Lead-based Materials Research Articles

Lead-free perovskite solar cell byUsing SCAPS-1D: Design and simulation

The efficiency of photovoltaic systems of perovskite materials based on organic–inorganic halide has increased and they are nearing commercialization. Lead-free perovskite materials have recently attracted the interest of researchers and the scientific community due to the toxicity issue and harmful lead-based perovskite materials. Tin, like lead (Pb) is a group 14 metals; hence, it is the most likely substitute. We use SCAPS-1D numerical simulation to optimize the device efficiency of a lead-free n-i-p based planar hetrostructure perovskite solar cell composed of intrinsic-CH3NH3SnI3 methyl ammonium tin iodide (MASnI3) as an i- and p-layer Spiro-OMeTAD with SnO2 for the n layer. Conclusions show that the absorber layer has a thickness of 600 nm, which is required for optimal cell performance and efficiency. The thickness and defect density of this absorber layer was taken into account, absorption coefficient is inversely proportional to defect density. The performance of device worsens when the defect density of absorber layer increases. The thickness and defect density of absorber layer was carefully tuned to get maximum solar cell performance and we observed an efficiency of 22.21 %, current density (JSC) of 33.8636 mA/cm2, VOC of 0.989 V and FF of 66.33 % at 600 nm thickness of absorber layer.

Dual Functions of Performance Improvement and Lead Leakage Mitigation of Perovskite Solar Cells Enabled by Phenylbenzimidazole Sulfonic Acid.

With the continuous improvement of performance of lead-based perovskite solar cells (PSCs), the potential harm of water-soluble lead ion (Pb2+ ) to environment and public health is emerging as a major obstacle to their commercialization. Herein, an amphoteric phenylbenzimidazole sulfonic acid (PBSA) that is almost insoluble in water is added to the perovskite precursor to simultaneously regulate crystallization growth, passivate defects, and mitigate lead leakage of high-performance PSCs. Through systematic research, it is found that PBSA can not only regulate the crystallization of perovskite grains to form the film, but also passivate the defects of annealed films mainly due to the strong interaction between the functional groups in PBSA and Pb2+ , which greatly improves the crystallinity and stability of perovskite films. Consequently, the highest power conversion efficiency of 23.27% is achieved in 0.09 cm2 devices and 15.31% is obtained for large-area modules with an aperture area of 19.32 cm2 , along with negligible hysteresis and improved stability. Moreover, the leakage of lead ions from unpackaged devices is effectively prevented owing to the strong coupling between PBSA molecules and water-soluble Pb2+ to form insoluble complexes in water, which is of great significance to promote the application of optoelectronic devices based on lead-based perovskite materials.

Feasible Way to Achieve Multifunctional (K, Na)NbO3-Based Ceramics: Controlling Long-Range Ferroelectric Ordering.

It is challenging to achieve highly tunable multifunctional properties in one piezoelectric ceramic system through a simple method due to the complicated relationship between the microscopic structure and macroscopic property. Here, multifunctional potassium sodium niobate [(K, Na)NbO3 (KNN)]-based lead-free piezoceramics with tunable piezoelectric and electrostrictive properties are achieved by controlling the long-range ferroelectric ordering (LRFO) through antimony (Sb) doping. At a low Sb doping, the slightly distorted NbO6 octahedron and the softened B-O repulsion well maintain the LRFO and induce plenty of nanoscale domains coexisting with a few polar nanoregions (PNRs). Thereby, the diffused rhombohedral-orthorhombic-tetragonal (R-O-T) multiphase coexistence with distinct dielectric jumping is constructed near room temperature, by which the nearly 2-fold increase in the piezoelectric coefficient (d33 ∼ 539 pC/N) and the temperature-insensitive strain (the unipolar strain varies less than 8% at 27-120 °C) are obtained. At a high Sb doping, the LRFO is significantly destroyed, leading to predominant PNRs. Thus, a typical relaxor is obtained at the ferroelectric-paraelectric phase transition near room temperature, in which a large electrostrictive coefficient (Q33 = 0.035 m4/C2), independent of the electric field and temperature, is obtained and comparable to that of lead-based materials. Therefore, our results prove that controlling the LRFO is a feasible way to achieve high-performance multifunctional KNN-based ceramics and is beneficial to the future composition design for KNN-based ceramics.

