Surface Energy Minimization Research Articles

Hydrodynamics-dominated wetting phenomena on hybrid superhydrophobic surfaces

HypothesisBecause of rich local hysteresis, it is a challenge to determine the global minimum surface energy and consequently, the true apparent contact angle of a liquid droplet on chemically-heterogeneous, rough surfaces. Meanwhile, a specific type of wetting phenomena strongly dominated by the hydrodynamic process is expected to be resulted by the chemically-heterogeneous micro-structures, yet not well studied. SimulationsA series of micropatterned hybrid substrates, which have the same pillar dimensions but different pillar spacings, have been studied using continuum simulations. The hybrid feature of the micropatterns presented here has two defining facets: the pillar top-surface is highly hydrophilic (SiO2-based), while the pillar side-surface and substrate bottom surface are hydrophobic (Teflon). Different initializations of a 0.4 µL water droplet have been simulated to mimic the experimental measurements, i.e., releasing a stationary droplet near the substrate, impacting the droplet at various speeds, and setting an initial apparent contact angle of 90°. FindingsThe simulated contact angles agree with the experiments in the literature. Moreover, this study vividly depicts the hydrodynamics-dominated wetting processes, and captures multiple metastable Cassie-Baxter states. This research is applicable to the design of new hybrid superhydrophobic surfaces with special functionality, such as high controllability at varied hydrodynamic conditions.

Strongly confined localized surface plasmon resonance (LSPR) bands of Pt, AgPt, AgAuPt nanoparticles

Multi-metallic alloy nanoparticles (NPs) can enable the advanced applications in the energy, biology, electronics, optics and catalysis due to their multi-functionality, wide tunable range and electronic heterogeneity. In this work, various mono-, bi- and tri-metallic nanostructures composed of Ag, Au and Pt are demonstrated on transparent c-plane sapphire (0001) substrates and the corresponding morphological and optical characteristics are thoroughly investigated. The resulting Pt and AuPt NPs in this study demonstrate much enhanced LSPR responses as compared to the pure Pt NPs from the previous studies, which was contributed by the synergistic effect of Au and Pt and improved surface morphology. These results are sharply distinct in terms of surface morphology and elemental variability from those obtained by the dewetting of monometallic Ag, Au and Pt films under the similar growth conditions, which is due to the distinct dewetting kinetics of the bi-layer and tri-layer films. These NPs exhibit strongly enhanced localized surface plasmon resonance (LSPR) bands in the UV-VIS wavelengths such as dipolar, quadrupolar, multipolar and higher order resonance modes depending upon the size and elemental composition of NPs. The LSPR bands are much stronger with the high Ag content and gradually attenuated with the Ag sublimation. Furthermore, the VIS region LSPR bands are readily blue shifted along with the reduction of NP size. The Ag/Pt bi-layers and Ag/Au/Pt tri-layers are systematically dewetted and transformed into various AgPt and AgAuPt nanostructures such as networked, elongated and semispherical configurations by means of enhanced surface diffusion, intermixing and energy minimization along with the temperature control. The sublimation of Ag atoms plays a significant role in the structural and elemental composition of NPs such that more isolated and semispherical Pt and AuPt NPs are evolved from the AgPt and AgAuPt NPs respectively.

Composite nanoparticles: applications, creation mechanism, properties

Annotation This article presents data on the use of Janus-like and core-shell composite nanoparticles consisting of two substances—metal and semiconductor—in nanophotonics and spectroscopy. Investigations were carried out of the mechanism of formation of composite nanoparticles, based on the principle of minimum surface energy of the system and the results of molecular dynamics modelling. Integral representation was employed to analyse size distribution function of nanoparticles, and it was concluded that coagulation predominates during particle formation.

Researches on silane coupling agent treated AlN ceramic powder and fabrication of AlN/PTFE composites for microwave substrate applications

