Screen-printed Paste Research Articles

22.56% total area efficiency of n-TOPCon solar cell with screen-printed Al paste

Screen-printing Ag paste on the rear side of the Tunnel Oxide Passivated Contact solar cells (TOPCon) is still the mainstream method to form electrodes. However, the high price of precious metals increases the cost of TOPCon cells. Al is a cheap and high-performance conductor, and its work function is compatible with the rear side of TOPCon cells. In this study, we used a UV pulse laser (355 nm, 10 ps) to ablate the rear side SiNx passivation layer of TOPCon cells and then printed Al paste with different weight percentages of silicon (Si-wt.%) on the phosphorus-doped polycrystalline silicon (n+-poly-Si) layer to reduce the cost. We investigated the damage mechanism of laser on SiOx/n+-poly-Si/SiNx passivation structure and the contact mechanism between Al paste and n+-poly-Si layer. The results show that the Voc of SiOx/n+-poly-Si/SiNx passivation structure reduced about 6–7 mV when the laser energy density was 0.431 J/cm2. We got the best electrical performance of TOPCon cells printed with Al paste (25 wt%-29 wt% silicon). The open-circuit voltage (Voc) and the conversion efficiency (Eff), have reached 663.60 mV and 22.56 % respectively. Although the efficiency was 9.40 % relative lower than that of TOPCon cells printed with Ag paste, but the cost of Al paste only accounted for 10 % of Ag paste. In the future, the highest Eff of TOPCon solar cells printed with Al paste on the rear side are expected to reach the commercial TOPCon based on Ag paste, which applies laser doping selective emitter technology (SE) and bifacial poly-Si passivation structure.

Insight of Effect of Silver Powders on Silver–Silicon Contacts of Crystalline Silicon Solar Cells through Analysis of Glass Structural Decay

Optimally designed silver–silicon (Ag–Si) contacts, based on silver (Ag) paste screen printing and the rapid sintering process, are widely utilized in mainstream crystalline silicon solar cells, enabling to reduce contact resistance and high photo‐conversion efficiency. Ag powder is the largest conductive component in Ag paste, but its impact on the formation of Ag–Si contacts lacks in‐depth research and comprehensive understanding. In this work, it is demonstrated that the oxygen adsorption capacity of silver powders affects the formation of Ag–Si contacts by enhancing the reactivity of Ag powders with glass frits, and has a significant effect on the performance of devices. The generation of Ag2O introduced by surface‐absorbed oxygen promotes the transformation of [TeO4] triangular bipyramidal into [TeO3] triangular pyramid, thus destroying the network structure of the glass frits. This structural decay accelerates the spreading of glass frits in the bulk, causing the glass frits to come into contact with SiNx layers earlier and facilitating the formation of the Ag–Si contacts. In this work, not only a complete picture of the interaction between Ag powder and glass frits but also a new direction is provided to optimize the Ag–Si contacts.

Influence of Flexible and Textile Substrates on Frequency-Selective Surfaces (FSS).

Frequency-selective surfaces (FSS) are two-dimensional geometric structures made of conductive materials that selectively transmit or reflect electromagnetic waves. In this paper, flexible FSS made on textile and film substrates is presented and compared to show the effect of the texture associated with the type of substrate on the shielding properties. Three geometries of patterns of squares in the border, inversion of squares in the border, and circles with a border were used, and the patterns were made by the silver paste screen printing technique. Microscopic analysis (SEM and optical) was performed to determine the degree of substrate coverage and the actual geometry of the pattern. The resistance per square of the obtained patterns was about 50 mΩ/□. The shielding properties of FSS were simulated in Comsol Multiphysics 6.2 software and then measured by the antenna method. Selective textile filters were obtained, depending on the pattern used, with one or two modals with a transmission attenuation of about 15 dB. The paper analyzes the effect of the substrate and the screen printing technique used on the shielding properties of the flexible FSS.

Metal-Complex Inks for Lower Cost and Improved Passivation for Silicon Photovoltaic Metallization

This contribution introduces the silicon PV community to screen-printable metal-complex inks that potentially will reduce Ag usage in Si PV metallization to one-quarter and costs to one-third that of traditional particle-based pastes while also improving passivation. Metal-complex inks are formulated using a Tollen’s reaction to produce inks with a high percentage of diamminesilver (I) cations (22 wt %) in a solution of acetate and formate anions. When printed and dried, labile ammonia ligands evaporate, leaving behind silver cations which, when reduced by formate anions and acetic acid, plate out silver and silver acetate. When annealed to just 300 °C a dense metallic silver film forms with excellent conductivity, and adhesion to silicon. When compared to traditional particle-based screen-printing pastes, the metal-complex inks are much denser, have higher conductivity, use less Ag, and are a fraction of the cost. Importantly, the inks anneal from 90 – 450 °C allowing for improved passivation schemes compared with fired SiNx. This contribution highlights first experiments on the improved passivation of metallized poly-Si/SiO2 passivated contacts using metal-complex Ag inks.

