1 Introduction

Recently, multiferroic materials that exhibit multiple ferroic orders simultaneously have gained widespread applications in spintronics, information storage, sensors, actuators, and photovoltaic devices [1,2,3,4]. Amongst the several multiferroic materials, BiFeO3 (BFO) is probably the only lead-free multiferroic material showing room temperature ferroelectric and G-type anti-ferromagnetic orders simultaneously. Rhombohedrally distorted perovskite (ABO3) structured BFO, with R3c space group shows high anti-ferromagnetic Neel temperature, (TN ~ 370 °C) and high ferroelectric temperature (TC ~ 830 °C) [5, 6]. The anti-ferromagnetic nature in BFO arises due to partially filled d-orbitals of Fe3+ at B site, and ferroelectric order develops due to the presence of 6s2 lone pair of electrons of Bi3+at A site [7]. Owing to its unique features such as large remnant polarization (90µC/cm2) and relatively lower bandgap (2.08−2.7 eV) compared to other oxide-based ferroelectrics, BFO is considered as one of the emerging ferroelectric photovoltaic materials [4].

Additionally, this material shows above bandgap photovoltage and bulk based photovoltaic effect due to the polarization-based charge transport mechanism. Therefore there is a possibility to implement this advantage to higher photovoltaic efficiency if the short circuit current density can also be augmented. Despite these intriguing physical properties, BFO suffers from some significant limitations like large leakage current density and complex phase formation due to the volatile nature of bismuth. These factors restrict its applicability to device fabrication. Meanwhile, several attempts have been made to overcome these obstacles which include do** at Bi-site with rare-earth ions (Y, Pr, Ho, Eu, Gd, Sm, etc.) [8,9,10,11,12,13] and do** at Fe-site with transition metal ions (Co, Cr, Mn, Ni, etc.) [14, 15]. Do** at A site with rare-earth elements controls bismuth volatility and hence suppresses the generation of oxygen vacancies while do** at B site with donor elements fills the oxygen vacancies, and therefore reduces the leakage current.

Furthermore, most of these attempts have proved beneficial in modifying various other parameters, such as dielectric constant, resistivity, magneto-electric coupling, and optical bandgap values. Mn-substitution at Fe site in BFO is attractive, owing to its excellent chemical stability (in terms of oxidation state), comparable size, and its tendency to modify optical bandgap. Zhu et al. tailored the optical band gap of BFO with co-do** of Eu and Mn atoms in BFO from 2.40−1.49 eV [16]. Chandel et al. reported enhanced electrical and magnetic properties in Mn-doped BFO nanoparticles [22]. Hiroshi et al. investigated the impact of annealing temperature on Mn-doped BFO films [6]. The effect of Mn-do** concentration on the multiferroicity of BFO was investigated by Chauhan et al. [5]. Irfan et al. tailored the optical bandgap of BFO from 2.08−1.45 eV via chemical substitution of Sm and Mn at Bi and Fe sites of BFO [13]. So far, no investigations exist to understand the influence of annealing time and annealing temperature on the optical properties of BFO.

Synthesis of pure phase BFO is a challenging task because of the volatile nature of bismuth, and the kinetics of formation. Various methods have been adopted so far, to prepare pure phase BFO, which include solid-state reaction method [17], liquid phase sintering [18], citrate precursor method [19, 22], the hydrothermal method [20], and sol–gel method [14]. Most of these methods require high annealing temperature (usually more than 650 °C), thus yielding one or the other undesirable secondary phases along with pure phase BFO due to the volatile nature of bismuth. Several research groups have used an excessive amount of Bi (between 3−10 mol%) to prevent undesirable effects arising from the volatility of Bi [11, 21]. At the same time, some others are doing post-annealing nitric acid treatment to purify the samples [17]. Thus, the impact of thermal annealing treatment (annealing temperature and annealing time) on the synthesis of BFO appears to be a suitable method to reduce/eliminate the occurrence of secondary phases in BFO. Furthermore, among the several synthesis routes mentioned above, the citrate precursor method seems to be one of the potential alternatives for synthesizing nanoparticles, as this allows reasonable control of the stoichiometry. Moreover, this method is carried out at a relatively low temperature (600 °C) and also a cost-effective process with simple processing steps. The steps involved in this process are mixing, gelation, drying, and sintering, and hence this method does not require complicated or expensive instrumentation.

