Enhancing Electroconductivity of Yytria-Stabilised Zirconia Ceramic Using Graphene Platlets

Abstract

A simple method to produce graphene-Yytria stabilised zirconia (YSZ) ceramic composite with significant improvement in electrical properties is reported here. The material was consolidated by annealing in presence of Argon gas that allowed densification of the ceramics. A detailed x-ray diffraction (XRD) analysis was used to study the phases and crystallinity of graphene-YSZ ceramic composite. XRD patterns of the sintered composite showed that graphene diffraction peaks were detected at 2θ≈27°. Furthermore, experimental results indicate that electrical conductivity of YSZ composites drastically increased with the addition of graphene platelets, and it reached a value of 2.8 S/cm at 2 wt.%.

Spark Plasma Sintered Zirconia Ceramic Composites with Graphene-Based Nanostructures

“…The thickness (D min ) value for the GNPs in the sintered composite (Z-GNP), higher than the as-received GNPs, may be due to piling up or even agglomeration of the GNPs during the processing and sintering. The results for the composites processed by the different routines indicate that the high-energy planetary ball milling of the GNP/3YTZP powder mixture reduces the average GNP agglomerate size noticeably, in agreement with previously published studies [20,23]. While wet milling achieves a significant reduction (~40%) in the GNP minor diameter (thickness of GNP aggregates) and a~30% decrease in the lateral size (major diameter), dry milling is even more effective, decreasing the particle size with a~70% reduction in the thickness and a drastic (~90%) reduction in the lateral size.…”

“…Similar electrical conductivity values (2800 Sm −1 ) Sm −1 in a direction perpendicular to the SPS axis. Similar electrical conductivity values (2800 Sm −1 ) have been reported in the literature for polymer-derived Si-O-C ceramics synthesized using a gel casting process with the same matrix (YSZ) and 2 wt% FLG [23]. Higher values of electrical conductivity (4000 Sm −1 ) have been reported for 25 vol% GNP in composites with a Si3N4 matrix [27].…”

“…Both increasing GBN content and reducing GBN dimensions increase the electrical conductivity. The major increase in the electrical conductivity with GBN content has already been pointed out by multiple studies in the literature [13,23,27]. However, the increase related to the reduced GBN dimensions obtained in this work can be explained The electrical conductivity exhibits higher values when the current flows perpendicular to the sintering compression axis (σ ⊥ ), with most of the GBNs lying with the ab-plane configuration, as observed for different ceramic matrices and filler contents [8,27].…”

“…Both increasing GBN content and reducing GBN dimensions increase the electrical conductivity. The major increase in the electrical conductivity with GBN content has already been pointed out by multiple studies in the literature [13,23,27]. However, the increase related to the reduced GBN dimensions obtained in this work can be explained by the improvement in the percolation of the GBN network that takes place when the GBN size decreases and their homogeneous distribution in the ceramic grain boundaries improves.…”

Fabrication and preliminary testing of hydroxylammonium nitrate (HAN)-based ceramic microthruster for potential application of nanosatellites in constellation formation flying

“…The YSZ reinforced with 1 wt% graphene platelets shows significant improvement in damping behaviour at low frequency, with improvement of 280% over monolithic YSZ at a frequency of 25 Hz. In our previous study, scanning electron microscopy images revealed that YSZ reinforced with 1 wt% graphene platelets are widely dispersed and distributed uniformly throughout the sample to form a networked structure with electrical conductivity of 0.9 S/cm (Markandan et al 2016). This composition was chosen in the fabrication of electrode of good electrical conductivity and excellent damping behaviour.…”