Novel Synthesis of LaFeO₃ Nanostructure Dendrites: A Systematic Investigation of Growth Mechanism, Properties, and Biosensing for Highly Selective Determination of Neurotransmitter Compounds

Single-crystalline novel LaFeO 3 dendritic nanostructures are synthesized by a well-controlled, surfactant-assisted facile hydrothermal process. The morphology of the material is investigated by high-resolution transmission and scanning electron microscopy. The crystal nature and chemical composition of LaFeO 3 dendritic nanostructures are revealed from the X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. Structural characterizations imply the preferential growth along the [121] direction by oriented attachment of LaFeO 3 nanoparticles in the diffusion limit, leading to the formation of LaFeO 3 dendrites. The microscopic studies confirm the formation of dendrites with a length of 3–4 μm, a branch diameter of 80 nm, and a length of 1–1.5 μm. The possible growth mechanism of the dendritic morphology is discussed from the aspect of diffusion and oriented attachment based on experimental results. Further, the electrochemical measurements performed on LaFeO 3 dendritic nanostructures deposited on the surface of a glassy carbon electrode exhibit a strong promoting effect. The oxidation current is proportional to concentration in the linear range of 8.2 × 10 –8 to 1.6 × 10 –7 M with a detection limit of 62 nM at S/N = 3. Meanwhile, the sensor effectively avoids the interference of ascorbic acid and uric acid, and it is successfully applied to determine the dopamine formulations with high selectivity and sensitivity.