atomically thin MoS2 nanosheets prepared using electrochemical exfoliation. , 2014, ACS nano.

[42]  Jeffrey W. Long,et al.  To Be or Not To Be Pseudocapacitive , 2015 .

[43]  P. M. Biesheuvel,et al.  Energy consumption and constant current operation in membrane capacitive deionization , 2012 .

[44]  Yury Gogotsi,et al.  2D metal carbides and nitrides (MXenes) for energy storage , 2017 .

[45]  Yong Liu,et al.  Review on carbon-based composite materials for capacitive deionization , 2015 .

[46]  V. Afanasiev,et al.  State of hydration shells of sodium chloride in aqueous solutions in a wide concentration range at 273.15-373.15 K. , 2009, Journal of Physical Chemistry B.

[47]  E. Teller,et al.  ADSORPTION OF GASES IN MULTIMOLECULAR LAYERS , 1938 .