Hematite (α,-Fe2O3) nanoparticle was synthesized using organometallic compound-ferrocene carboxaldehyde through solventless solid state thermal decomposition technique. The crystal structure, magnetic and morphological properties of the decomposed material were studied using powder X-ray diffraction (XRD), superconducting quantum interference device (SQUID) magnetometry, 57 Fe Mö, ssbauer spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. Structural study confirmed that the synthesized material is hematite with hexagonal phase and good crystallinity. The temperature-dependent magnetization measurement exhibited the Morin transition-the yardstick for hematite formation. Mö, ssbauer spectroscopic study confirmed the purity of phase of the synthesized material. The SEM study observed mostly the agglomerated tiny particles along with some ring-shaped surface structures. The TEM study of the synthesized material showed that the highest distribution of the particles with ~5 nm size. The observed EDX spectra confirmed the existence of Fe and O in the synthesized material. The solid state reaction process leading to hematite on decomposition of ferrocene carboxaldehyde has also been proposed. Present study describes a simple process for the preparation of pure hematite nanoparticle by solventless method.

The effect of Pd nanoparticles geometry has been studied on modifying Fc and Fc-COOH-based electrodes. It has been found to have more reliable results before and after Pd use with Fc-COOH modified electrode. The sensing activity has been performed for ascorbic acid and found quite good results with Fc-COOH-based electrode and surprising results with Pd-modified Fc and Fc-COOH-based electrode, which is further confirmed by performing amperometry titration and observed much high current in case of PdNPs modified Fc-COOH based electrode. The rise in anodic peak current from 14.5A to 33.01A and 1.30A to 3.63 A for Fc and Fc-COOH modified electrodes under a similar environment. The current function continuously rises from 10 to 16A/(mV)0.5 and 6.5 to 13.4A/(mV)0.5. The Rct value decreases from 12.8 k to 1.9 k and 8.3 k to 1.5 krespectively. Electrochemical impedance spectroscopy has also been studied, confirming that PdNPs modified Fc and Fc-COOH-based electrodes having low Rct value, the faster charge transfer is compassionate toward ascorbic acid. Transmission electron microscopy, PXRD, and CV have all been used to characterize the nanomaterial with the following major investigation:(i) The average size of PdNPs1&PdNPs2 is found 18nm & 8nm, (ii) It has been discovered that the palladium content influences both the electrocatalytic effectiveness of novel modified electrode materials and the oxidoreduction electrochemistry of ferrocene and Fc-COOH, and(iii) The modified electrode has an extremely low detection limit for ascorbic acid of < 5 μM

This paper presents the synthesis and the thermal behavior of some symmetrical derivatives containing two ferrocenyl units.The influence of the following factors upon the thermal stability was estimated: the degradation atmosphere, the nature of the linking groups, the number of the benzene units and the flexible segment position.

The eigen values, eigen vector and population analysis of ferrocene and cobaltocene show that the first ten molecular orbitals in ferrocene and first seven in cobaltocene have contribution from 2pz orbitals of carbon of C5H5-and 3d orbitals of iron or cobalt. The extent of involvement of metal orbitals in the two cases are different. In ferrocene the maximum involvement out of 4s and 4p orbital is in the order 4pz > 4py> 4s> 4px and out of 3d orbitals the order of involvement is 3dyz > 3dxz > 3dz2 > 3dx2- y2 > 3dxy. The involvement of corresponding orbital in cobaltocene in respect of 4s and 4p orbitals is in the order 4s> 4pz> 4px and in 3d orbitals the order is 3dyz> 3dxy> 3dxz> 3dz2 > 3dx2-y2. The total involvement in respect of bonding between C5H5-and the metal orbitals as derived from coefficient values is 13.8 in ferrocene and 9.1 in cobaltocene. Comparison of eigen values indicate that ten most stable molecular orbitals have their energies in the range-0.4898 to-0.2314 eV in ferrocene and the seven most stable molecular orbitals in the range-0.4935 to-0.3583 eV in cobaltocene. The energies of first molecular orbital in ferrocene is-1.1084 eV and in cobaltocene-1.1027 eV. The population analysis shows that electrons from 2pz orbitals of carbon and 3d orbitals are provided in molecular orbital in both ferrocene and cobaltocene. The magnitude of contribution in the two cases differs significantly as the sum of the coefficient values of three 4p orbitals and five 3d orbitals in the ferrocene and cobaltocene are 13.8 and 9.1 respectively.