As far as our knowledge is concerned, several research groups have synthesized single-phase BFO by adopting advanced techniques or by post leaching treatment. However, by adopting the citrate precursor method, it is very difficult to obtain a pure/primary-phase of undoped and Mn-doped BFO nanoparticles at low temperatures (550 °C). Most of the reported methods have (1) lead to the formation of secondary phases, (2) used excessive bismuth content, or (3) adopted post-annealing nitric acid treatment for purification. Therefore, in this study, we report the phase formation of undoped BFO and Mn-doped BFO (with a negligible trace of impurity phase) using citrate precursor method at lower temperature (550 °C) by optimizing annealing temperature and annealing time. After that, we systematically varied annealing temperature (from 500 °C to 600 °C) and annealing time (from 2−6 h) of different series of samples and carefully investigated their effects on structural, morphological, and optical properties. The results showed a significant variation in the optical bandgap of Mn-doped BFO with annealing temperature and annealing time. The optical bandgap of BFO was reduced to 1.62 eV by tuning Mn-do**, annealing temperature, and annealing time.

2 Experimental details

2.1 Preparation

In the current study, single-phase undoped BFO, and Mn-doped nanoparticles were prepared by adopting the citrate precursor method. The precursors taken in the synthesis process were bismuth nitrate pentahydrate (Bi(NO3)3.5H2O), iron nitrate nonahydrate (Fe(NO3)3.9H2O), manganese acetate dihydrate (C6H9MnO6.2H2O), citric acid (C6H8O7), and diluted nitric acid (HNO3). All the reagents were purchased from Sisco Research Laboratories (SRL) Pvt. Ltd. India and were used without further purifications owing to their high purity analytical grades. In the first step, stoichiometric proportions of bismuth nitrate pentahydrate, iron nitrate nonahydrate, and manganese acetate were dissolved in the distilled water solvent at room temperature. Citric acid, which is a chelating agent, was added to the metal nitrate solution with citric acid to metal cation molar ratio of 2:1. Secondly, diluted nitric acid was added drop-wise to the light-yellow coloured mixture at constant stirring until a homogeneous sol was obtained. The resultant precursor sol was heated at 80 °C under vigorous stirring using a magnetic stirrer to procure gel-deposit. Immediately after the gelation process, the gel-deposit was dried at 130 °C for about 6 h to get a fluffy residue. Finally, the flocculent residue was ground using the pestle and mortar to extract fine powder. The as-obtained fine powder was calcined under controlled thermal treatments ranging from 350−450 °C to optimize the calcination temperature, which was later found to be 400 °C. Subsequently, the calcined powder (at 400 °C) was ground again and pelletized into cylindrically shaped pellets with a 10 mm diameter of varying thickness. In the end, the obtained pellets were annealed at different temperatures (500 °C, 550 °C, and 600 °C) for different durations (2 , 4 , and 6 h) to optimize the single-phase formation of undoped and Mn-doped BFO. The heating rate (4 °C/minute) was maintained constant at all the stages of this process. Undoped BFO was prepared using the same procedure without adding manganese acetate dehydrates. The flow chart describing the present synthesis method is depicted in Fig. 1.

Fig. 1
figure 1

Synthesis procedure

Full size image

2.2 Characterization

X-ray diffraction (XRD) studies were carried out to determine the crystal structure of the prepared compounds using X-ray diffractometer (Rigaku Ultima-IV XRD) with CuKα (λ = 1.5406 Å) radiation source with step size 0.02° in the 2θ range from 20°−70°. Field emission scanning electron microscope (FEI- Apero LoVac FESEM) (accelerating voltage 20 kV) assembled with energy-dispersive X-ray spectroscopy (EDAX) was used to investigate the morphological and compositional features of all the samples. Fourier transform infrared (JASCO FT/IR-4200) spectral studies were carried out to investigate the stretching and bending behaviour of distinct bonds existent in the samples. Optical absorption spectral analysis of the samples was carried out using a UV–vis spectrophotometer (JASCO V—670), and the bandgap was calculated using Tauc’s relation.