A study on water-resistant treatment of aluminum nitride (AlN) ceramic powder and the fabrication of AlN/PTFE(Polytetrafluoroethylene) composites for microwave substrate applications were described. AlN ceramic powder were modified by 1H,1H,2H,2H-perfluorooctyltriethoxysilane (F8261). The dosage of F8261 ranged from 0.8 to 1.6 wt%. FTIR and XPS were employed to characterize surface elements of aluminum nitride powder before and after modification. We soaked different AlN powder with deionized water, tested the pH of soaking liquid and observed changes of surface appearance via SEM. Among these modified AlN ceramic powder, 1.2 wt% F8261 modified AlN ceramic powder performed best. This powder not only had the maximum contact Angle (θ = 150.8o) and minimum surface energy (0.92 J/m2), but also had characteristic absorption peak of coupling agent (2922 cm−1, 2856 cm−1). Test results suggested that 1.2 wt% F8261 can make AlN powder obtain strong hydrophobicity, and greatly enhance the stability of AlN in wet environment. In another part, the optimal modified AlN powder and PTFE were combined, and the mass percentage of ceramics ranged from 15 to 45 wt%. Performance evaluation of above samples on the dielectric properties and thermal conductivity was accomplished by measuring their microstructure, moisture absorption and density. With 40 wt% filler, composites displayed satisfactory thermal conductivity (0.80 W/m K), reliable dielectric constant (er = 3.23), admissible dielectric loss (tan δ = 0.0059) and low water absorption (0.02%).

Solid state dewetting of Ag/Pt bilayers for the stronger localized surface plasmon resonance (LSPR) properties: The dynamic control of surface morphology and elemental composition of AgPt and Pt nanostructures by the auxiliary Ag layer

The modification and control of localized surface plasmon resonance (LSPR) properties of metallic nanoparticles (NPs) has become a vigorous research focus in various fields due to its wide range of applicability in various applications, which can be achieved by the control of surface morphology and elemental composition. In this paper, various configurations and compositions of AgPt and Pt NPs are demonstrated by the solid state dewetting using an auxiliary Ag layer on sapphire (0001) along with their strong dynamic LSPR properties. By the systematic control of Ag/Pt bilayer thickness and temperature, the interconnected AgPt nanoclusters at low temperature (<600 °C) and well-isolated pure Pt NPs at higher temperature (>650 °C) are obtained based on the enhanced diffusion, alloying, surface energy minimization and Ag sublimation. A strong LSPR response in the UV and VIS region is exhibited by the AgPt and Pt NPs depending on the alteration of size, shape, uniformity and elemental compositions. In particular, the AgPt NPs show the stronger plasmonic responses and it gradually attenuates with the sublimation of Ag atoms which results in the development of Pt NPs. In comparison with the previous study on the pure Pt NPs on sapphire, the Pt NPs in this study are significantly improved in terms of shape, size and spacing, whose LSPR responses are much stronger and dynamic. The auxiliary diffusion enhancement by Ag atoms leads to the rapid dewetting of AgPt NPs while the Ag sublimation assists the evolution of well-developed Pt NPs due to the vacancy creation and removal of material during mass transport. The tunability of surface morphologies and LSPR properties of AgPt and Pt NPs are systematically demonstrated by the methodical control of Ag/Pt bilayer thickness.

Facile chemical synthesis of nanosheets self-assembled hierarchical H2WO4 microspheres and their morphology-controlled thermal decomposition into WO3 microspheres

A controlled acidic precipitation is reported for the direct synthesis of nanosheets self-assembled hierarchical tungstic acid microspheres, and their annealing-dependent thermal conversion into WO3 microstructures is studied for the first time. The synthesis was carried out without the use of any structure directing agents and hydrothermal conditions. The microspheres were found to be consisting of many single-crystalline and highly oriented nanosheets that were hierarchically self-aggregated in spherical form for the minimization of surface energy. An experimentally validated time-dependent formation and growth mechanism was proposed for the development of microspheres. The characterization results indicated that the morphology-preserved thermal decomposition of H2WO4 into WO3 microspheres occurred at 400 °C, whereas a morphology distortion was noticed for the sample synthesized at 600 °C. The increase in annealing temperature further increased the crystallinity of WO3 without changing its monoclinic crystal structure. However, it has a diminishing effect in the specific surface area, pore size and pore volume of the annealed samples. Moreover, the adsorption of methylene blue in aqueous medium was carried out to evaluate its potential environmental application. The WO3 microspheres synthesized at 400 °C showed high adsorption capacity (63 mg/g) compared to the same at 600 °C (56 mg/g). The high activity could be ascribed to the synergistic effects of high surface area, low particle size, porosity, specific morphology and more negative zeta potential. The adsorption further followed pseudo-second-order kinetics with a best fit of the experimental and theoretical values.