Design and Development of a Lead-Freepiezoelectric Energy Harvester for Wideband, Low Frequency, and Low Amplitude Vibrations

In recent years, energy harvesting from ambient vibrations using piezoelectric materials has become the center of attention due to the fact that it has the potential to replace batteries, providing an easy way to power wireless and low power sensors and electronic devices. Piezoelectric material has been extensively used in energy harvesting technologies. However, the most commercially available and widely used piezoelectric materials are lead-based, Pb (PZT), which contains more than 60 weight percent lead (Pb). Due to its extremely hazardous effects on lead elements, there is a strong need to substitute PZT with new lead-free materials that have comparable properties to those of PZT. Lead-free lithium niobate (LiNbO3) piezoelectric material can be considered as a substitute for lead-based piezoelectric materials for vibrational energy scavenging applications. LiNbO3 crystal has a lower dielectric constant comparison to the conventional piezoceramics (for instance, PZT); however, at the same time, LiNbO3 (LN) single crystal presents a figure of merits similar to that of PZT, which makes it the most suitable choice for a vibrational energy harvester based on lead-free materials. The implementation was carried out using a global optimization approach including a thick single-crystal film on a metal substrate with optimized clamped capacitance for better impedance matching conditions. A lot of research shows that standard designs such as linear piezoelectric energy harvesters are not a prominent solution as they can only operate in a narrow bandwidth because of their single high resonant peak in their frequency spectrum. In this paper, we propose, and experimentally validate, a novel lead-free piezoelectric energy harvester to harness electrical energy from wideband, low-frequency, and low-amplitude ambient vibration. To reach this target, the harvester is designed to combine multi-frequency and nonlinear techniques. The proposed energy harvesting system consists of six piezoelectric cantilevers of different sizes and different resonant frequencies. Each is based on lead-free lithium niobate piezoelectric material coupled with a shape memory alloy (nitinol) substrate. The design is in the form of a circular ring to which the cantilevers are embedded to create nonlinear behavior when excited with ambient vibrations. The finite element simulation and the experimental results confirm that the proposed lead-free harvester design is efficient at low frequencies, particularly different frequencies below 250 Hz.

Recent Advances in Tin-based Hybrid Organic-Inorganic PSCs: Additives for Improved Stability and Performance

Perovskite solar cells (PSCs) materials are progressing as potential candidates for the future generation of photovoltaics. Despite the most efficient photovoltaic performance, lead-based perovskite materials are not considered for commercialization due to the high toxicity of lead. One of the promising alternatives is tin (Sn)-based perovskites, which exhibits equivalent ionic size as lead and outstanding absorption properties. However, Sn-based perovskite materials have stability and low-performance issues because of the easy oxidation of Sn2+ to Sn4+and fast crystallization. This paper gives a focused overview of the notable recent studies to address the stability and low-performance challenges of Sn-based hybrid organic-inorganic perovskite (Sn-HOIP) materials for solar cells by using functional additives. To date, the addition of SnF2 additive in the methylammonium tin iodide-based PSCs has shown the highest efficiency of 7.78% and maintains 70% of original efficiency over 200-hours. In the case of formamidinium tin iodide-based PSCs, the addition of phenylhydrazine hydrochloride significantly increases the power conversion efficiency to 11.40% from 5.60% for a pristine device. However, further improvement in the stability and efficiency of Sn-based PSCs requires a molecular-level understanding of the role of existing and new candidates of additives tailored for evolving Sn-HOIP materials.

