本研究透過固相合成法製備 0.70BiFeO3-0.30BaTiO3 + 1 at% Mn (BF-BT)之固溶體，應用於壓電催化劑，並藉由結構與性能分析探討其在水汙染淨化中對六種不同汙染物的降解行為差異。材料分析結果顯示，BF-BT 處於 R3c 與 P4mm兩相共存之形態相邊界區(Morphotropic Phase Boundary, MPB)，兩相比例分別為69.7%和39.3%。此固溶體同時具備優異的壓電性能(d33=135 pC/N)與雙能隙特徵，分別對應 R3c相之 2.04 eV和P4mm相之3.53 eV。
在本實驗中所用的六種汙染物包括亞甲基藍、 孔雀石綠、 甲基橙、 羅丹明 B、 羅丹明 6G 和甲硝唑。其中，在壓電-光催化降解實驗中，BF-BT 對亞甲基藍和孔雀石綠展現出極佳的降解活性，降解效率在 120分鐘時分別達到94%和96%，這歸因於BF-BT表面負電性產生的靜電吸引、汙染物的降解路徑、分子結構特性，以及優化的電荷轉移路徑。為進一步提升催化降解效率，本實驗透過摻雜不同元素(La, Ni, Cu, Zr)進行研究，結果顯示，Cu 與 Ni 摻雜能有效調控能帶結構並抑制載子複合，將BF-BT:Ni 和 BF-BT:Cu的降解效率提升至 9798% ，擬一級速率常數(pseudo-first-order rate constant, k)為 0.0321 min-1。藉由自由基捕捉實驗和機制討論表明，BF-BT催化劑的壓電-光降解反應主要受超氧自由基與氫氧自由基作用。本研究深入討論了染料分子結構對降解速率的影響，同時也證實了透過材料工程調控壓電材料以及開發新穎多功能催化材料的可行性。

0.70BiFeO3-0.30BaTiO3 (BF-BT) solid-solutions show a morphotropic phase boundary (MPB) and exhibit a large piezoelectric effect. X-ray diffraction confirmed the coexistence of BF-based R3c phase and BT-based P4mm phase with the ratio 69.7%/30.3%. Piezoelectric measurements showed that the MPB samples indeed had a large d33 coefficient, which was 135 pC/N for the 0.70BF-0.30BT solution doped with 1 at% Mn. The Mn-doped BF-BT exhibited a high catalytic activity against MB and MG, which showed a degradation efficiency of 94% and 96%, respectively. Scavenger tests were carried out and the results indicated that the piezo-photocatalytic process was primarily driven by superoxide and hydroxyl radicals. This is consistent with the synergic action of piezo-photocatalysis and can be well explained by the piezopotential-induced band tilting, which not only helps to reduce charge recombination rate, but also allows both photoexcited electrons and holes to be functional. To further enhance catalytic efficiency, the Mn-doped 0.70BF-0.30BT were co-doped with other TM elements, such as Ni, Cu, etc. The results indicated that Ni and Cu co-doping led to a higher piezo-photodegradation of MB, which exhibited a degradation efficiency of about 97-98% and a pseudo-first-order rate constant up to 0.0321 min-1. Photocurrent measurements revealed that the TM co-doped 0.70BF-0.30BT had higher photocurrent, which was attributed to lower recombination rate of the photoexcited charger carriers. As a result, a further enhancement in the piezo-photodegradation efficiency of MB was observed.

[1] Mohan, M., N.P. Shetti, and T.M. Aminabhavi, "Perovskites: A new generation electrode materials for storage applications," Journal of Power Sources, vol. 574, 2023.
[2] Li, Z., M. Yang, J.-S. Park, S.-H. Wei, J.J. Berry, and K. Zhu, "Stabilizing Perovskite Structures by Tuning Tolerance Factor: Formation of Formamidinium and Cesium Lead Iodide Solid-State Alloys," Chemistry of Materials, vol. 28, no. 1, pp. 284-292, 2015.
[3] Banoo, M., et al., "Bi(4)TaO(8)Cl as a New Class of Layered Perovskite Oxyhalide Materials for Piezopotential Driven Efficient Seawater Splitting," Nano Lett, vol. 22, no. 22, pp. 8867-8874, Nov 23 2022.
