A. Diallo

Green synthesis of Co3O4 nanoparticles via Aspalathus linearis: Physical properties

ABSTRACT This study reports on the bio-synthesis and the main physical properties of p-type Co3O4 nanoparticles for the first time by a completely green chemistry process using Aspalathus lineariss natural extract as an effective chelating agent. Their surface/interface and optical properties are reported. In addition to the X-ray diffraction investigations, the Raman, and infrared as well as X-ray photoelectron spectroscopies confirmed the single phase of the Co3O4 nanoparticles. As their average size can be as low as ⟨φparticle⟩ ∼3.6 nm, the reticular atomic plans are under a slight compressive state.

Luminescent Eu2O3 nanocrystals by Aspalathus linearis’ extract: structural and optical properties

Abstract. This contribution reports on the synthesis and the main physical properties of europium oxide nanocrystals synthesized for the first time by a completely green physical–chemistry process using Aspalathus linearis’ leaves natural extract as an effective chelating agent. The structural and optical properties of such biosynthesized nanocrystals were investigated by electron microscopy, selective electron diffraction, energy dispersive spectroscopy, x-rays diffraction, Raman and x-rays photoelectron spectroscopies, as well as room-temperature photoluminescence. The luminescence properties of such cubic nanocrystals with a 16.5 nm average size were characterized by an intense red emission centered at 614.8 nm (D05−F37) with an average time decay of 7.808  μs.

Structural, optical and photocatalytic applications of biosynthesized NiO nanocrystals

ABSTRACT NiO is one of the most important candidates for semiconductors metal oxide nanocrystals by the arrangement of photocatalytic application. However, the photocatalytic performance of biosynthesized nanocrystals using Aspalathus linearis (Burm.f.) R. Dahlgren has not been investigated yet. In this contribution, we synthesize α-Ni(OH)2 using an A. linearis. A heat treatment of the α-Ni(OH)2 is carried out at 300–400°C for 2 h at normal air yields. Furthermore, we have characterized the structural, optical and photocatalytic activity of the samples. The optical results indicate that biosynthesized nanocrystals exhibit UV–visible light absorption and a narrow range distribution of intense green light (518.95 nm) emission, which decreases significantly as annealing temperature increases. The bandgap energies of the sample annealed at 300–400°C shift to lower photon energy, compared to bulk NiO (∼ 4 eV). Moreover, the photocatalytic experimental results reveal that NiO nanocrystals enable color switching of methylene blue. GRAPHICAL ABSTRACT

Nanoscaled Electrocatalytic Optically Modulated ZnO Nanoparticles through Green Process of Punica granatum L. and Their Antibacterial Activities

Most recently, green synthesis of metal oxide nanoparticles has become an interesting subject of the nanoscience and nanotechnology. The use of plant systems has been deemed a green route and a dependable method for nanoparticle biosynthesis, owing to its environmental friendly nature. The present work demonstrates the bioreductive green synthesis of nanosized zinc oxide (ZnO) using peel extracts of pomegranate. Highly crystalline ZnO nanoparticles (ZnO NPs) which are 5 nm in particle size were characterised by HRTEM and XRD. FT-IR spectra confirmed the presence of the biomolecules and formation of plant protein-coated ZnO NPs and also the pure ZnO NPs. Electrochemical investigation revealed the redox properties and the conductivity of the as-prepared ZnO nanoparticles. The optical band gap of ZnO NPs was calculated to be 3.48 eV which indicates that ZnO NPs can be used in metal oxide semiconductor-based devices. Further, the nanomaterials were also found to be good inhibitors of bacterial strains at both low and high concentrations of 5–10 mg mL−1.

Green synthesis of Co 3 O 4 nanoparticles via Aspalathus linearis

ABSTRACT This study reports on the bio-synthesis and the main physical properties of p-type Co3O4 nanoparticles for the first time by a completely green chemistry process using Aspalathus lineariss natural extract as an effective chelating agent. Their surface/interface and optical properties are reported. In addition to the X-ray diffraction investigations, the Raman, and infrared as well as X-ray photoelectron spectroscopies confirmed the single phase of the Co3O4 nanoparticles. As their average size can be as low as ⟨φparticle⟩ ∼3.6 nm, the reticular atomic plans are under a slight compressive state.

Green synthesis of Co3O4nanoparticles viaAspalathus linearis: Physical properties

ABSTRACT This study reports on the bio-synthesis and the main physical properties of p-type Co3O4 nanoparticles for the first time by a completely green chemistry process using Aspalathus lineariss natural extract as an effective chelating agent. Their surface/interface and optical properties are reported. In addition to the X-ray diffraction investigations, the Raman, and infrared as well as X-ray photoelectron spectroscopies confirmed the single phase of the Co3O4 nanoparticles. As their average size can be as low as ⟨φparticle⟩ ∼3.6 nm, the reticular atomic plans are under a slight compressive state.