Li and Ta-modified KNN piezoceramic fibers for vibrational energy harvesters

Piezoelectric energy harvesters (PEH) hold enormous potential for converting mechanical energy from our surrounding environment into electrical energy that can be used for powering portable electronics. Potassium sodium niobate (KNN) is one of the promising alternatives to replace lead-based piezoelectric materials. This work presents a cutting-edge demonstration of synthesis-function-device integration of piezoelectric nanofibers, where the morphology and the composition are engineered towards achieving high device output. We report a flexible nanogenerator based on electrospun Li and Ta-modified lead-free KNN nanofibers yielding a high voltage output of 5.6 V, which is around 9-fold higher than for the Mn-doped KNN nanofibers reported previously. The influence of Li and Ta-incorporation into the KNN lattice on the electromechanical coupling and the effect of a nanofiber morphology are investigated. The net-shaped KNN and Li and Ta-modified KNN nanofibers, synthesized by electrospinning of appropriate sols, maintain their structural integrity upon calcination and firing steps. The phase analysis (XRD) confirms the formation of single-phase (KNN) material. Li and Ta are found to be incorporated on the A and B-sites of the perovskite lattice, respectively. Piezo force microscopy data show the heat-treated nanofibers to exhibit multi-domain ferroelectric properties.

Processing Optimization and Toxicological Evaluation of "Lead-Free" Piezoceramics: A KNN-Based Case Study.

Due to the ever-increasing limitations of the use of lead-based materials, the manufacturing of lead-free piezoceramics with competitive piezoelectric properties and established nontoxicity is considered a priority for the scientific and industrial community. In this work, a lead-free system based on sodium potassium niobate (KNN), opportunely modified with MgNb2O6 (MN), was prepared through a combination of a mechanochemical activation method and air sintering, and its toxicity was evaluated. The effect of the mechanical processing on the microstructure refinement of the processed powders was established by X-ray diffraction and the average crystallite size content of the Nb2O5 species was evaluated. The experimental evidence was rationalized using a phenomenological model which permitted us to obtain the amount of powder processed at each collision and to optimize the activation step of the pre-calcined reagents. This influenced the final density and piezoresponse of the as-sintered pellets, which showed optimal properties compared with other KNN systems. Their toxicological potential was evaluated through exposure experiments to the pulverized KNN-based pellets, employing two widely used human and environmental cellular models. The in vitro assays proved, under the selected conditions, the absence of cytotoxicity of KNN-bases systems here studied.

Numerical Modeling and Optimization of Lead-Free Hybrid Double Perovskite Solar Cell by Using SCAPS-1D

The highest power conversion efficiency (PCE) for organic-inorganic perovskite solar cells based on lead is reported as 25.2% in 2019. Lead-based hybrid perovskite materials are used in several photovoltaics applications, but these are not highly favored due to the toxicity of lead and volatility of organic cations. On the other hand, hybrid lead-free double perovskite has no such harm. In this research study, SCAPS numerical simulation is utilized to evaluate and compare the results of perovskite solar cell based on double perovskite FA 2 BiCuI 6 and standard perovskite CH 3 NH 3 PbI 3 as an active layer. The results show that the power conversion efficiency obtained in the case of FA 2 BiCuI 6 is 24.98%, while in the case of CH 3 NH 3 PbI 3 , it is reported as 26.42%. This indicates that the hybrid organic-inorganic double perovskite FA 2 BiCuI 6 has the ability to replace hybrid organic-inorganic perovskite CH 3 NH 3 PbI 3 to expand next-generation lead-free harmless materials for solar cell applications.

Stability Enhancement of Pbo-Based Anodes through Facile Encapsulation in Carbon Nanofibers for Li-Ion Batteries