[4] Guo, S., N. Tian, F. Chen, Y. Zhang, and H. Huang, "Layered perovskite Bi7Fe2Ti2O17Cl: Universally efficient photo-piezocatalysis and mechanismic insight into the origin of polarity," Applied Surface Science, vol. 708, 2025.
[5] Zhang, Y., et al., "Strategic B-site cation engineering in Sillen-Aurivillius perovskite oxyhalides for ultra-high efficiency piezocatalytic H(2)O(2) production," Mater Horiz, Feb 25 2026.
[6] Shimada, T., et al., "Multiferroic nature of intrinsic point defects inBiFeO3: A hybrid Hartree-Fock density functional study," Physical Review B, vol. 93, no. 17, 2016.
[7] Einarsrud, M.A. and T. Grande, "1D oxide nanostructures from chemical solutions," Chem Soc Rev, vol. 43, no. 7, pp. 2187-99, Apr 7 2014.
[8] Selbach, S.M., M.A. Einarsrud, and T. Grande, "On the Thermodynamic Stability of BiFeO3," Chemistry of Materials, vol. 21, no. 1, pp. 169-173, Jan 13 2009.
[9] Gutiérrez‐Lázaro, C., et al., "Solution Synthesis of BiFeO3 Thin Films onto Silicon Substrates with Ferroelectric, Magnetic, and Optical Functionalities," Journal of the American Ceramic Society, vol. 96, no. 10, pp. 3061-3069, 2013.
[10] Lu, S.Z., X. Qi, and P. Joy, "Magnetic and Dielectric Properties of Nanostructured BiFeO3 Prepared by Sol–Gel Method," Journal of the American Ceramic Society, vol. 97, no. 7, pp. 2185-2194, 2014.
[11] Tong, T., J. Chen, D. Jin, and J. Cheng, "Preparation and gas sensing characteristics of BiFeO 3 crystallites," Materials Letters, vol. 197, pp. 160-162, 2017.
[12] Bernardo, M.S., "Synthesis, microstructure and properties of BiFeO₃-based multiferroic materials: A review," Boletín de la Sociedad Española de Cerámica y Vidrio, vol. 53, no. 1, pp. 1-14, 2014.
[13] Haertling, G.H., "Ferroelectric Ceramics: History and Technology," Journal of the American Ceramic Society, vol. 82, no. 4, pp. 797-818, 2004.
[14] Jin, L., F. Li, S. Zhang, and D.J. Green, "Decoding the Fingerprint of Ferroelectric Loops: Comprehension of the Material Properties and Structures," Journal of the American Ceramic Society, vol. 97, no. 1, pp. 1-27, 2013.
[15] Mason, W.P., "Piezoelectricity, its history and applications," The Journal of the Acoustical Society of America, vol. 70, no. 6, pp. 1561-1566, 1981.
[16] Arnau, A. and D. Soares, Fundamentals of Piezoelectricity, in Piezoelectric Transducers and Applications. 2008. p. 1-38.
[17] Panda, P.K., Piezoceramic Materials and Devices for Aerospace Applications, in Aerospace Materials and Material Technologies, Vol 1: Aerospace Materials, N.E. Prasad and R.J.H. Wanhill, Editors. 2017. p. 501-518.
[18] Hahn, T. and H. Klapper, Crystallographic and noncrystallographic point groups, in International Tables for Crystallography Volume A: Space-group symmetry. 2006, Springer. p. 762-803.
[19] Mishra, S., L. Unnikrishnan, S.K. Nayak, and S. Mohanty, "Advances in Piezoelectric Polymer Composites for Energy Harvesting Applications: A Systematic Review," Macromolecular Materials and Engineering, vol. 304, no. 1, 2018.
[20] Liu, S.H., B. Shen, H.S. Hao, and J.W. Zhai, "Glass-ceramic dielectric materials with high energy density and ultra-fast discharge speed for high power energy storage applications," Journal of Materials Chemistry C, vol. 7, no. 48, pp. 15118-15135, Dec 28 2019.
[21] Kim, S., H. Nam, and I. Calisir, "Lead-Free BiFeO(3)-Based Piezoelectrics: A Review of Controversial Issues and Current Research State," Materials (Basel), vol. 15, no. 13, Jun 21 2022.
