Multifunctional BiFeO3 nanostructure anchored TiO2 nanotubes are fabricated by coupling wet chemical and electrochemical routes. BiFeO3/TiO2 nano-heterostructure exhibits white-light-induced ferroelectricity at room temperature. Studies reveal that the photogenerated electrons trapped at the domain/grain boundaries tune the ferroelectric polarization in BiFeO3 nanostructures. The photon controlled saturation and remnant polarization opens up the possibility to design ferroelectric devices based on BiFeO3. The nano-heterostructure also exhibits substantial photovoltaic effect and rectifying characteristics. Photovoltaic property is found to be correlated with the ferroelectric polarization. Furthermore, the nonvolatile resistive switching in BiFeO3/TiO2 nano-heterostructure has been studied, which demonstrates that the observed resistive switching is most likely caused by the electric-field-induced carrier injection/migration and trapping/detrapping process at the hetero-interfaces. Therefore, BiFeO3/TiO2 nano-heterostructure coupled with logic, photovoltaics and memory characteristics holds promises for long-term technological applications in nanoelectronics devices. © 2016 AIP Publishing LLC.

A SARKAR

G G KHAN

A CHAUDHURI

A DAS

K MANDAL

Fulltext

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

&nbsp;

The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

&nbsp;

It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Multifunctional BiFeO3/TiO2 nano-heterostructure: Photo-ferroelectricity, rectifying transport, and nonvolatile resistive switching property

Applied Physics Letters

Nanoscale

The formation and detection techniques of oxygen vacancies in titanium oxide-based nanostructures

Materials Today: Proceedings

Synthesis of BiFeO3 nanoparticle anchored TiO2-BiFeO3 nano-heterostructure and exploring its different electrochemical aspects as electrode

The poor visible light absorption, defect-mediated charge carrier recombination, slow water oxidation kinetics, and charge transportation limit the performance of TiO2 photoelectrodes for water oxidation. In order to tackle these issues, here a one-dimensional photoanode is designed by electrodepositing a p-ZnCo2O4 nanolayer on n-TiO2 nanotubes surface and finally electrochemically coupling the TiO2/ZnCo2O4 surface with an ultrathin layer of the cobalt phosphate (Co-Pi) catalyst nanoparticles. These typical TiO2/ZnCo2O4@Co-Pi nanoheterostructures exhibit a remarkably enhanced visible light driven photoelectrochemical property with applied bias photoconversion efficiency (ABPE) ∼ 3% at 0.2 V vs NHE. The TiO2/ZnCo2O4@Co-Pi nanoheterostructures also show enhanced visible light absorption with large photocurrent density ∼440% higher than that of the TiO2 nanotubes electrode at 1.2 V vs Ag/AgCl and significantly low onset potential for water oxidation. Studies on the transient photocurrent and flat-band potential demonstrate the remarkable improvement in the photogenerated charge carrier separation or reduced recombination because of the favorable band alignment at the heterointerface. The Co-Pi catalyst further boosts the water oxidation reaction by reducing electron-hole pair recombination through the suppression of the surface trap states. Moreover, Co-Pi also serves as a hole-acceptor layer, improving the charge-transfer kinetics for an enhanced photoelectrochemical performance. © 2017 American Chemical Society.

Journal of Physical Chemistry C

Designing Co-Pi Modified One-Dimensional n-p TiO2/ZnCo2O4 Nanoheterostructure Photoanode with Reduced Electron-Hole Pair Recombination and Excellent Photoconversion Efficiency (&gt;3%)

This article demonstrates comprehensive studies on different visible-light driven photoelectrochemical and photocatalytic aspects of a hydrothermally synthesized n-type H2Ti3O7 (HTO) nanowire mesh and its carbon and nitrogen functionalized counterparts, namely C-HTO and N-HTO. It was found that the presence of various defect states within the band gap of HTO, C-HTO and N-HTO nanowires, make them photoactive under visible-light. The photo-conversion efficiencies of HTO, C-HTO, and N-HTO nanowire electrodes are about 0.066, 0.129, and 0.076%, respectively, at around 1 V vs. Ag/AgCl. Carbon functionalization of HTO nanowires has been found to be most beneficial in increasing the charge carrier density, resulting in the highest current density, high photo conversion efficiency, remarkable photoelectrochemical water splitting performance and enhanced photocatalytic activity. The photocurrent density of the C-HTO NWs was found to be 0.0562 mA cm-2 at 1 V vs. Ag/AgCl, which is almost two times that of the pristine HTO NWs (0.029 mA cm-2). Although nitrogen functionalization increases the charge carrier density of the HTO nanowires, nitrogen incorporation produces lots of recombination centres in the nanowires, which are found to play a detrimental role in the photoelectrochemical and photocatalytic performance of N-HTO nanowires, limiting the expected performance. Therefore, the present study demonstrates a suitable surface engineering technique for nanostructures to maximize the utilization of green solar light. © 2016 the Owner Societies.

Physical Chemistry Chemical Physics

Surface functionalized H2Ti3O7 nanowires engineered for visible-light photoswitching, electrochemical water splitting, and photocatalysis

Here, we report the synthesis of TiO2/BiFeO3 nanoheterostructure (NH) arrays by anchoring BiFeO3 (BFO) nanoparticles on TiO2 nanotube surface and investigate their pseudocapacitive and photoelectrochemical properties considering their applications in green energy fields. The unique TiO2/BFO NHs have been demonstrated both as energy conversion and storage materials. The capacitive behavior of the NHs has been found to be significantly higher than that of the pristine TiO2 NTs, which is mainly due to the anchoring of redox active BFO nanoparticles. A specific capacitance of about 440 F g-1 has been achieved for this NHs at a current density of 1.1 A g-1 with ∼80% capacity retention at a current density of 2.5 A g-1. The NHs also exhibit high energy and power performance (energy density of 46.5 Wh kg-1 and power density of 1.2 kW kg-1 at a current density of 2.5 A g-1) with moderate cycling stability (92% capacity retention after 1200 cycles). Photoelectrochemical investigation reveals that the photocurrent density of the NHs is almost 480% higher than the corresponding dark current and it shows significantly improved photoswitching performance as compared to pure TiO2 nanotubes, which has been demonstrated based the interfacial type-II band alignment between TiO2 and BFO. (Graph Presented). © 2015 American Chemical Society.

ACS Sustainable Chemistry and Engineering

Three-Dimensional Nanoarchitecture of BiFeO3 Anchored TiO2 Nanotube Arrays for Electrochemical Energy Storage and Solar Energy Conversion

RSC Advances

TiO2/ZnO core/shell nano-heterostructure arrays as photo-electrodes with enhanced visible light photoelectrochemical performance

Nature Communications

Ferroelectric domain wall motion induced by polarized light

The Journal of Physical Chemistry C

White-Light-Controlled Magnetic and Ferroelectric Properties in Multiferroic BiFeO3 Square Nanosheets

Journal	Data powered by TypesetApplied Physics Letters
Publisher	Data powered by TypesetAmerican Institute of Physics Inc.
ISSN	0003-6951