Lead (II) Oxide (PbO)-embedded Carbon Nanofiber (CNF) anodes for lithium-ion batteries were prepared via the electrospinning method. While lead-based materials have several advantages over conventional graphite, including higher theoretical capacity and low cost, deleterious performance loss due to degradation caused by volume expansion remains as its main limitation. The use of carbon as an additive has been shown to stabilize the cycling performance and utilizing carbon nanostructures, namely nanofibers, can further substantially improve performance by accommodating volume change during lithiation/de-lithiation upon cycling as well as of batteries through capacity retention over several cycles. In this report, significant enhancement of battery performance in terms of specific capacity and cyclability is made using the prepared PbO/CNF anodes. The PbO particles were effectively embedded into the CNF, which significantly suppressed mechanical degradation of the electrode due to volume expansion and retained the PbO particles over numerous cycles and at high current. The PbO/CNF anode exhibits a high specific capacity of 375 mAh g-1 at a current of 200 mA g-1 (corresponding to ~1.2C) over 250 cycles compared 245 mAh g-1 for CNF, high current capability, and markedly improved stability, indicating its potential as an alternative to conventional graphite anodes.

Performance optimization of lead free-MASnI3 based solar cell with 27% efficiency by numerical simulation

Abstract The photovoltaic devices based on organic-inorganic halide perovskite materials have witnessed a rapid increase in performance and are marching towards commercialization. Recently, lead-free perovskites have drawn huge attention as one of the major research topics over toxic lead-based materials. Here, we report the optimized device performance of methylammonium tin iodide (MASnI3) based perovskite solar cell by using numerical simulation. The influence of different key parameters, such as different hole transport layers (HTLs), doping density, thickness of different layers including defect density on the device performances is thoroughly analysed through numerical simulation. The optimized device architecture with copper (I) oxide (Cu2O) as the hole transport layer and TiO2 as electron transport layer shows the highest power conversion efficiency of 27.43%, short circuit current density of 25.97 mA/cm2, open-circuit voltage of 1.203 V, and fill factor of 87.79%. This indicates that by optimizing the device parameters, it is possible to achieve high performance lead-free perovskite solar cells experimentally in future research.

Enhanced energy storage efficiency by modulating field-induced strain in BaTiO3-Bi(Ni2/3Ta1/3)O3 lead-free ceramics

Nowadays, more attention has been paid to nontoxic lead-free ferroelectric (FE) materials as the substitution of lead-based energy storage materials, due to the increasing environmental awareness. BaTiO3 (BT) has good comprehensive properties, however, its low breakdown electric field leads to the low energy storage density, which is the main challenge in BT-based ceramics. In this work, BT was modified by introducing the Bi(Ni2/3Ta1/3)O3 (BNT) component in order to reduce the field-induced strain and further enhance the breakdown strength. Effects of BNT component on the microstructures, relaxor characteristics, energy storage efficiency and field-induced strain were investigated systematically. The results indicate that the long-range ordered ferroelectric domains of BT ceramics are destroyed by the incorporation of the BNT component, resulting in the distortion of the polar regions. As a result, the BT-BNT ceramics possess slim P-E hysteresis and extremely low remnant polarization, owing to the phase transition from the normal ferroelectrics to relaxor ferroelectrics. The reduced strain promotes to the increase of the breakdown field strength. Ultimately, the energy storage efficiency of BT-BNT ceramics can reach 87.15%, revealing a promising application in energy storage device.

Structural and dielectric properties of pure potassium sodium niobate (KNN) lead free ceramics

Lead free KNN (K0·5Na0·5NbO3) ceramics was obtained via the conventional solid state sintering technique. The ceramics synthesized was characterized for their phase transition analysis, crystal structure, morphology and electrical properties. The powder X-ray diffraction (XRD) patterns confirmed single phase of KNN with orthorhombic crystal system at room temperature. Scanning electron microscopy (SEM) of the sintered KNN revealed the existence of densification and comparable size of the grains. Two phase transitions were observed in ϵr-T graph: orthorhombic to tetragonal at TO-T (~236 °C) and tetragonal to cubic at TT-C (~440 °C) for 1 kHz frequency. The decrease in the net polarization of the material with the increase in frequency leads to the decrease in the value of ϵr and tanδ. Three characteristic Raman peaks observed at (~262 cm−1, ~617 cm−1 and ~858 cm−1) correlate the structure and ferroelectric properties of KNN materials. These promising outcomes demonstrate that KNN-based lead-free ceramic composition is potential candidate to substitute lead-based materials for various applications.