[22] Wang, J.J., F.Y. Meng, X.Q. Ma, M.X. Xu, and L.Q. Chen, "Lattice, elastic, polarization, and electrostrictive properties of BaTiO3 from first-principles," Journal of Applied Physics, vol. 108, no. 3, Aug 1 2010, Art no. 034107.
[23] Wang, Q., H.Z. Yan, X. Zhao, and C.M. Wang, "Polymorphic Phase Transition and Piezoelectric Performance of BaTiO3-CaSnO3 Solid Solutions," Actuators, vol. 10, no. 6, Jun 2021, Art no. 129.
[24] Li, H., et al., "Enhanced ferroelectric-nanocrystal-based hybrid photocatalysis by ultrasonic-wave-generated piezophototronic effect," Nano Lett, vol. 15, no. 4, pp. 2372-9, Apr 8 2015.
[25] Deka, B. and K.H. Cho, "BiFeO(3)-Based Relaxor Ferroelectrics for Energy Storage: Progress and Prospects," Materials (Basel), vol. 14, no. 23, Nov 25 2021.
[26] Guo, R., L.E. Cross, S.E. Park, B. Noheda, D.E. Cox, and G. Shirane, "Origin of the high piezoelectric response in PbZr1-xTixO3," Physical Review Letters, vol. 84, no. 23, pp. 5423-5426, Jun 5 2000.
[27] Jain, A., Y.G. Wang, and L.N. Shi, "Recent developments in BaTiO3 based lead-free materials for energy storage applications," Journal of Alloys and Compounds, vol. 928, Dec 20 2022, Art no. 167066.
[28] Sood, A., et al., "A Comprehensive Review on Barium Titanate Nanoparticles as a Persuasive Piezoelectric Material for Biomedical Applications: Prospects and Challenges," Small, vol. 19, no. 12, Mar 2023.
[29] Masekela, D., N.C. Hintsho-Mbita, S. Sam, T.L. Yusuf, and N. Mabuba, "Application of BaTiO3-based catalysts for piezocatalytic, photocatalytic and piezo- photocatalytic degradation of organic pollutants and bacterial disinfection in wastewater: A comprehensive review," Arabian Journal of Chemistry, vol. 16, no. 2, Feb 2023, Art no. 104473.
[30] Wang, X.S., Y. Zhou, Y. Jiang, and C. Sun, "The removal of basic dyes from aqueous solutions using agricultural by-products," J Hazard Mater, vol. 157, no. 2-3, pp. 374-85, Sep 15 2008.
[31] Haleem, A., et al., "In-Depth Photocatalytic Degradation Mechanism of the Extensively Used Dyes Malachite Green, Methylene Blue, Congo Red, and Rhodamine B via Covalent Organic Framework-Based Photocatalysts," Water, vol. 16, no. 11, 2024.
[32] Sankar Sana, S., R. Haldhar, J. Parameswaranpillai, M. Chavali, and S.-C. Kim, "Silver nanoparticles-based composite for dye removal: A comprehensive review," Cleaner Materials, vol. 6, 2022.
[33] Donga, C., R. Ratshiedana, A.T. Kuvarega, N. Masunga, V.S. Vallabhapurapu, and P. Mbule, "Photocatalytic degradation of organic pollutants in wastewater using magnetic functionalized reduced graphene oxide nanocomposites. A review," Talanta, vol. 295, p. 128318, Dec 1 2025.
[34] Khan, I., et al., "Review on Methylene Blue: Its Properties, Uses, Toxicity and Photodegradation," Water, vol. 14, no. 2, 2022.
[35] Arif, M., "Catalytic reduction/degradation of methyl orange by metal nanoparticle containing systems: a critical review," RSC Adv, vol. 15, no. 34, pp. 27668-27684, Aug 1 2025.
[36] Prabakaran, R. and S. Arivoli, "Thermodynamic and Isotherm Analysis on the Removal of Malachite Green Dye Using Thespesia Populnea Bark," Journal of Chemistry, vol. 9, no. 4, pp. 2575-2588, 2012.