3 Results and discussions

3.1 Structural properties

3.1.1 Effect of annealing temperature on BFO

The phase formation and crystal structures of all the samples, annealed at different temperatures, and times were determined by XRD studies. Figure 2a shows the XRD patterns of undoped BFO nanoceramics calcined at different temperatures (350 °C, 400 °C, and 450 °C). The XRD patterns of the samples calcined at lower temperatures (350 °C, 400 °C, and 450 °C) showed only a few Bragg peaks depicting the weak crystalline nature along with some secondary phases. To enhance the crystalline quality of the prepared samples, these were annealed at higher temperatures. Figure 2bdepicts the XRD patterns of the undoped BFO samples calcined at 400 °C and annealed at 500 °C, 550 °C, and 600 °C. The XRD peaks of these samples reveal that both the crystallinity and phase purity of samples improved significantly with increasing annealing temperature. Furthermore, the XRD pattern of the sample annealed at 550 °C confirmed the phase formation of BFO with a negligible trace of impurity phase having rhombohedrally distorted perovskite structure, and R3c space group [21]. These results are in agreement with the JCPDS data file (PDF#861,518). However, the samples annealed at 500 °C and 600 °C showed few secondary peaks of Bi2Fe4O9 in the XRD pattern, which might be due to kinetics of formation, and volatile nature of bismuth [21].

Fig. 2
figure 2

XRD pattern of a BFO calcined at (I) 350 °C, (II) 400 °C, (III) 450 °C, b BFO calcined at 400 °C and annealed at (I) 500 °C, (II) 550 °C, (III) 600 °C

Full size image

3.1.2 3.1.2 Effect of Mn-do** on BFO

Figure 3a shows the XRD patterns of BiFe1-xMnxO3 (x = 0.0, 0.03, 0.05) (BFMO) calcined at 400 °C for 2 h and annealed at 550 °C for 2 h. All the Bragg’s peaks confirmed the formation of a single-phase of Mn-doped BFO. However, a minute trace of the secondary phase (Bi2Fe4O9) was also detected, which was found to decrease with an increase in Mn-concentration. However, for 5 mol% Mn-doped sample, the Bi2Fe4O9 disappeared completely, and a new impurity phase of Bi36Fe2O57 appeared in the XRD pattern, as shown in Fig. 3a. As seen in Fig. 3a, the (110) and (104) planes start merging into a single peak with Mn-do** and finally appears as a single peak at 5 mol% do** concentration. The merging of twin peaks suggests lattice distortion owing to the difference in ionic radii of the dopant and host ions, which results

Fig. 3
figure 3

a XRD pattern of BiFe1-xMnxO3 compositions calcined at 400 °C and annealed at 550 °C with (I) x = 0.00, (II) x = 0.03, (III) x = 0.05 b Magnified view of BiFe1-xMnxO3

Full size image

in structural distortion with Mn-substitution [21, 22]. Moreover, the magnified view of the XRD patterns (Fig. 3b) clearly shows the overlap** of the peaks and the shifting of peaks towards higher 2θ values with Mn-do** which can be ascribed to size difference in the ionic radii of Fe2+ (0.782 Å) and Mn3+ (0.645 Å) ions. The obtained results were found to be in line with the studies carried out by Chandel et al.[22] and Hua et al. [23]. Therefore, one can notice that Mn-substitution in Fe site is an effective way to modulate the crystal structure of BFO. Thus, 3 mol% Mn-do** in BFO is considered to be the optimum do** concentration for tailoring the optical parameters.

3.1.3 Effect of Annealing Temperature on Mn-doped BFO

Next, to investigate the effect of annealing temperature on Mn-doped BFO, these samples were annealed at different temperatures. Figure 4 depicts the XRD patterns of BFMO (3 mol %) samples annealed at different temperatures (500 °C, 550 °C, and 600 °C) for 2 h. It is evident from these XRD patterns that all the BFMO samples annealed at different temperatures exhibit a rhombohedrally distorted perovskite structure. Moreover, the intensity of impurity peaks of these samples first reduced with increasing annealing temperature from 500 °C to 550 °C. Subsequently, the impurity peaks increased for the sample annealed at 600 °C. These results suggest that annealing temperature plays a decisive role in the pure phase formation of BFMO nanoparticles. Hence, annealing at 550 °C was found to exhibit the phase formation of BFO with a negligible trace of impurity phase and better crystallinity as compared to other BFMO samples annealed at different temperatures.

Fig. 4
figure 4

XRD pattern of BFMO calcined at 400 °C and annealed at (I) 500 °C, (II) 550 °C, (III) 600 °C

Full size image

3.2 Effect of Annealing Time on Mn-doped BFO

Furthermore, to investigate the efficacy of annealing time on Mn-doped samples, the samples were annealed at 550 °C for different durations. Figure 5 shows the XRD patterns of these BFMO (3 mol %) samples annealed at 550 °C for 2 h, 4 h, and 6 h. All the samples exhibited good crystallinity, indicating the formation of perovskite structured material. However, the secondary phase formation was found to increase with increasing annealing time, which could be accounted for the excessive number of oxygen vacancies at higher dwell times or the creation of bismuth vacancies due to the volatile nature of bismuth. In addition to this, the peak widths at half maxima were found to decrease with an increase in annealing temperature, indicating variation in particle size. Thus, annealing temperature and time provide another tool to modulate the particle size, which in turn alters the physical properties.