Large-scale room-temperature synthesis of high-efficiency lead-free perovskite derivative (NH4)2SnCl6:Te phosphor for warm wLEDs

• Perovskite (NH 4 ) 2 Sn 1-x Te x Cl 6 phosphors were developed for solid-state lighting. • The phosphors show broad orange emission with high PLQY (FWHM: 127 nm; PLQY: 84%). • The structure–property relations were revealed. • The excellent warm wLED was created using the title phosphors. Low-dimensional lead-based perovskite materials have recently attracted extensive attentions for their diverse structures, unique optoelectronic properties and enhanced stability. However, the toxicity of lead, low photoluminescence quantum yield (PLQY) and complex preparation processes limit their practical applications. Herein, we present a simple room-temperature synthesis of orange-emitting lead-free perovskite derivative (NH 4 ) 2 SnCl 6 :Te phosphors with a large quantity at one time. By introducing Te 4+ ions with 5s 2 active lone pairs, (NH 4 ) 2 SnCl 6 :Te exhibits broadband emission peaked at 590 nm, a large full width at half maximum (FWHM) about 127 nm and a maximum PLQY up to 83.51%. Density functional theory calculations combined with comprehensive spectroscopic data reveal that the incorporated Te 4+ ions change the band structure and trigger the formation of Jahn-Teller-like self-trapped excitons (STEs) in [TeCl 6 ] 2− centers. In addition, (NH 4 ) 2 SnCl 6 :Te shows excellent ambient and thermal stabilities. Using (NH 4 ) 2 SnCl 6 :0.5%Te as an orange down-conversion material, highly stable wLEDs with a Commission Internationale de l’Eclairage (CIE) of (0.39, 0.38), correlated color temperature (CCT) of 3855 K, and color rendering index (CRI) of 83 are demonstrated. We expect these results to facilitate the development of low-cost, environmentally friendly and high-performance novel phosphors for future lighting and display technologies.

A novel (La0.2Ce0.2Gd0.2Er0.2Tm0.2)2(WO4)3 high-entropy ceramic material for thermal neutron and gamma-ray shielding

In this study, a new type of (La0.2Ce0.2Gd0.2Er0.2Tm0.2)2(WO4)3 single-phase high-entropy ceramic (HEC) powder was designed, prepared by solid-phase synthesis, and evenly mixed into an epoxy resin (EP) matrix to test the thermal neutron and γ-ray shielding performance. In terms of γ-ray shielding, (La0.2Ce0.2Gd0.2Er0.2Tm0.2)2(WO4)3 showed a higher lead equivalent value than EP at 65 keV, indicating a clear shielding effect in the feeble absorbing area of lead-based and bismuth-based materials; moreover, (La0.2Ce0.2Gd0.2Er0.2Tm0.2)2(WO4)3 showed good γ-ray shielding performance in both low-energy and medium-energy regions. In terms of thermal neutron shielding, the composite with the highest HEC content (EP/W3) had a nearly 100% shielding efficiency, while that of EP was approximately 50%, indicating that this material has favorable thermal neutron and γ-ray shielding performance. Moreover, the thermal conductivity of the resulting composite material was lower than 0.3 W·m−1·K−1, the tensile strength was higher than 10 MPa, and the density was lower than 1.5 g·cm−3. All these results suggest that (La0.2Ce0.2Gd0.2Er0.2Tm0.2)2(WO4)3 is a candidate radiation shielding material.

Dark Self-Healing-Mediated Negative Photoconductivity of a Lead-Free Cs3Bi2Cl9 Perovskite Single Crystal.