Interface roughness and texture in Co/Cu multilayers with Ti buffer layer

In this study, we investigate the effect of Ti buffer layer on surface/interface roughness and texture of the Co/Cu multilayers. The Ti(0, 3nm)/[Co(5nm)/Cu(5nm)]5 multilayers were deposited by direct current magnetron sputtering. Experimental results show that the rough interfaces and coarse three-dimensional island structure present in Co/Cu multilayers, while the interface roughness decreases and smooth surface emerges in Ti/Co/Cu multilayers. Simulaneously, the sharp {111} fiber texture exists in Ti/Co/Cu multilayers, while the Co/Cu multilayers reveal a weak texture. Compared with the Co/Cu multilayers, inserting Ti buffer layer could decrease the interface energy and increase the wettability. In addition, the {111} fiber texture in FCC metal films corresponds to the most densely packed plane and the minimizing surface energy. Accompanied by the process of film nucleation, it could be concluded that the degree of interface roughness is related to the texture intensity in Co/Cu multilayers. The analyses of magnetic properties suggestes that the higher magnetic properties of Ti/Co/Cu multilayers are caused by the smooth interface and sharp {111} fiber texture.

Classification of the Morphologies and Related Crystal Phases of III–V Nanowires Based on the Surface Energy Analysis

Zincblende-wurtzite polytypism in III–V nanowires has been of great interest for a long time. However, full understanding and control over the crystal phase is still lacking. Here, we propose a model for the morphologies and related crystal phases of vapor–liquid–solid III–V nanowires by considering the minimum surface energies of different side wall facets as a function of the droplet contact angle. On the basis of the recent experimental data and earlier theoretical calculations of the surface energies, a simple classification of the possible growth modes is presented. It shows that the wurtzite phase forms in vertical nanowires at intermediate contact angles whereas the zincblende phase is predominant for vertical or inverse-tapered nanowires with a truncated top at larger contact angles. The small stable contact angle corresponds to faulted wurtzite–zincblende intermix. Pure zincblende phase is possible for even smaller contact angles only in the kinetic growth regimes. The wurtzite and zincblende dom...

Model of Advancing and Receding Contact Angles on Rough Surfaces

Contact angle hysteresis is a basic phenomenon in many industrial applications, such as material surface engineering and enhanced oil recovery. The mechanism of continuous change of the contact angle during hysteresis is not well understood and described, and it is also important to predict advancing and receding angles by the Young contact angle and surface roughness. In this work, a contact angle hysteresis model is developed based on several metastable contact angle models. The fraction difference between gas and liquid prefilling the solid grooves is assumed to be variable, so is the fraction difference of gas and liquid displaced by the other phase. Besides these two newly introduced variables, the solid area fraction, the ratio of the real surface area to the projected surface area, and the Young contact angle together influence the advancing and receding angles. Energy input or work is the external cause of hysteresis. The new variables are the intrinsic cause of hysteresis, enabling the continuous change of the contact angle and ensuring a minimal surface energy during hysteresis. The advancing and receding angles are explicitly expressed in a function of the factors mentioned above. The results from this model are in good coincidence with experiments from the literature. Through comparison, it is found that the model in this paper can be reduced as the Wenzel model, Cassie–Baxter model, etc., under special conditions.

Calculation of the Surface Energy of Metals: Agreement of the Thermodynamic Vacancy Model with the First-Principles Theory

The thermodynamic vacancy model (TVM) of surface energy (SE) leads to the formula of the linear dependence of the minimum SE value of the low-index fcc (111) and bcc (110) faces on half of the vacancy formation energy or the 1/6 part of the cohesive energy of metals. Comparison of the numerical values of SE calculated by the TVM method with those calculated by the DFT method for the same faces shows negative deviations of the latter (from 2 to 17%). Using the values of these deviations, the surface energy relaxation of metals was calculated with a maximum value for Au and Pt and a minimum value for Ag and Pd.

Numerical analysis of meniscus dynamics in monolayer-wick dropwise condensation

The effect of hydrophobic monolayer sintered-particle wick on the growth and departure of droplets in dropwise condensation over a vertical surface is analyzed numerically using the minimum meniscus surface energy principle and the direct simulation of the meniscus and heat transfer through the partially liquid-filled pores. The condensate fills the pores, increases the capillary pressure, and joins with the menisci from adjacent pores, leading to a droplet formation. The droplet growth is supported by liquid supply from the adjacent pores until the critical droplet departure volume is reached. The heat transfer rate is controlled by the average meniscus thickness, and the droplet surface coverage. Based on these and the plain–surface limit (for very small and very large particle diameter dp), a threshold band of dp is predicted below which the dropwise condensation rate is slightly enhanced compared to the plain, hydrophobic surface. The analysis explains the existing experimental results (and new augmented experimental results) and the challenges in further enhancing the dropwise condensation with surface microstructures.