Fig. 5
figure 5

XRD pattern of BFMO calcined at 400 °C and annealed at 550 °C for (I) 2 h, (II) 4 h, (III) 6 h

Full size image

Moreover, to correlate crystallite size with Mn-do**, annealing time, and annealing temperature, the average crystallite size was assessed from peak widths at half maximum of all the samples, using Debye–Scherrer formula

$$D = \frac{k\lambda }{{\beta {{\cos\theta }}}}$$

where D is crystallite size, k is the shape factor (~ 0.9), β is full width at half maxima (radians), λ is the wavelength of Cu Kα, and θ is diffraction angle. It was found that the average crystallite size decreased from 44−17 nm with increasing Mn concentration owing to the smaller ionic radius of Mn3+ (0.0645 Å) ion compared to the host site, Fe2+ (0.782 Å) ion. This result validates the substitution of Mn in the Fe site inside the host matrix. In addition to this, the average particle size was found to increase with an increase in annealing temperature and annealing time for both undoped as well as Mn-doped samples. The average crystallite sizes of all the samples are summarized in Table 1.

3.3 Morphological properties

Figure 6a,b shows the micrographs of BFO and BFMO samples annealed at 550 °C for 2 h. As evident from these micrographs, the microstructures are evolving into more (or) less uniform granular structures with negligible porosity, and also, a gradual reduction in granular size with Mn do** is detectable. This result is in good agreement with XRD studies. Furthermore, the results showed a continuous grain growth in the BFO sample, whereas Mn-doped samples seem to experience discontinuous grain growth in some regions. The above analysis revealed that Mn do** inhibits grain growth, which might be due to different diffusion rates of metal ions.

Fig. 6
figure 6

a FESEM micrograph of BFO calcined at 400 °C and annealed at 550 °C for 2 h b FESEM micrograph of BFMO calcined at 400 °C and annealed at 550 °C for 2 h

Full size image

Figure 7a−c show the FESEM images of BFMO samples annealed at different temperatures (500 °C, 550 °C, 600 °C) respectively. The specimen consists of small clusters of particles at lower annealing temperatures. As the annealing temperature was increased, the grain size was found to increase. Fig 7d−f depict the SEM images of BFMO samples annealed at 550 °C for different time durations (2 h, 4 h, and 6 h), respectively. It appears from these micrographs that granular size increases upon increasing annealing time and the samples become more agglomerated for higher annealing times.

Fig. 7
figure 7

FESEM micrograph of BFMO annealed at a 500 °C/2 h, b 550 °C/2 h, c 600 °C/2 h, d 550 °C/2 h, e 550 °C/4 h, f 550 °C/6 h

Full size image

3.4 Compositional properties

Energy-dispersive X-ray spectral studies were carried out to check the chemical composition of both the undoped BFO and BFMO samples, and the recorded spectra are shown in Fig. 8a and Fig. 8b, respectively. The analysis of these spectral patterns confirmed the presence of Mn in the doped sample, and also ruled out the presence of foreign elements in all the samples. In addition to this, the results obtained also gave a quantitative composition of all the constituents. The elemental concentration in terms of the atomic percentage of bismuth, iron, and oxygen in the undoped sample was found to be 20.34%, 22.73%, and 56.93%, respectively. In BFMO, the percentages of bismuth, iron, manganese, and oxygen are 20.29%, 19.67%, 2.36%, and 57.68%, respectively.

Fig. 8
figure 8

EDAX spectra of a BFO, b BFMO, Elemental map** images of constituent elements in BFMO c Bi, d Fe, e Mn, f O, g all constituents mixed

Full size image

3.5 Elemental map** studies

To confirm the uniformity of dopant (Mn) across the regions in the sample, elemental map** images were recorded for the BFMO sample. Figure 8c−g show the images obtained from elemental map** studies. Figure 8c, d, e show a uniform notation in the colour codes of Bi, Fe, and Mn, respectively, which indicates the homogeneous distribution of the elements in the BFO matrix. However, a non-uniform spread of the colour in Fig. 8f shows an irregular variation of oxygen content in the BFO matrix. The dark patches in Fig. 8f indicates the oxygen vacant regions. The mixed map** image of all the constituent elements is shown in Fig. 8g. Thus, the elemental map** analysis confirms the homogeneous distribution of the dopant ions in the BFO matrix. These results suggest that the citrate precursor preparation technique facilitates the uniform distribution of dopants in the BFO matrix.

