Theoretical Insights into the Structures and Capacitive Performances of Confined Ionic Liquids

Yang, Jie; Ding, Yajun; Lian, Cheng; Ying, Sanjiu; Liu, Honglai

doi:10.3390/polym12030722

Cited by 6 publications

(6 citation statements)

References 53 publications

(64 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Classical DFT has been applied to confined electrolytes 369,485,593−595 to explore charge inversion, 596 electrokinetic conversion efficiency, 597 charge neutrality breakdown, 598 the dynamics of concentrated electrolytes and ionic liquids, 599,600 and capacitance. 601…”

Section: Continuum Methodsmentioning

confidence: 99%

“…In addition, complex, yet accurate, classical DFT describes the local electrolyte structure within the EDL in terms of integrals of the local ionic densities. Classical DFT has been applied to confined electrolytes ,,− to explore charge inversion, electrokinetic conversion efficiency, charge neutrality breakdown, the dynamics of concentrated electrolytes and ionic liquids, , and capacitance …”

Section: Modeling Toolsmentioning

confidence: 99%

See 1 more Smart Citation

Fluids and Electrolytes under Confinement in Single-Digit Nanopores

et al. 2023

View full text Add to dashboard Cite

Confined fluids and electrolyte solutions in nanopores exhibit rich and surprising physics and chemistry that impact the mass transport and energy efficiency in many important natural systems and industrial applications. Existing theories often fail to predict the exotic effects observed in the narrowest of such pores, called single-digit nanopores (SDNs), which have diameters or conduit widths of less than 10 nm, and have only recently become accessible for experimental measurements. What SDNs reveal has been surprising, including a rapidly increasing number of examples such as extraordinarily fast water transport, distorted fluid-phase boundaries, strong ion-correlation and quantum effects, and dielectric anomalies that are not observed in larger pores. Exploiting these effects presents myriad opportunities in both basic and applied research that stand to impact a host of new technologies at the water−energy nexus, from new membranes for precise separations and water purification to new gas permeable materials for water electrolyzers and energy-storage devices. SDNs also present unique opportunities to achieve ultrasensitive and selective chemical sensing at the single-ion and single-molecule limit. In this review article, we summarize the progress on nanofluidics of SDNs, with a focus on the confinement effects that arise in these extremely narrow nanopores. The recent development of precision model systems, transformative experimental tools, and multiscale theories that have played enabling roles in advancing this frontier are reviewed. We also identify new knowledge gaps in our understanding of nanofluidic transport and provide an outlook for the future challenges and opportunities at this rapidly advancing frontier.

show abstract

Section: Continuum Methodsmentioning

confidence: 99%

Section: Modeling Toolsmentioning

confidence: 99%

Fluids and Electrolytes under Confinement in Single-Digit Nanopores

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Δμ i ex is the difference between the local excess chemical potential of ions in the slit pore and that in bulk. The detailed equations for excess chemical potential can be found in our previous publications. − , The electrostatic potential in the system satisfies the Poisson equation d 2 ϕ false( r false) d r 2 = − F ε 0 ε r ∑ i z i c i ( r ) and the boundary conditions ϕ false( 0 false) = ϕ false( D false) = E s ∂ ϕ ∂ r | r = D / 2 = 0 where F is the Faraday constant, ε 0 is the permittivity of vacuum, and ε r is the relative permittivity of water ( ε r = 78).…”

Section: Model and Methodsmentioning

confidence: 99%

“…The detailed equations for excess chemical potential can be found in our previous publications. [47][48][49]53 The electrostatic potential in the system satisfies the Poisson equation…”

Section: Classical Density Functional Theory (Cdft)mentioning

confidence: 99%

A Molecular Model for Understanding the Membrane Separation of Li⁺/Mg²⁺

Chen

Tao

Cheng

et al. 2023

Ind. Eng. Chem. Res.