[37] Mohod, A.V., et al., "Degradation of Rhodamine dyes by Advanced Oxidation Processes (AOPs) – Focus on cavitation and photocatalysis - A critical review," Water Resources and Industry, vol. 30, 2023.
[38] Meena, P.L., J.K. Saini, A.K. Surela, K. Poswal, and L.K. Chhachhia, "Fabrication of polyaniline-coated porous and fibrous nanocomposite with granular morphology using tea waste carbon for effective removal of rhodamine B dye from water samples," Biomass Conversion and Biorefinery, vol. 14, no. 2, pp. 1711-1730, 2022.
[39] Majeed, J., J. Ramkumar, S. Chandramouleeswaran, O.D. Jayakumar, and A.K. Tyagi, "Kinetic modeling: dependence of structural and sorption properties of ZnO—crucial role of synthesis," RSC Advances, vol. 3, no. 10, 2013.
[40] Dingsdag, S.A. and N. Hunter, "Metronidazole: an update on metabolism, structure-cytotoxicity and resistance mechanisms," Journal of Antimicrobial Chemotherapy, vol. 73, no. 2, pp. 265-279, Feb 2018.
[41] Suvarna, V., M. Murahari, and S. Pawar, "Metronidazole-An Old Drug for Structure Optimization and Repurposing," Chemistry & Biodiversity, vol. 22, no. 10, Oct 2025.
[42] Kumari, H., et al., "A Review on Photocatalysis Used For Wastewater Treatment: Dye Degradation," Water Air Soil Pollut, vol. 234, no. 6, p. 349, 2023.
[43] Ibhadon, A.O. and P. Fitzpatrick, "Heterogeneous photocatalysis: recent advances and applications," Catalysts, vol. 3, no. 1, pp. 189-218, 2013.
[44] Jimenez-Lopez, L., R.M. Ospino, L.G. de Araujo, A. Celzard, and V. Fierro, "Latest developments in the synthesis of metal–organic frameworks and their hybrids for hydrogen storage," Nanoscale, vol. 17, no. 11, pp. 6390-6413, 2025.
[45] Li, S., Y. Li, and H. Huang, "Solar‐Driven Selective Oxidation Over Bismuth‐Based Semiconductors: From Prolific Catalysts to Diverse Reactions," Advanced Functional Materials, vol. 34, no. 27, 2024.
[46] Low, J., J. Yu, M. Jaroniec, S. Wageh, and A.A. Al-Ghamdi, "Heterojunction Photocatalysts," Advanced Materials, vol. 29, no. 20, p. 1601694, 2017.
[47] Bard, A.J., "Photoelectrochemistry and heterogeneous photo-catalysis at semiconductors," Journal of photochemistry, vol. 10, no. 1, pp. 59-75, 1979.
[48] Tada, H., T. Mitsui, T. Kiyonaga, T. Akita, and K. Tanaka, "All-solid-state Z-scheme in CdS–Au–TiO2 three-component nanojunction system," Nature materials, vol. 5, no. 10, pp. 782-786, 2006.
[49] Yu, J., S. Wang, J. Low, and W. Xiao, "Enhanced photocatalytic performance of direct Z-scheme gC 3 N 4–TiO 2 photocatalysts for the decomposition of formaldehyde in air," Physical Chemistry Chemical Physics, vol. 15, no. 39, pp. 16883-16890, 2013.
[50] Zu, D., et al., "The role of point defects in heterojunction photocatalysts: perspectives and outlooks," Advanced Functional Materials, vol. 34, no. 48, p. 2408213, 2024.
[51] Ali, S. and T. Ahmad, "Treasure trove for efficient hydrogen evolution through water splitting using diverse perovskite photocatalysts," Materials Today Chemistry, vol. 29, p. 101387, 2023.
[52] Zhu, D., Z. Dong, F. Lv, C. Zhong, and W. Huang, "The development of balanced heterojunction photocatalysts," Cell Reports Physical Science, vol. 3, no. 10, 2022.
[53] Dolla, T.H., T. Matthews, N.W. Maxakato, P. Ndungu, and T. Montini, "Recent advances in transition metal sulfide-based electrocatalysts and photocatalysts for nitrogen fixation," Journal of Electroanalytical Chemistry, vol. 928, p. 117049, 2023.