3.6 3.5 FTIR studies

Figure 9 shows the FTIR spectra of undoped BFO and BFMO samples recorded in the wavenumber range 450−2000 cm−1. FTIR spectral analysis is a crucial characterization tool that gives the qualitative as well as quantitative information about the sample by identifying the chemical bonds present in the sample. The sharp peaks in the band range 450−600 cm−1 are attributed to Fe–O stretching vibration and O–Fe–O bending vibration of the octahedral FeO6 group. This result confirms the perovskite structure of our samples and is consistent, as reported by Liu et al. [24]. The peak at 1636 cm−1 is due to the bending vibration of O–H−O present in the sample, which might have incorporated during the synthesis process [8]. The bands observed around 1400 cm−1 and 1150 cm−1 are attributed to the trapped nitrates in the xerogel matrix during the synthesis process [8, 24]. Moreover, in the present work, it was observed that the strong absorption band (metal–oxygen band) shifted towards higher wavenumber with Mn-do**, which might be attributed to distortion occurring in the bonds due to difference in ionic radii. The positions of all obtained absorption bands are given in Table 2.

Fig. 9
figure 9

FTIR spectra of a BFO, b BFMO

Full size image
Table 1 Average crystallite size of undoped and Mn-doped samples under different conditions of thermal treatment
Full size table
Table 2 Absorption bands of BFO and BFMO samples
Full size table

3.7 Optical properties

In order to study the optical properties of undoped BFO and BFMO samples under different thermal annealing conditions, the absorption spectra of all the samples were recorded in the wavelength range of 350−750 nm using a UV–visible photo-spectrometer. Figure 10a shows the strong absorption of undoped and Mn-doped samples in the visible region. A significant increase in absorbance was noticed with Mn-do**. Mn-substitution seems to be effectively absorbing more light in the wavelength range 500−750 nm. Absorption of light in the longer wavelength signifies narrowing energy absorption edge, which suggests a reduction in optical bandgap.

Fig. 10
figure 10

Absorbance spectra of a BiFe1-xMnxO3 compositions b BFMO annealed at different temperatures for 2 h, c BFMO annealed at 550 °C for different durations

Full size image

To quantify this fact, the absorption coefficient (α) of undoped and Mn-doped samples was calculated at 375 nm. The absorption coefficient was found to increase by 31% in comparison to BFO. These results predict that Mn-substitution in BFO may augment the light-harvesting efficiency (LHE) of the BFO matrix. The absorption coefficient was calculated using the relation

$$\alpha = 2.303\frac{{\left( {{\text{Ab}}} \right)}}{t}$$

where α is the absorption coefficient, (Ab) is absorbance, and t is the thickness of the sample [26]. To describe the relation between optical bandgap, and thermal treatment conditions of BFMO samples, the absorption spectra of all the samples with different annealing temperatures, and various heat dwell times were recorded and are shown in Figs. 10b,c, respectively.

The optical bandgap values of all the samples are calculated using Tauc’s relation as given below [26,

References

  1. Casper MD, Losego MD, Maria JP (2013) Optimizing phase and microstructure of chemical solution-deposited bismuth ferrite (BiFeO3) thin films to reduce DC leakage. J Mater Sci 48(4):1578–1584. https://doi.org/10.1007/s10853-012-6914-0

    Article  Google Scholar 

  2. Ramesh R, Spaldin NA (2007) Multiferroics: progress and prospects in thin films. Nat Mater 6(1):21–29. https://doi.org/10.1038/nmat1805

    Article  Google Scholar 

  3. Roy A, Gupta R, Garg A (2012) Multiferroic memories. Adv Condens Matter Phys. https://doi.org/10.1155/2012/926290

    Article  Google Scholar 

  4. Irfan S, Zhuanghao Z, Li F, Chen YX, Liang GX, Luo JT, ** F (2019) Critical review: Bismuth ferrite as an emerging visible light active nanostructured photocatalyst. J Mater Res Technol. https://doi.org/10.1016/j.jmrt.2019.10.004

    Article  Google Scholar 

  5. Chauhan S, Kumar M, Chhoker S, Katyal SC, Singh H, Jewariya M, Yadav KL (2012) Multiferroic, magneto-electric and optical properties of Mn doped BiFeO3 nanoparticles. Solid State Commun 152(6):525–529. https://doi.org/10.1016/j.ssc.2011.12.037

