Multilayer Conductive Hybrid Nanosheets as Versatile Hybridization Matrices for Optimizing the Defect Structure, Structural Ordering, and Energy‐Functionality of Nanostructured Materials

Abstract

The hybridization of conductive nanospecies has garnered significant research interest because of its high efficacy in improving the diverse functionalities of nanostructured materials. In this study, a novel synthetic strategy is developed to optimize the defect structure, structural ordering, and energy‐related functionality of nanostructured‐materials by employing a multilayer multicomponent two‐dimenstional (2D) graphene/metal oxide/graphene nanosheet (NS) as a versatile hybridization matrix. The hybridization of the robust trilayer, polydiallyldiammonium (PDDA)‐anchored reduced‐graphene oxide (prGO)/metal oxide/prGO NS effectively enhance the structural ordering and porosity of the hybridized MoS2/MnO2 NS through suppression of defect formation and tight stacking. In comparison with monolayer rGO/RuO2 NS‐based homologs, the 2D superlattice trilayer prGO/RuO2/prGO NS hybrids deliver better functionalities as a hydrogen evolution electrocatalyst and as a supercapacitor electrode, demonstrating the merits of hybridization with multilayer NSs. The advantages of using multilayer multicomponent conductive NSs as hybridization matrices arise from the enhancement of charge and mass transport through the layer flattening or defect suppression of the hybridized NSs and the increase in porosity, as evidenced by density functional theory calculations. Finally, the universal utility of multilayer NSs is confirmed by investigating the strong effect of the stacking order on the electrocatalytic functionality of MoS2/rGO/RuO2 films fabricated through layer‐by‐layer deposition.

Superlattice-Like Co-Doped Mn Oxide and NiFe Hydroxide Nanosheets toward an Energetic Oxygen Evolution Reaction

“…With respect to the MnCo/NiFe (Figure g), the wrinkle at the edges of the nanosheets revealed an obvious layered structure. , Figure h showed the clear fringes with a repeating spacing of ∼1 nm. , Such the result confirmed the alternately stacked monolayer nanosheet of MnCo-O (0.52 nm) and NiFe-OH (0.48 nm). The hybrid SAED pattern with spots (MnCo-O) plus diffraction rings (NiFe-OH) further demonstrated the formation of superlattice structure. , The mapping images in Figure i exhibited the uniform distribution of Mn, Co, Ni, and Fe elements in MnCo/NiFe …”

“…Figure S2c revealed the scaly-like shape of DS-NiFe LDH, and such a sample also can be exfoliated to NiFe-OH monolayer nanosheets (Figure d) under shaking. Due to the opposite charges of MnCo-O (negative) and NiFe-OH (positive) nanosheets, they could attract each other to form the alternating layered structure of MnCo/NiFe (top view of Figure e; side view of Figure h). , …”

“…Using linear fitting, the C dl values of MnCo-O, NiFe-OH, and MnCo/NiFe were calculated as 1.17, 0.88, and 0.30 mF cm –2 , respectively. The relatively high C dl values of MnCo-O and NiFe-OH could be attributed to their large exposed surface from monolayer nanosheets than from the alternating stacked layers of MnCo/NiFe …”

Steric Effects in the Deposition Mode and Drug-Delivering Efficiency of Nanocapsule-Based Multilayer Films

“… 33 Among the variations, the charge density of the film constituents was considered one of the most important factors controlling drug release profiles and post-assembly entrapment. 34 For instance, the motion speed of the molecules within the solid films was increased as the ionization degree of polyamine species was reduced to a value below 70%. 29 …”

Influence of Monolayered RuO2 Nanosheets and Co2+ Ion Linkers in Improving the Electrocatalytic Performance of MoS2 Nanoflowers

“…As a result of the crisis of increasing fossil fuel depletion and CO 2 emissions, extensive research on the development of economically feasible production methods for renewable energy is being conducted. , Although hydrogen energy is considered an efficient alternative to conventional fossil fuels, − hydrogen production is currently achieved mainly by the steam reformation process of CH 4 that also releases an excessive amount of CO 2 . To address the detrimental climate change caused by this commercialized process, it is necessary to establish an eco-friendly carbon-free hydrogen production technique, such as electrochemical water splitting. − The development of high-performance electrocatalysts for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is indispensable to accomplish effective water splitting. − One of the most promising classes of materials emerging as viable candidates for efficient HER electrocatalysis is nanostructured transition metal dichalcogenides, like MoS 2 . − The morphological control of nanostructured MoS 2 has been documented to be useful in increasing the HER electrocatalytic activity through the increase of adequate edge sites active for hydrogen adsorption and HER. − In addition to such morphology control, coupling with conductive nanostructures could provide an alternative means to improve the HER performance of MoS 2 , owing to the enhancement in electrical conductivity and the mass transport property. , The excellent electrical conduction renders graphene a powerful hybridization matrix for facilitating the charge/mass transport of MoS 2 nanostructures. , However, the hydrophobic nature and strong self-stacking of graphene considerably limit the hybridization efficiency of this two-dimensional (2D) material, consequently limiting the possible enhancements in the electron conductivity and electrocatalytic activity of polar MoS 2 species . As an emerging alternative to graphene, monolayered RuO 2 nanosheets with hydrophilic characteristics and negligible self-stacking tendency were considered a viable hybridization substrate to maximize the photocatalytic and electrocatalytic activities of inorganic solids, like CdS and layered double hydroxide, via the enhanced interfacial electronic coupling. , However, the negative charges of both MoS 2 and RuO 2 nanostructures prevent direct hybridization between these materials as a result of the electrostatic repulsion. , This limitation could be addressed by employing metal cations as linkers for both negatively charged species.…”