Recently, halide perovskites have emerged as a promising material for device applications. Lead-based perovskites have been widely explored, while investigation of the optical properties of lead-free perovskites remains limited. Lead-halide perovskite single crystals have shown light-induced positive photoconductivity, and as lead-free perovskites are optically active, they are expected to demonstrate similar properties. However, we report here light-induced negative photoconductivity with slow recovery in lead-free Cs3Bi2Cl9 perovskite. Femtosecond transient reflectance (fs-TR) spectroscopy studies further reveal that these electronic transport properties are due to the formation of light-activated metastable trap states within the perovskite crystal. The figure of merits were calculated for Cs3Bi2Cl9 single-crystal detectors, including responsivity (17 mA/W), detectivity (6.23 × 1011 Jones), and the ratio of current in dark to light (∼7160). These observations for Cs3Bi2Cl9 single crystals, which were optically active but showed retroactive photocurrent on irradiation, remain unique for such materials.

Giant electrostrictive coefficient in rapidly cooled nanodisordered KTa1−xNbxO3 lead-free single crystals

The temperature dependent electrostrictive effect, with respect to increasing the cooling rate to a cooling temperature, was quantitatively investigated in potassium tantalate niobate (KTN) lead-free single crystals above and near Curie temperature (TC). High work-function Pt electrodes are used to minimize the effect of charge injection, and the electric field induced displacement was measured with Michelson interferometry. It was found that a giant electrostrictive coefficient of 696 × 10−16 m2/V2 could be obtained at a high cooling rate of 0.75 °C/s to a temperature of TC + 4.5 °C due to the evolution of polar nano-regions, which is one order of magnitude larger than the previously reported value in KTN crystals. This strengthens the realization of replacing toxic lead-based electrostrictive materials with environmentally friendly KTN materials in real world applications.

Stable and high efficiency mixed-cation lead-based halide perovskite: A theoretical study

In this study, the stability and optoelectronic properties of DMA-doped α-MAPbI3 (DMA = CH3NH2CH3, MA = CH3NH3) have been explored in detail based on first-principles calculations. The results suggest that 12.5% DMA doping improves greatly the structural stability of α-MAPbI3, which indicates that α-MA0.875DMA0.125PbI3 may be stable at room temperature. The calculated band gap of α-MA0.875DMA0.125PbI3 is slightly larger than those of pure α-MAPbI3 and β-MAPbI3, which agrees well with the recent experimental value. In the visible light region, this material exhibits strong optical absorption coefficient. The predicted maximum power conversion efficiency of 20.46% is obtained for α-MA0.875DMA0.125PbI3. These results are useful for exploring stable and high efficiency lead-based perovskite materials in solar cells.

High-efficiency, flexibility and lead-free X-ray shielding multilayered polymer composites: layered structure design and shielding mechanism

To overcome the severe toxicity and blind absorption zone of conventional lead-based shielding materials for X-rays in the 70–90 keV range, the lead-free multilayered polymer composites were designed and fabricated. The effects of the direction of incidence of the X-rays and number of layers as well as layer thickness ratio of the (tungsten/ethylene-octene copolymer)/(bismuth/ethylene-octene copolymer) layered composites on their shielding efficiency were studied systematically. Compared to the traditional polymer blending, the multilayered polymer composites exhibited the improved photon attenuation. The multilayered polymer composites (layer thickness ratio was 3:7) with 6 layers had the best X-ray shielding ability. Moreover, the X-ray shielding provided by the multi-layered interfaces and the multiple complementary effect of the absorption within the multilayered structure were firstly proposed based on computer simulations. The multilayered structural design effectively weakened the probability of the X-ray penetration. Therefore, the X-ray shielding capability can be effectively enhanced through increasing number of layers and the synergistic effect of multi-layered interfaces. The experimental results of this study can serve as guidelines for the fabrication of flexibility, lead-free, lightweight and high-efficiency X-ray shielding materials.