[54] Ali, S., J.A. Nasir, R.N. Dara, and Z. Rehman, "Modification strategies of metal oxide photocatalysts for clean energy and environmental applications: A review," Inorganic Chemistry Communications, vol. 145, p. 110011, 2022.
[55] Lee, D.-E., M.-K. Kim, M. Danish, and W.-K. Jo, "State-of-the-art review on photocatalysis for efficient wastewater treatment: Attractive approach in photocatalyst design and parameters affecting the photocatalytic degradation," Catalysis Communications, vol. 183, p. 106764, 2023.
[56] Becker, C., "From Langmuir to Ertl: The “Nobel” history of the surface science approach to heterogeneous catalysis," encyclopedia of interfacial chemistry, pp. 99-106, 2018.
[57] Qi, W., et al., "Advancements and opportunities in piezo-(photo) catalytic synthesis of value-added chemicals," EES Catalysis, vol. 2, no. 4, pp. 884-910, 2024.
[58] Jin, C.C., D.M. Liu, and L.X. Zhang, "An emerging family of piezocatalysts: 2D piezoelectric materials," Small, vol. 19, no. 44, p. 2303586, 2023.
[59] Jin, C.C., D.M. Liu, and L.X. Zhang, "An Emerging Family of Piezocatalysts: 2D Piezoelectric Materials," Small, vol. 19, no. 44, p. e2303586, Nov 2023.
[60] Jia, P., J. Li, and H. Huang, "Piezocatalysts and Piezo‐Photocatalysts: From Material Design to Diverse Applications," Advanced Functional Materials, vol. 34, no. 44, 2024.
[61] Bößl, F., et al., "Effect of frequency and power on the piezocatalytic and sonochemical degradation of dyes in water," Chemical Engineering Journal Advances, vol. 14, p. 100477, 2023.
[62] McKenzie, T.G., F. Karimi, M. Ashokkumar, and G.G. Qiao, "Ultrasound and Sonochemistry for Radical Polymerization: Sound Synthesis," Chemistry, vol. 25, no. 21, pp. 5372-5388, Apr 11 2019.
[63] Guo, M., et al., "Highly-efficient photocatalytic hydrogen evolution enabled by piezotronic effects in SrTiO3/BaTiO3 nanofiber heterojunctions," Nano Energy, vol. 127, p. 109745, 2024.
[64] Feng, J., T. Yan, and Z. Hou, "Numerical Simulation Study of Factors Influencing Ultrasonic Cavitation Bubble Evolution on Rock Surfaces during Ultrasonic-Assisted Rock Breaking," Water, vol. 16, no. 16, p. 2234, 2024.
[65] Fei, H.L., et al., "Strategies for enhancing activities of typical piezo-photocatalytic material and its applications in environmental remediation: A review," Journal of Environmental Chemical Engineering, vol. 12, no. 1, Feb 2024, Art no. 111650.
[66] Dhiman, P., J. Sharma, A. Kumar, G. Sharma, G. Rana, and G.T. Mola, "Recent advances in piezo-photocatalytic heterojunctions for energy and environmental applications," Materials Today Sustainability, vol. 28, Dec 2024, Art no. 100973.
[67] He, J., et al., "Review of piezocatalysis and piezo-assisted photocatalysis in environmental engineering," Crystals, vol. 13, no. 9, p. 1382, 2023.
[68] Jia, P., J. Li, and H. Huang, "Piezocatalysts and piezo‐photocatalysts: from material design to diverse applications," Advanced Functional Materials, vol. 34, no. 44, p. 2407309, 2024.
[69] Pan, Q., et al., "Piezo-photocatalysis of Sr-doped Bi4O5Br2/Bi2MoO6 composite nanofibers to simultaneously remove inorganic and organic contaminants," Journal of Water Process Engineering, vol. 56, p. 104330, 2023.
[70] Wan, L.C., J. Han, W.R. Tian, N.J. Li, D.Y. Chen, and J.M. Lu, "Barium titanate@covalent organic framework core-shell nanoparticles for adsorption-enhanced piezo-photocatalysis," Chemical Engineering Journal, vol. 462, Apr 15 2023, Art no. 142324.