Shape Engineering of InP Nanostructures by Selective Area Epitaxy.

Greater demand for III-V nanostructures with more sophisticated geometries other than nanowires is expected because of the recent intensive investigation of nanowire networks that show great potential in all-optical logic gates, nanoelectronics, and quantum computing. Here, we demonstrate highly uniform arrays of InP nanostructures with tunable shapes, such as membrane-, prism-, and ring-like shapes, which can be simultaneously grown by selective area epitaxy. Our in-depth investigation of shape evolution confirms that the shape is essentially determined by pattern confinement and the minimization of total surface energy. After growth optimization, all of the different InP nanostructures grown under the same growth conditions show perfect wurtzite structure regardless of the geometry and strong and homogeneous photon emission. This work expands the research field in terms of producing nanostructures with the desired shapes beyond the limits of nanowires to satisfy various requirements for nanoelectronics, optoelectronics, and quantum device applications.

Asymptotics of a catenoid liquid bridge between two spherical particles with different radii and contact angles

A liquid bridge between two neighboring particles is commonly observed in nature and various industrial processes. An accurate prediction of the profile of a liquid bridge is significantly important in particulate flows, while it is an analytically challenging task as well. In this paper, we develop an asymptotic solution for a catenoid liquid bridge profile, which is the minimal surface ensuring the minimum total surface energy. Our asymptotic solution is based on a rapid convergent predictor-corrector algorithm that considers different factors including boundary conditions, volume conservation, and geometrical relations while providing the relationship between the liquid bridge profile, bridge radius, half-filling angles, and creeping distances. Therefore, this asymptotic solution of the catenoid of the liquid bridge is applicable to general scenarios of any two neighboring particles of either equal or different sizes having identical or different contact angles. In order to validate the proposed asymptotic solution, we performed comprehensive experiments where the observed and predicted liquid bridge profiles and the resultant capillary forces from both the approaches are found closely matching. Moreover, we also investigate and report the influence of the radii ratio, contact angles, particle distances, and the liquid bridge volumes on its profiles.

Fabrication of Various Plasmonic Pt Nanostructures via Indium Assisted Solid-State Dewetting: From Small Nanoparticles to Widely Connected Networks.

In this paper, the modified solid-state dewetting (MSSD) of well-defined and various uniform Pt nanostructures is demonstrated by the auxiliary diffusion enhancement. The MSSD utilizes the introduction of metallic indium (In) layers with high diffusivity in between sapphire and platinum (Pt) layer, through which the global diffusion and dewetting of metallic atoms can be significantly enhanced. Subsequently, the In atoms can be sublimated from the NP matrix, resulting in the formation of pure Pt NPs. By the systematic control of In and Pt bi-layer thickness, various areal density, size and configuration of Pt NPs are demonstrated. The In2 nm/Pt2 nm bilayers establish very small and highly dense NPs throughout the temperature range due to the early maturation of growth. Intermediate size of NPs is demonstrated with the In45 nm/Pt15 nm bilayers with the much improved interparticle spacings by annealing between 650 and 900 °C for 450 s. Finally, the In30 nm/Pt30 nm bilayers demonstrate the widely connected network-like nanostructures. In addition, the finite difference time domain (FDTD) simulation is employed to exploit the local electric field distributions at resonance wavelengths. The dewetting characteristics of In/Pt bilayers is systematically controlled by the modifications of layer thickness and annealing temperature and is systematically described based on the diffusion of atoms, Rayleigh instability and surface energy minimization mechanism. The optical properties demonstrate dynamic and widely tunable localized surface plasmon resonance (LSPR) responses depending upon the various surface morphologies of Pt nanostructures.

The Influence of Grain Structure in SEI on Lithium Diffusivity and Electrodeposition in Li-Metal Batteries

