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Single-crystalline novel LaFeO 3 dendritic nanostructures are synthesized by a well-controlled, surfactantassisted 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.

In the present work, perovskite LaFeO 3 thin films with unique morphology were obtained on silicon substrate using radio frequency magnetron sputtering technique. The effect of thickness and temperature on the morphological and structural properties of LaFeO 3 films was systematically studied. The X-ray diffraction pattern explored the highly oriented orthorhombic perovskite phase of the prepared thin films along [121]. Electron micrograph images exposed the network and nanocube surface morphology of LaFeO 3 thin films with average sizes of ∼90 and 70 nm, respectively. The developed LaFeO 3 thin films not only possess unique morphology, but also influence the gas-sensing performance toward NO 2 . Among the two morphologies, nanocubes exhibited high sensitivity, good selectivity, fast response−recovery time, and excellent repeatability for 1 ppm level of NO 2 gas at room temperature. The response time for nanocubes was 24−11 s with a recovery duration of 35−15 s less than the network structure. The sensitivity toward NO 2 detection was found to be in the range 29.60−157.89. The enhancement in gassensing properties is attributed to their porous structure, surface morphology, numerous surface active sites, and the oxygen vacancies. The gas-sensing measurements demonstrate that the LaFeO 3 sensing material is an outstanding candidate for NO 2 detection.

A facile and cost-effective surfactant assisted hydrothermal technique was used to prepare functional floral-like LaFeO 3 nanostructures comprised of nanosheets via a self-assembly process. Scanning electron microscopy images revealed the floral structure of LaFeO 3 comprising of nanosheet petals. The petals of B15 nm thickness and B70-80 nm length observed from transmission electron microscopy self-assembled to form floral structures. X-ray powder diffraction, Fourier-transform infrared spectroscopy and thermal analysis techniques were utilized to determine the structural information and thermal stability. The structural characterization revealed the orthorhombic phase of the prepared LaFeO 3 product with high purity even at a high temperature of 800 1C. The growth mechanism of LaFeO 3 floral nanostructures has been proposed and the band gap energy was estimated to be 2.10 eV using UV-Vis diffuse reflectance spectroscopy.The Brunauer-Emmett-Teller specific surface area was found to be 90.25 m 2 g À1. The visible light photocatalytic activities of LaFeO 3 floral nanostructures exhibited higher photocatalytic efficiency compared to the bulk LaFeO 3 samples for the degradation of rhodamine B (RhB) and methylene blue (MB). The degradation of MB was higher than RhB. The photocatalytic mechanism for the degradation of organic dye has also been proposed.