[71] Wang, J. and S. Wang, "Reactive species in advanced oxidation processes: Formation, identification and reaction mechanism," Chemical Engineering Journal, vol. 401, 2020.
[72] Fónagy, O., E. Szabó-Bárdos, and O. Horváth, "1,4-Benzoquinone and 1,4-hydroquinone based determination of electron and superoxide radical formed in heterogeneous photocatalytic systems," Journal of Photochemistry and Photobiology A: Chemistry, vol. 407, 2021.
[73] Ul-Hamid, A., Components of the SEM, in A Beginners' Guide to Scanning Electron Microscopy. 2018, Springer. p. 15-76.
[74] Ezzahmouly, M., et al., "Micro-computed tomographic and SEM study of porous bioceramics using an adaptive method based on the mathematical morphological operations," Heliyon, vol. 5, no. 12, 2019.
[75] Harrington, G.F. and J. Santiso, "Back-to-Basics tutorial: X-ray diffraction of thin films," Journal of Electroceramics, vol. 47, no. 4, pp. 141-163, 2021.
[76] Rocha, F.S., A.J. Gomes, C.N. Lunardi, S. Kaliaguine, and G.S. Patience, "Experimental methods in chemical engineering: Ultraviolet visible spectroscopy—UV‐Vis," The Canadian Journal of Chemical Engineering, vol. 96, no. 12, pp. 2512-2517, 2018.
[77] Hu, C.-J., F.-C. Fan, S.-W. Wu, and X. Qi, "Improved piezo-photodegradation efficiency of BiFeO3–BaTiO3 solid solutions in the morphotropic phase boundary region," Journal of Materials Science, 2026.
[78] Chen, H., B. Shen, J. Xu, L. Kong, and J. Zhai, "Correlation between grain sizes and electrical properties of CaBi2Nb2O9 piezoelectric ceramics," Journal of the American Ceramic Society, vol. 95, no. 11, pp. 3514-3518, 2012.
[79] Zhang, H., et al., "The grain size effect on the properties of Aurivillius phase Bi3. 15Nd0. 85Ti3O12 ferroelectric ceramics," Nanotechnology, vol. 20, no. 38, p. 385708, 2009.
[80] Wang, D., et al., "BiFeO3-BaTiO3: A new generation of lead-free electroceramics," Journal of advanced dielectrics, vol. 8, no. 06, p. 1830004, 2018.
[81] Basith, M.A., N. Yesmin, and R. Hossain, "Low temperature synthesis of BiFeO3nanoparticles with enhanced magnetization and promising photocatalytic performance in dye degradation and hydrogen evolution," RSC Advances, vol. 8, no. 52, pp. 29613-29627, 2018.
[82] Hao, S., et al., "Optical absorption by design in a ferroelectric: co-doping in BaTiO3," Journal of Materials Chemistry C, vol. 10, no. 1, pp. 227-234, 2022.
[83] Rasheed, T., M. Bilal, H.M.N. Iqbal, H. Hu, and X. Zhang, "Reaction Mechanism and Degradation Pathway of Rhodamine 6G by Photocatalytic Treatment," Water, Air, & Soil Pollution, vol. 228, no. 8, 2017.
[84] Li, Y.-F., W.-P. Zhang, X. Li, and Y. Yu, "TiO2 nanoparticles with high ability for selective adsorption and photodegradation of textile dyes under visible light by feasible preparation," Journal of Physics and Chemistry of Solids, vol. 75, no. 1, pp. 86-93, 2014/01/01/ 2014.
[85] Xu, B., X. Wang, C. Zhu, X. Ran, T. Li, and L. Guo, "Probing the inhomogeneity and intermediates in the photosensitized degradation of rhodamine B by Ag3PO4 nanoparticles from an ensemble to a single molecule approach," RSC Advances, vol. 7, no. 65, pp. 40896-40904, 2017.
[86] Mulliken, R.S., "A New Electroaffinity Scale; Together with Data on Valence States and on Valence Ionization Potentials and Electron Affinities," The Journal of Chemical Physics, vol. 2, no. 11, pp. 782-793, 1934.
[87] Pearson, R.G., "Absolute electronegativity and hardness: application to inorganic chemistry," Inorganic chemistry, vol. 27, no. 4, pp. 734-740, 1988.