    Article  Google Scholar 

  6. Naganuma H, Miura J, Okamura S (2009) Annealing temperature effect on ferroelectric and magnetic properties in Mn-added polycrystalline BiFeO 3 films. J Electroceram 22(1–3):203–208. https://doi.org/10.1007/s10832-007-9400-3

    Article  Google Scholar 

  7. Seshadri R, Hill NA (2001) Visualizing the role of Bi 6s “lone pairs” in the off-center distortion in ferromagnetic BiMnO3. Chem Mater 13(9):2892–2899. https://doi.org/10.1021/cm010090m

    Article  Google Scholar 

  8. Mukherjee A, Hossain SM, Pal M, Basu S (2012) Effect of Y-do** on optical properties of multiferroics BiFeO3 nanoparticles. Appl Nanosci 2(3):305–310. https://doi.org/10.1007/s13204-012-0114-8

    Article  Google Scholar 

  9. Khomchenko VA, Troyanchuk IO, Kovetskaya MI, Kopcewicz M, Paixão JA (2012) Effect of Mn substitution on crystal structure and magnetic properties of Bi1−xPrxFeO3 multiferroics. J Phys D 45(4):045302. https://doi.org/10.1088/0022-3727/45/4/045302

    Article  Google Scholar 

  10. Wu YJ, Zhang J, Chen XK, Chen XJ (2011) Phase evolution and magnetic property of Bi1−xHoxFeO3 powders. Solid State Commun 151(24):1936–1940. https://doi.org/10.1016/j.ssc.2011.09.020

    Article  Google Scholar 

  11. HY Dai HZ Liu JF Du T Li RZ Xue ZP Chen 2014 Effect of Sintering Temperature on the Microstructure, Electrical, and Magnetic Properties of Bi0.85Eu0.15FeO3 Ceramics J Supercond Nov Magn 27 9 2105 2110 https://doi.org/10.1007/s10948-014-2558-4s

  12. Kumar A, Varshney D (2012) Crystal structure refinement of Bi1− xNdxFeO3 multiferroic by the Rietveld method. Ceram Int 38(5):3935–3942. https://doi.org/10.1016/j.ceramint2012046

    Article  Google Scholar 

  13. Irfan S, Shen Y, Rizwan S, Wang HC, Khan SB, Nan CW (2017) Band-gap engineering and enhanced photocatalytic activity of Sm and Mn doped BiFeO3 nanoparticles. J Am Ceram Soc 100(1):31–40. https://doi.org/10.1111/jace.14487

    Article  Google Scholar 

  14. WA Wani S Kundu K Ramaswamy H Venkataraman 2020 Structural, morphological, optical and dielectric investigations in cobalt doped bismuth ferrite nanoceramics prepared using the sol-gel citrate precursor method J Alloys Compd 156334 https://doi.org/10.1016/j.jallcom.2020.156334

  15. Naganuma H, Miura J, Okamura S (2008) Ferroelectric, electrical and magnetic properties of Cr, Mn Co, Ni, Cu added polycrystalline BiFeO3 films. Appl Phys Lett 93(5):052901. https://doi.org/10.1063/1.2965799

    Article  Google Scholar 

  16. Zhu Y, Quan C, Ma Y, Wang Q, Mao W, Wang X, Huang W (2017) Effect of Eu, Mn co-do** on structural, optical and magnetic properties of BiFeO3 nanoparticles. Mater Sci Semicond Process 57:178–184. https://doi.org/10.1016/j.mssp.2016.10.023

    Article  Google Scholar 

  17. Bernardo MS, Jardiel T, Peiteado M, Caballero AC, Villegas M (2011) Reaction pathways in the solid state synthesis of multiferroic BiFeO3. J Eur Ceram Soc 31(16):3047–3053

    Article  Google Scholar 

  18. Sagdeo A, Mondal P, Upadhyay A, Sinha AK, Srivastava AK, Gupta SM, Chowdhury P, Ganguli T, Deb SK (2013) Correlation of microstructural and physical properties in bulk BiFeO3 prepared by rapid liquid-phase sintering. Solid State Sci 18:1–9. https://doi.org/10.1016/j.solidstatesciences.2012.12.017

    Article  Google Scholar 

  19. Wani, W. A., Ramaswamy, K., Venkataraman, B. H., & Kundu, S. (2019, July). Influence of Transition Metal Ion Do** on Structural and Dielectric Properties of Sol-gel Synthesized Bismuth Ferrite Nanoceramics. In 2019 IEEE International Symposium on Applications of Ferroelectrics (ISAF) (pp. 1–3). IEEE. https://doi.org/https://doi.org/10.1109/ISAF43169.2019.9034952

