In this review, we highlight recent advancements in 3D graphene foam synthesis by template-assisted chemical vapor deposition, as well as their potential energy storage and conversion applications. This method offers good control of the number of graphene layers and porosity, as well as continuous connection of the graphene sheets. The review covers all the substrate types, catalysts, and precursors used to synthesize 3D graphene by the CVD method, as well as their most viable energy-related applications.

We unveiled the effect of doping on the morpho-structural and opto/electrical properties of Ca-doped ZnO:Al thin films obtained by RF magnetron sputtering. Scanning electron microscopy (SEM) was performed to reveal the surface morphology, while the composition and crystal structure were investigated by energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The correlation between the microstructure and the electrical conductivity identifies an increase in electrical conductivity up to 145 × 10⁻³ Ω⁻¹·m⁻¹ at 5 wt.% Ca doping level with the decrease in the grain size. Furthermore, the presence of Ca dopant triggers the occurrence of the emission peak at 430 nm and an increase of the green emission peak in PL spectra. Corroborating the electrical measurements with X-ray diffraction and optical measurements, one can infer that the electrical conductivity is dominated by intrinsic defects developed during deposition and by the existence of dopants.

The development of highly efficient sunlight-driven photocatalysts has triggered increased attention due to their merit in effluent treatment through a chemically green approach. To this end, we present herein the synthesis and characterization of the TiO₂/3D-GF/Ni hybrid emphasizing the main structural and morphological properties and the photodegradation process of a highly resistant aromatic azo dye, methyl orange, under both UV light and simulated sunlight. Three-dimensional (3D) graphene was grown by the thermal CVD method on the nickel foam and subsequently coated with thin films of anatase employing the sol–gel method. Thereafter, it was gratifyingly demonstrated that the hybrid nanomaterial, TiO₂/3D-GF-Ni, was able to bring about more than 90% decolorization of methyl orange dye after 30 min under simulated sunlight irradiance. Moreover, the efficiency of the methyl orange decolorization was 99.5% after three successive cycles. This high-performance photocatalyst which can effectively decolorize methyl orange will most likely make a great contribution to reducing environmental pollution by employing renewable solar energy.

Copper-doped zinc oxide thinfilms, (1, 3,5 at. %) have been synthesized via sol-gel spin coating technique. Main objectives of the reported -work are to investigate the effect of copper doping on morphology, compositional, structure and on opto-electrical properties of ZnO thin films. To achieve the mentioned objectives, Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDX), X- Ray Diffraction (XRD), UV-vis techniques and the current-voltage (I-V) measurements -were performed. SEM result show a porous morphology. The % Cu concentration, determined by EDX analysis, are 0.66%, 3.73% and 6.26% in good agreement with the Cu theoretical concentration. XRD analysis shows that the films are nanocrystalline zinc oxide with the wurtzite structure. From optical measurements, a significant decrease in average optical transmission from 93 to 76 % is observed for all doped samples and the band gap value decreased from 3.20 to 3.00 eV which are related to the presence of defects due to Cu incorporation. The resistivity value of 9.64Ω10 ^-4 Ω-cm have been achieved -which is very promising in electronics for field effect transistors.