Lithium metal batteries (LMBs) are among the most promising candidates for high energy density energy storage technologies [1]. In order to make LMBs commercially competitive with the other mature energy storage devices, several aspect hindering LMBs’ widespread application shall be resolved. In particular, the growth of Li dendrites can cause the LMBs performance decrease as well as severe safety problems associated with the short circuit. In this regard, the solid electrolyte interface (SEI), a nanoscopic layer formed between the metal electrode and the liquid electrolyte, controls the Li delivery to the surface of the negative electrode, where Li electrodeposition and dendrites formation occur. Thus, the understanding of Li diffusivity (e.g., pathways, energetics, etc.) through the SEI could enable the development of strategies towards safe, robust and long-lasting LMBs. For that reason, in this contribution, we present the results of a combined ab initio Density Functional Theory (DFT) calculations to study Li diffusion across the SEI and an extended phase-field model (PFM) for Li migration and electrodeposition, that is a step forward toward better understanding of Li dendrites formation and growth. The present DFT calculations are performed using the VASP (Vienna Ab initio Simulation Package) code [2] with the plane wave basis sets and the projector augmented wave (PAW) [3] pseudo-potentials in the framework of Perdew-Burke-Ernzerhof sol (PBEsol) generalized gradient approximation (GGA) [4]. The migration barriers and diffusion coefficients are evaluated using the Nudged Elastic Band (NEB) method as implemented in VASP. To perform the NEB calculations, the minimum energy surfaces of each grain structure in SEI are first created, using a slab method. Then, the grain boundary (GB) structures are generated by forming stable interfaces between the minimum energy surfaces. After identifying the thermodynamically stable GBs, the lithium diffusion channels through them are identified, and the NEB calculations are performed. In the current study, we examine the migration barriers through the GBs of two major inorganic SEI grain structures such as Li2O and LiF. From the migration barriers, it could be observed that the diffusion through the GBs are almost two orders of magnitude faster than the compared diffusion coefficients through the bulk of the SEI structures. The evaluated diffusion coefficients and the free energies are then used to derive the thermodynamically consistent free energy density needed for the PFM model to simulate the filament growth and understand the distribution and evolution of stress fields during Li electrodeposition. The PFM [5] is developed employing MOOSE framework [6]. In the present work the effect of solid electrolyte interface (SEI) on the evolution of Li electrodeposits is captured by modeling the GB structures in SEI and diffusion through these GBs. The results from PFM reveal thatthe anisotropic nature of Li presence at the metal/SEI interface leads to uneven electrodeposition at the Li metal surface. In addition, an elastic deformation energy of the Li solid phase is included in the free energy functional of the PFM, which allows for monitoring the stress field evolution and its influence on Li filaments structure evolution. The present results also show that a significant stress is observed at the root of the Li electrodeposits and the triple junction between the GBs. This observation can guide the development of the experimental strategies for suppression of Li dendrites by lowering the stress field and also provide us more valuable information on the role of SEI as a transport medium, providing more scope for improvement on battery safety and performance.

Size Controllable Metal Nanoparticles Anchored on Nitrogen Doped Carbon for Electrocatalytic Energy Conversion

AbstractMetal nanoparticles (NPs) are an important class of materials for electrocatalysis. Synthesis of metal NPs with uniform particle size below 10 nm without a capping agent is challenging due to the tendency of particle aggregation to minimize surface energy. Here we demonstrate that pyrolysis of a metal‐TCNQ (TCNQ−=tetracyanoquinodimethane radical anion) compound can produce metal NPs with controllable particle sizes anchored on nitrogen doped carbon (denoted as MetalNC). NiNC and CoNC derived from Ni‐TCNQ and Co‐TCNQ with Ni and Co particle sizes below 10 nm were successfully prepared. NiNC, with a particle size of 8.8 nm, showed excellent catalytic activity for hydrogen evolution in an alkaline medium, reaching a catalytic current density of 10 mA cm−2 at an overpotential of 230 mV. CoNC, with a particle size of 1.8 nm, exhibited the capability of producing syngas by electrocatalytic CO2 reduction over a wide potential range in an acetonitrile medium containing 0.3 M H2O. An artificial photosynthesis system based on CoNC achieved faradaic efficiencies of over 70 % for production of syngas and 22 % for formate. This work demonstrates a general strategy to synthesize size controllable metal NPs supported on carbon materials for electrocatalytic energy conversion.

Non-equilibrium growth model of fibrous mesocrystalline rutile TiO2 nanorods

Rutile TiO2 nanorods are used for hybrid solar cells, photocatalysis, gas sensing, and energy storage devices. Here, we report in detail on the hydrothermal growth mechanism of these nanorods. A typical feature of TiO2 nanorods is a fine structure consisting of a multitude of small fingers. Thus, these nanocrystals are rather mesocrystalline than single crystalline, which has a great impact on chemical, electronic, and optoelectronic properties. This feature is also found in some other nanocrystalline materials, which are relevant for technical applications. Consequently, the understanding and control of this fine structure is an essential key to tune and improve device performances. In this study, we introduce a material-independent thermodynamic model, which is able to describe the formation of such fine structures. The model is based on two competing thermodynamic processes, namely crystallization and surface energy minimization, which are essential for the growth of crystals. Thereby, a non-equilibrium state between the two processes triggers the bundling of thin nanocrystals and leads to the formation of mesocrystalline nanorods. Based on the model the dimensions of the fine structure can be controlled using different growth temperatures, HCl concentrations, and post annealing in accordance to experimental observations.