Self Cite

View full text Add to dashboard Cite

High-purity lithium chloride is used in energy storage applications. A possible process to obtain it is through the separation of Li + and Mg 2+ ions from salt-lake brines with a high mass ratio of Mg 2+ /Li + . This separation can be achieved by nanofiltration and is not only important but also environmentally friendly. It requires a deep understanding of the competitive transport of Li + /Mg 2+ ions in the nanoscale. It is expected to be achieved by theoretical approaches since it remains a challenge for experimental observation. Here, a theoretical model combining the classical density functional theory (CDFT) with the Navier− Stokes (NS) equations was developed to study the selective separation of Li + /Mg 2+ ions in charged nanochannels. We found nanochannels have selectivity for the co-ions with a smaller radius and lower valence state, and the relationship between ion selectivity and surface potential is approximately exponential. Finally, we proposed an accurate empirical formula to characterize the influence of the pore structure, surface properties in the Li + /Mg 2+ separation performance, indicating that our work provides an effective approach to studying selective ionic transport.

show abstract

“…The CDFT is a convenient starting point for the microscopic structure and thermodynamic properties of inhomogeneous fluids [ 41 , 42 ]. It successfully accounts for the correlation and repulsive volume effects, and is widely applied to many fields of classical statistical mechanics, such as adsorption [ 43 , 44 , 45 , 46 ], phase transitions [ 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 ], inter-surface effective interactions [ 55 , 56 , 57 , 58 ], electrical double layer [ 6 , 59 , 60 , 61 , 62 , 63 ], polymer statistics [ 64 , 65 , 66 ], and solid [ 67 , 68 , 69 ].…”

Section: Introductionmentioning

confidence: 99%

On Capacitance and Energy Storage of Supercapacitor with Dielectric Constant Discontinuity

Zhou

2022

Nanomaterials

View full text Add to dashboard Cite

The classical density functional theory (CDFT) is applied to investigate influences of electrode dielectric constant on specific differential capacitance Cd and specific energy storage E of a cylindrical electrode pore electrical double layer. Throughout all calculations the electrode dielectric constant varies from 5, corresponding to a dielectric electrode, to εwr = 108 corresponding to a metal electrode. Main findings are summarized as below. (i): By using a far smaller value of the solution relative dielectric constant εr = 10, which matches with the reality of extremely narrow tube, one discloses that a rather high saturation voltage is needed to attain the saturation energy storage in the ultra-small pore. (ii): Use of a realistic low εr = 10 value brings two obvious effects. First, influence of bulk electrolyte concentration on the Cd is rather small except when the electrode potential is around the zero charge potential; influence on the E curve is almost unobservable. Second, there remain the Cd and E enhancing effects caused by counter-ion valency rise, but strength of the effects reduces greatly with dropping of the εr value; in contrast, the Cd and E reducing effects coming from the counter-ion size enhancing remain significant enough for the low εr value. (iii) A large value of electrode relative dielectric constant εrw always reduces both the capacitance and energy storage; moreover, the effect of the εrw value gets eventually unobservable for small enough pore when the εrw value is beyond the scope corresponding to dielectric electrode. It is analyzed that the above effects take their rise in the repulsion and attraction on the counter-ions and co-ions caused by the electrode bound charges and a strengthened inter-counterion electrostatic repulsion originated in the low εr value.

show abstract

Theoretical Insights into the Structures and Capacitive Performances of Confined Ionic Liquids

Cited by 6 publications

References 53 publications

Fluids and Electrolytes under Confinement in Single-Digit Nanopores

Fluids and Electrolytes under Confinement in Single-Digit Nanopores

A Molecular Model for Understanding the Membrane Separation of Li⁺/Mg²⁺

On Capacitance and Energy Storage of Supercapacitor with Dielectric Constant Discontinuity

Contact Info

Product

Resources

About

Theoretical Insights into the Structures and Capacitive Performances of Confined Ionic Liquids

Cited by 6 publications

References 53 publications

Fluids and Electrolytes under Confinement in Single-Digit Nanopores

Fluids and Electrolytes under Confinement in Single-Digit Nanopores

A Molecular Model for Understanding the Membrane Separation of Li+/Mg2+

On Capacitance and Energy Storage of Supercapacitor with Dielectric Constant Discontinuity

Contact Info

Product

Resources

About

A Molecular Model for Understanding the Membrane Separation of Li⁺/Mg²⁺