ZnO nanospheres from LDH nanotubes: article by Prof. Danilo Mustafa's group in ACS Omega

The Department of Materials and Mechanics Physics (DFMT/IFUSP) announces the publication of the article "One-Step Thermal Treatment Route to Obtain ZnO Nanospheres from ZnAlEu LDH Nanotubes" in the journal ACS Omega. The work, signed by Thaina Calaça Futamata, Dimy Nanclares, Alexandre Candido Teixeira, Karina Torre da Fonseca and Prof. Dr. Danilo Mustafa (corresponding author), proposes a novel synthesis route that produces ZnO nanospheres in a single thermal treatment step.

From LDH nanotubes to ZnO nanospheres

The strategy starts from nanotubular ZnAlEu LDH (layered double hydroxide) precursors: controlled calcination promotes the transformation of the nanotubes into ZnO nanospheres, through a restructuring process associated with LDH decomposition and oxide formation. Characterization by XRD, SEM, HRTEM and XRF mapping confirmed the formation of highly crystalline wurtzite ZnO spheres. XRF mapping and XANES analyses further revealed a heterogeneous distribution of europium in the calcined material: Eu-rich domains coexist with regions dominated by the crystalline nanospheres, indicating partial segregation of the element during the thermal transformation — europium remains predominantly in the +3 oxidation state.

Photocatalysis: ~90% dye degradation

The photocatalytic activity of the ZnO-spheres was evaluated through the degradation of Rhodamine 6G (R6G) under UV irradiation: about 90% of the dye was degraded in 300 minutes, following pseudo-first-order kinetics (k_app = 0.601 h⁻¹). The performance is attributed to the spherical morphology — which enhances surface area and light-harvesting efficiency — and to the heterostructure formed between the ZnO spheres and the Eu³⁺-rich domains, which facilitates spatial charge carrier separation at the interface and reduces electron–hole recombination. According to the authors, the work "underscores the potential of LDHs as sacrificial templates for creating morphologically controlled mixed oxide photocatalysts", positioning the ZnO nanospheres as a promising candidate for environmental remediation applications.

Prof. Dr. Danilo Mustafa

Department of Materials and Mechanics Physics (DFMT/IFUSP)

Corresponding author

The article is available at: ACS Omega (2026), 11 (39), 59512–59521. DOI: 10.1021/acsomega.6c05773.

Congratulations to Prof. Danilo Mustafa's group on the new publication!