Superior photocatalytic behaviour of novel 1D nanobraid and nanoporous alpha -Fe sub(2)O sub(3) structures

• Published in: RSC advances Vol. 2; no. 21; pp. 8201 - 8208
• Main Authors: Sundaramurthy, J, Kumar, PSuresh, Kalaivani, M, Thavasi, V, Mhaisalkar, S G, Ramakrishna, S
• Format: Journal Article
• Language: English
• Published: 01.08.2012
• Subjects: Ceramics; Dyes; Electrospinning; Nanocomposites; Nanomaterials; Nanostructure; Phase separation; Photocatalysis
• ISSN: 2046-2069
• DOI: 10.1039/c2ra20608k

We have produced novel nanostructures of pure and ceramic alpha -Fe sub(2)O sub(3) using electrospinning, followed by annealing at 500 degree C for 5 h with ramp rate of 5 degree C min super(-1). Electron microscopy clearly reveals the novel morphologies, namely nanobraids and nanoporous alpha -Fe sub(2)O sub(3), suggesting that the precursor, (iron(iii) acetylacetonate, (Fe(acac) sub(3))) to polyvinylpyrrolidone (PVP) ratio greatly influences structural transformations of Fe sub(2)O sub(3). 4 wt% of Fe(acac) sub(3)/PVP solution used for electrospinning at 15 kV a potential produced nanobraid-like ceramic alpha -Fe sub(2)O sub(3), indicating that binodal phase separation is predominant at this ratio. On the other hand, the electrospinning of 6 wt% of Fe(acac) sub(3)/PVP solution induces spinodal phase separation that results in the formation of nanoporous ceramic alpha -Fe sub(2)O sub(3) fibers. The nanobraids and nanoporous ceramic alpha -Fe sub(2)O sub(3) exhibit superior photocatalytic performances of up to 91.2% and 90.2% for the organic dye, Congo red (CR) in the shorter time of 140 min under photoirradiation. It is concluded that the presence of the porous surface and smaller crystallite size in the alpha -Fe sub(2)O sub(3) nanostructures act as active catalytic centers and play a key role in allowing effective interaction between organic dye and alpha -Fe sub(2)O sub(3), in turn enhance photocatalytic degradation performance.