  20. Yang X, Zhang Y, Xu G, Wei X, Ren Z, Shen G, Han G (2013) Phase and morphology evolution of bismuth ferrites via hydrothermal reaction route. Mater Res Bull 48(4):1694–1699. https://doi.org/10.1016/j.materresbull.2013.01.032

    Article  Google Scholar 

  21. Abushad M, Khan W, Naseem S, Husain S, Nadeem M, Ansari A (2019) Influence of Mn do** on microstructure, optical, dielectric and magnetic properties of BiFeO3 nanoceramics synthesized via sol–gel method. Ceram Int 45(6):7437–7445. https://doi.org/10.1016/j.ceramint.2019.01.035

    Article  Google Scholar 

  22. Chandel S, Thakur P, Tomar M, Gupta V, Thakur A (2017) Investigation of structural, optical, dielectric and magnetic studies of Mn substituted BiFeO3 multiferroics. Ceram Int 43(16):13750–13758. https://doi.org/10.1016/.j.ceramint.2017.07.088

    Article  Google Scholar 

  23. Hua, H., Bao, G., Li, C., Zhu, Y., Yang, J., & Li, X. A. (2017). Effect of Ho, Mn co-do** on the structural, optical and ferroelectric properties of nanoparticles. Journal of Materials Science: Materials in Electronics, J. Mater. Sci. Mater. Electron. 28(22), 17283–17287 https://doi.org/https://doi.org/10.1007/s10854-017-7660-5

  24. Liu T, Xu Y, Feng S, Zhao J (2011) A facile route to the synthesis of BiFeO3 at low temperature. J Am Ceram Soc 94(9):3060–3063. https://doi.org/10.1111/j.1551-2916.2011.04536.x

    Article  Google Scholar 

  25. Chen Z, Luo Z, Huang C, Qi Y, Yang P, You L, Hu C, Wu T, Wang J, Gao C, Sritharan T (2011) Low-symmetry monoclinic phases and polarization rotation path mediated by epitaxial strain in multiferroic BiFeO3 thin films. Adv Funct Mater 21(1):133–138. https://doi.org/10.1002/adfm.201001867

    Article  Google Scholar 

  26. Raj CA, Muneeswaran M, Jegatheesan P, Giridharan NV, Sivakumar V, Senguttuvan G (2013) Effect of annealing time in the low-temperature growth of BFO thin films spin coated on glass substrates. J Mater Sci Mater Electron 24(10):4148–4154. https://doi.org/10.1007/s10854-013-1374-0

    Article  Google Scholar 

  27. Rong N, Chu M, Tang Y, Zhang C, Cui X, He H, Zhang Y, **ao P (2016) Improved photoelectrocatalytic properties of Ti-doped BiFeO3 films for water oxidation. J Mater Sci 51(12):5712–5723. https://doi.org/10.1007/s10853-016-9873-z

    Article  Google Scholar 

  28. Gao F, Chen XY, Yin KB, Dong S, Ren ZF, Yuan F, Yu T, Zou ZG, Liu JM (2007) Visible-light photocatalytic properties of weak magnetic BiFeO3 nanoparticles. Adv Mater 19(19):2889–2892. https://doi.org/10.1002/adma.200602377

    Article  Google Scholar 

  29. Guo R, Fang L, Dong W, Zheng F, Shen M (2010) Enhanced photocatalytic activity and ferromagnetism in Gd doped BiFeO3 nanoparticles. J Phys Chem C 114(49):21390–21396. https://doi.org/10.1021/jp104660a

    Article  Google Scholar 

  30. Joshi UA, Jang JS, Borse PH, Lee JS (2008) Microwave synthesis of single-crystalline perovskite Bi Fe O3 nanocubes for photoelectrode and photocatalytic applications. Appl Phys Lett 92(24):242106. https://doi.org/10.1063/1.2946486

    Article  Google Scholar 

  31. Rhaman MM, Matin MA, Hossain MN, Mozahid FA, Hakim MA, Islam MF (2019) Bandgap engineering of cobalt-doped bismuth ferrite nanoparticles for photovoltaic applications. Bull Mater Sci 42(4):190. https://doi.org/10.1007/s12034-019-1871-8

