Band Gap Reduction and Improved Ferromagnetic Ordering via Bound Magnetic Polarons in Zn(Al, Ce)O Nanoparticles. (31st December 2023)

• Record Type: Journal Article
• Authors: Sharma, Ankit; Khangarot, Rama Kanwar; Chattopadhyay, Saikat; Misra, Kamakhya Prakash; Misra, R.D.K.; Babu, P.D.
• Is Part Of: Materials technology. Volume 38:Number 1(2023)
• Publication Date: 2023-12-31
• Subjects: ZnO -- al doping -- ce co-doping -- band gap reduction -- RTFM -- BMPs; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Technological innovations -- Periodicals; 620.1105
• DOI: 10.1080/10667857.2022.2151114
• Languages: English
• ISSNs: 1066-7857

Abstract

ABSTRACT: Polycrystalline nanoparticles of Al-doped and Ce-co-doped ZnO were processed through sol-gel co-precipitation. Crystallite sizes determined from XRD were in the range of 10.90 to 48.77 nm. FTIR spectra indicated a stretching mode of Zn-O bond. The insertion of Al and Ce at Zn-O site created Al-O and Ce-O bonds. UV-vis spectra favoured the formation of impurity levels by doping and co-doping. Their overlapping with the conduction band edge led to the reduction of band-gap. Blue-green emission which arises from radiative recombination of a photogenerated hole with an electron occupying oxygen vacancy was observed in photoluminescence spectra. FESEM suggested granular growth in undoped ZnO which changed to diverse structures such as nano-bar and cluster of elongated grains. Significant improvement in room temperature ferromagnetism (RTFM) was noticed by co-doping of Ce in Al-doped ZnO. Formation of bound magnetic polarons (Ce 3+ -Vo -Ce 3+ ) was the primary mechanism responsible for the improvement in RTFM.