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MAX phases are a member of ternary carbide and nitride, with a layered crystal structure and a mixed nature of chemical bonds (covalent-ionic-metallic) that promote MAX phases embracing both ceramic and metal characteristics. As a result, MAX phase ceramics emerge with remarkable properties unique from other traditional ceramics. In this review, we focus on alternate processing approaches for MAX phases that are cost-effective and energy-saving. The MAX phase purity, formation of other unwanted phases, microstructure, and properties are influenced by many parameters during processing. Therefore, we highlight the effect of numerous factors, which alternately diminish the efficiency and performance of materials. Here, the impact of several parameters, such as starting materials, stoichiometric composition, temperature, pressure, particle size, porosity, microstructure, mechanical alloying, mechanical activation, ion irradiation, and doping, are summarized to reveal their influence on the synthesis and properties of MAX phases. The potential applications of MAX phases are considered for their development on a commercial scale toward the industry.

A one-step thermo-chemical approach was employed to synthesize ZnFe2O4/rGO nanohybrids with increasing GO concentrations (0, 10, 20, and 30 wt. %). This approach was used to reduce GO while simultaneously synthesizing ZnFe2O4nanoparticles and adhering them to rGO sheets. The nanohybrids were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and impedance analyzer. The XRD patterns confirmed the formation of a face-centered cubic single phase of ZnFe2O4/rGO nanohybrid and SEM images revealed the decoration of ZnFe2O4/rGO nanoparticles on rGO sheets. The dielectric properties improved as GO loadings increased. At 100 Hz, the dielectric constant and dielectric loss increased to 2.04 × 104and 1.20 × 105for ZnFe2O4/rGO nanohybrid with 30 wt. % of GO when compared to pure ZnFe2O4of 4.23 × 102and 1.92 × 103, respectively. The feasibility of this method implies that this nanohybrid can be used for charge storage devices.

Applications of carbon fiber reinforced epoxy-based composites have been highly restricted due to their high cost in the manufacturing process. Cellulose, a cheap and abundant material from nature, shows excellent mechanical property and structural stability. It shows huge potentials in substituting carbon fiber/epoxy with cellulose/epoxy composites to fulfill the great demands for composites with good performance and a reasonable price. This paper first reviews works about the preparation and regulation of cellulose materials based on the very basic concepts of top-down and bottom-up. Then research about the interfacial regulation between cellulose and epoxy has been discussed in two broad classes of covalent and non-covalent modification. Finally, the enhancement effect of cellulose reinforcement has been discussed in two broad classes of dispersive reinforcement and continuous phase reinforcement. The latter can be further divided into three classes according to the dimension feature (1D, 2D, and 3D). The results show that the nanolization of cellulose is necessary for guaranteeing the strength of composites, while the formation of macroscopic and continuous structures can ensure Young’s modulus of composites.