    Article  Google Scholar 

  32. Lee JH, Ke X, Misra R, Ihlefeld JF, Xu XS, Mei ZG, Heeg T, Roeckerath M, Schubert J, Liu ZK, Musfeldt JL (2010) Adsorption-controlled growth of BiMnO3 films by molecular-beam epitaxy. Appl Phys Lett 96(26):262905. https://doi.org/10.1063/1.3457786

    Article  Google Scholar 

  33. Vishwakarma AK, Tripathi P, Srivastava A, Sinha AS, Srivastava ON (2017) Band gap engineering of Gd and Co doped BiFeO3 and their application in hydrogen production through photoelectrochemical route. Int J Hydrog Energy 42(36):22677–22686. https://doi.org/10.1016/j.ijhydene.2017.07.153

    Article  Google Scholar 

  34. Sati PC, Arora M, Chauhan S, Kumar M, Chhoker S (2014) Effect of Dy substitution on structural, magnetic and optical properties of BiFeO3 ceramics. J Phys Chem Solids 75(1):105–108. https://doi.org/10.1016/j.jpcs.2013.09.003

    Article  Google Scholar 

  35. Lin H, Huang CP, Li W, Ni C, Shah SI, Tseng YH (2006) Size dependency of nanocrystalline TiO2 on its optical property and photocatalytic reactivity exemplified by 2-chlorophenol. Appl Catal B 68(1–2):1–11. https://doi.org/10.1016/j.apcatb.2006.07.018

    Article  Google Scholar 

  36. Mocherla PS, Karthik C, Ubic R, Ramachandra Rao MS, Sudakar C (2013) Tunable bandgap in BiFeO3 nanoparticles: the role of microstrain and oxygen defects. Appl Phys Lett 103(2):022910. https://doi.org/10.1063/1.4813539

    Article  Google Scholar 

  37. Gómez-Salces S, Aguado F, Rodríguez F, Valiente R, González J, Haumont R, Kreisel J (2012) Effect of pressure on the band gap and the local FeO6 environment in BiFeO3. Phys Rev B 85(14):144109. https://doi.org/10.1103/PhysRevB.85.144109

    Article  Google Scholar 

  38. Song MG, Han JY, Bark CW (2015) The effect of annealing temperature on the bandgap of Bi3.25La0.75FeTi2O12 powders. J Nanosci Nanotechnol 15(10):8195–8198. https://doi.org/10.1166/jnn.2015.11275

    Article  Google Scholar 

  39. Irshad Z, Shah SH, Rafiq MA, Hasan MM (2015) First principles study of structural, electronic and magnetic properties of ferromagnetic Bi2Fe4O9. J Alloys Compd 624:131–136. https://doi.org/10.1016/j.jallcom.2014.10.174

    Article  Google Scholar 

Download references

Acknowledgements

We would like to thank DST-SERB(EMR/2017/002340) for supporting this project, and BITS Pilani, Hyderabad, for providing support and necessary infrastructure facilities. We also thank the Central Analytical Lab of BITS Pilani, Hyderabad, for providing all the characterization tools to make this work successfully in due time.

Author information

Authors and Affiliations

  1. Department of Physics, Birla Institute of Technology and Science (BITS) - Pilani, Hyderabad Campus, Hyderabad, 500078, India

    Waseem Ahmad Wani, Kannan Ramaswamy & B. Harihara Venkataraman

  2. Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science (BITS) - Pilani, Hyderabad Campus, Hyderabad, 500078, India

    Souvik Kundu

Authors
  1. Waseem Ahmad Wani
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Souvik Kundu
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Kannan Ramaswamy
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. B. Harihara Venkataraman
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

Waseem Ahmad Wani involved in conceptualization, methodology, investigation, writing—original draft and formal analysis. Souvik Kundu involved in writing—review and editing. Kannan Ramaswamy involved in writing—review and editing. B. Harihara Venkataraman involved in writing—review and editing and supervision.

Corresponding author

Correspondence to B. Harihara Venkataraman.

Ethics declarations

Conflict of interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Ethical standards

The authors have complied with ethical guidelines, the work described has not been published previously, and it is not under consideration for publication elsewhere. Its publication is approved by all authors, and if accepted, it will not be published elsewhere without the written consent of the Publisher. Sincerely, Harihara Venkataraman (Corresponding author, on behalf of all the other authors).

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Wani, W.A., Kundu, S., Ramaswamy, K. et al. Optimizing phase formation of BiFeO3 and Mn-doped BiFeO3 nanoceramics via thermal treatment using citrate precursor method. SN Appl. Sci. 2, 1969 (2020). https://doi.org/10.1007/s42452-020-03669-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s42452-020-03669-z

Keywords