The bandgap regulation and optical properties of alloyed Cs2NaSbX6 (X=Cl, Br, I) systems with first principle method

Lead-free halide double perovskite materials have the advantages of optical absorption efficiency, carrier mobility, adjustable bandgap, defect tolerance, wide variety of raw materials, low price, etc. which were used as many environmental substitutes for lead-based halide perovskite materials. In this work, we investigated the Cs2NaSbX6 (X = Cl, Br, I) systems with elements (K, In and Au) alloying and the photoelectric properties of the materials with the first principle method. The research results show that when the alloying concentration was 50%, all bandgaps of given double perovskite materials turned from indirect to direct bandgap. Especially, the alloying Cs2Na0.5K0.5SbI6's and the Cs2NaSb0.5In0.5I6's bandgaps were 1.92eVand 1.46eV, respectively. The energy values are well match within the range of applications as light absorbing materials. Optical properties show that the peak position of the absorption spectrum of the alloying elements of the Cs2NaSbX6 (X = Cl, Br, I) system is associated with the types of halogen elements at the X site, for X = Cl element, alloying elements to a certain proportion makes the absorption spectrum of the material red shift; for X = Br, There is no obvious change in the position of the peak of the absorption spectrum of the material; for X = I, after alloying elements to a certain proportion, the position of the peak of the absorption spectrum of the material has an obvious blueshifts. This work provides a reliable theoretical basis for the bandgap regulation of perovskite materials and a reference for the development of new non-toxic and environmentally friendly solar materials.

The Sol-hydrothermal Synthesis of Potassium Bismuth Titanate Nanoparticles

Aims: To propose a method of KBT synthesis at a lower temperature to solve the volatility of the components. Background: Lead-based perovskite materials have long been employed in electroceramic industries due to their excellent piezoelectric, ferroelectric, and dielectric properties. The high toxicity of lead, however, leads to the replacement of the use of lead-based perovskite in devices with more environmentally friendly materials. KBT powders are traditionally prepared by solid-state reaction through the calcinations of K2CO3, Bi2O3 and TiO2 at high temperature. The high-temperature calcination process leads to serious particle agglomeration, grain growth and small surface area, which decrease the activity of the KBT powder. Instability of the KBT ceramic according to the high volatility of its component ions at elevated temperatures was the main concern for the application feasibility. Objective: This work was aimed to present the simplified method called “sol-hydrothermal” for the synthesis of KBT nanoparticles. Microstructure and phase evolution of the nanoparticles were investigated in detail. Method: The sol-hydrothermal method was performed in potassium hydroxide (KOH) solution at 140-200°C for 2-24 h. Result: The result showed that increasing hydrothermal temperatures from 140°C to 200°C, the crystal structure was changed from pseudo-cubic to tetragonal. At 200°C, phase separation was observed. Suitable hydrothermal time was found to be between 6-12 h, above which phase separation was also observed. Increasing the KOH solution concentration from 10 to 12 or 15 and finally, 20 M gave rise to greater KBT peak intensity, suggesting a more complete crystallization process when the concentration was increased. Tetragonal KBT nanoparticles with c/a ratio of 1.0620 were obtained under the synthesis condition of 180°C for 12 h in 20 M KOH solution. Sinterability of the synthesized KBT nano-particles was further investigated by varying the sintering temperatures from 1000°C to 1080°C; the highest relative density of 97% was obtained in the sample sintered at 1050°C. However, at this sintering temperature and beyond, the sublimation of the K-containing component occurred as evident by the appearance of Bi2O3 and Bi4Ti3O12 phases. Conclusion: In summary, KBT nanoparticles have been successfully prepared by the simple solhydrothermal method in a basic solution at low temperatures. Synthesis temperature, time and KOH concentration were found to affect the powder characteristics greatly. Increasing synthesis temperature was found to affect the phase development while increasing synthesis time resulted in the development of crystallinity of the KBT powder obtained. Increasing KOH concentration from 10 M to 20 M gave rise to different particle growth and agglomeration degrees. The optimum synthesis conditions were at 180°C for 24 h in 10 M KOH solution. At this condition, KBT powder with a uniform particle size distribution and tetragonal structure could be obtained. The synthesis powder showed excellent sinterability. Sintering at only 1020°C for 2 h gave rise to fine grain ceramics with 95% relative density. However, as potassium was prone to sublime, increasing sintering temperature to 1050°C and beyond resulted in K-deficient phases. Sintering of the KBT should be done in K-saturating atmosphere to suppress this sublimation.