Existence results for the nonlinear Hodge minimal surface energy

Given a compact Riemannian manifold $$(M^n,g)$$ and a fixed cohomology class, $$[\alpha ^*] \in H^k(M)$$ , we consider the existence of a minimizer $$\alpha \in [\alpha ^*]$$ of the generalized minimal surface energy $$\int _M \sqrt{1+|\alpha |^2} dV_g$$ . When $$k = 1$$ , we prove the existence of unique minimizers for every cohomology class $$[\alpha ^*]$$ . Next, when $$k > 1$$ , we construct examples of singular solutions for finite cohomology class $$[\alpha ^*] \in H^k(S^k \times S^k,g)$$ , where g is conformal to the standard metric on $$S^k \times S^k$$ . Additionally, we show that when $$k=2$$ , these singular solutions are also solutions to the Born Infeld equation.

Step-flow growth in homoepitaxy of β-Ga2O3 (100)—The influence of the miscut direction and faceting

We present a systematic study on the influence of the miscut orientation on structural and electronic properties in the homoepitaxial growth on off-oriented β-Ga2O3 (100) substrates by metalorganic chemical vapour phase epitaxy. Layers grown on (100) substrates with 6° miscut toward the [001¯] direction show high electron mobilities of about 90 cm2 V−1 s−1 at electron concentrations in the range of 1–2 × 1018 cm−3, while layers grown under identical conditions but with 6° miscut toward the [001] direction exhibit low electron mobilities of around 10 cm2 V−1 s−1. By using high-resolution scanning transmission electron microscopy and atomic force microscopy, we find significant differences in the surface morphologies of the substrates after annealing and of the layers in dependence on their miscut direction. While substrates with miscuts toward [001¯] exhibit monolayer steps terminated by (2¯01) facets, mainly bilayer steps are found for miscuts toward [001]. Epitaxial growth on both substrates occurs in step-flow mode. However, while layers on substrates with a miscut toward [001¯] are free of structural defects, those on substrates with a miscut toward [001] are completely twinned with respect to the substrate and show stacking mismatch boundaries. This twinning is promoted at step edges by transformation of the (001)-B facets into (2¯01) facets. Density functional theory calculations of stoichiometric low index surfaces show that the (2¯01) facet has the lowest surface energy following the (100) surface. We conclude that facet transformation at the step edges is driven by surface energy minimization for the two kinds of crystallographically inequivalent miscut orientations in the monoclinic lattice of β-Ga2O3.

Phase-dependent structural and electrochemical properties of single crystalline MnS thin films deposited by DC reactive sputtering

Single crystalline α- and γ-MnS thin films have been deposited on Si and ITO substrates by reactive DC sputtering (Ar:H2S 2:1) of a manganese target for electrochemical energy storage application. We found that working pressure was one of the major parameters while optimizing the crystallinity of thin films, whereas the phase tuning (γ to α) was primarily controlled by temperature variations. The temperature was varied from RT to 450 °C, keeping the gas pressure constant at 10 mTorr optimized value, resulting in a transition between two different polymorphs of MnS as confirmed by XRD results. AFM and contact angle measurements were also performed to study the surface roughness, wetting properties, and surface energy calculations of prepared thin films. α-MnS films prepared at 400 °C were found to have a maximum contact angle of 118° and a minimum free surface energy (γSV) of 8.38 mN/m. Moreover, we have also studied the phase dependent electrochemical properties and found that γ-MnS thin films prepared at ambient substrate temperature displayed the highest specific capacitance of 178.3 F/g at a scan rate of 5 mV/s with superior charge-discharge rates in neutral electrolytes. As the substrate temperature was increased to 300 °C, we observed a continuous decrease in the respective specific capacitance values, and α-MnS electrodes were found to have a minimum specific capacitance of 120 F/g. The enhanced electrochemical performance of γ-MnS thin films can be attributed to the superior water interacting properties (θw = 90.4°) and its wurtzite structure, which enables easy penetration of electrolytes into the active materials.