Optimization of the application of cationic agent in the screen printing paste with reactive dye on cotton substrate

Optimization of the application of cationic agent in the screen printing paste with reactive dye on cotton substrate

Aging tests of mini-modules with copper-plated heterojunction solar cells and pattern-transfer-printing of copper paste

Abstract: Mini-module aging tests with differently interconnected heterojunction solar cells having industrially viable copper metallization are presented. The plating process comprises 3 steps: firstly, screen printing of a seed-grid layout using a copper-based paste, followed by deposition of a dielectric layer over the entire wafer surface, and finally, selective copper electrodeposition on grid positions. Modules with Smartwire interconnection, fabricated with M6 half-cells, are stable in extended TC and PID tests. DH degradation is at 5% after 2700 h (glass-glass modules without edge sealing). Shingle modules, realized in collaboration with CEA INES and AMAT, exhibit notably higher fill factor compared to reference modules with screen-printed silver paste. This improvement is attributed to the superior line conductivity achieved with plated copper. TC stability of shingle modules is very good, whereas after 2000 h damp-heat aging more than 2% loss in fill factor is observed. Using pattern-transfer-printing technology narrow, high aspect-ratio lines have been obtained: with a seed-grid of pure copper paste, reinforced with electrodeposited copper. Line dimensions and line resistance as well as first cell results are presented.

Penyuluhan dan Pelatihan Keterampilan Sablon Pigment Pasta Manual Di Kelurahan Kersanegara Kota Tasikmalaya

Background: Community service through counseling and training in manual Pigment Paste screen printing skills in creating business opportunities in Kersanegara Village, Cibeureum District, Tasikmalaya City. This activity aims to accommodate young people in Kersanegara Village, Tasikmalaya City by providing manual screen printing training. Method: The partners for this activity are youth in the Kersanegara area of ​​Tasikmalaya City. The number of participants is five people. This counseling and training are held where the counseling and training is carried out in Kersanegara Village, Tasikmalaya City, with 5 participants made into one business group, and data collection is carried out by involving Village officials. The results achieved from this community service activity were the forming of a manual screen printing business group and collaboration between the screen printing business group and other MSME partners. Result: Screen printing training has been well implemented. Apart from that, the participants were given knowledge regarding managerial improvements, such as providing knowledge and skills for preparing financial reports, innovation, and differentiation designs, which has been realized. Conclusion: Formation of a manual screen printing business group, collaboration between screen printing business groups with other MSME partners. An indicator of the success of this program is that the business group has started receiving orders, even though the quantities are still small.

The concentration factor on the mixture of Ag paste and H3PO4 solution as a dopant paste for contact formation in silicon solar cells

Screen printing dopant is a new technique to create emitter regions on solar cells. On top of the emitter region, there will be screen-printed metallic contacts that are commonly used silver as front contact. Both processes are performed in separate procedure which requires two different diffusion process involving a high-temperature process. Silver makes good ohmic contact on both light and heavily doped. A solution is proposed by applying a single step of screen printing and annealing process of Ag and phosphorus acid. Simultaneous annealing of Al, Ag, Ag/P screen-printed pastes form diodes with and without heavily doped phosphorous layers under Ag contacts on n-type and p-type silicon wafers by annealing at a constant temperature of 900℃ while varying annealing time from 10-40 seconds at a 10-second interval. The cross-section image of 5% and 10% of Ag/P was measured by using FESEM with EDX report has identified the presence of phosphorus in the Ag/P paste. Dark IV shows an ohmic contact for both p- and n-type. The ability to form the Ag/P paste in the screen-printing process makes it amenable to use as a self-dopant paste process in solar cells.

Understanding and mitigating resistive losses in fired passivating contacts: role of the interfaces and optimization of the thermal budget

This work presents a study of p-type passivating contacts based on SiCx formed via a rapid thermal processing (RTP) step, using conditions compatible with the firing used to sinter screen-printed metallization pastes in industry. The contributions of the two interfaces (wafer/contact and contact/metal) to the contact resistivity are first decorrelated, identifying tunnelling at the wafer interface as the main contribution. We then investigate the influence of the active dopant concentration on the contact resistivity and the SiCx sheet resistance and propose strategies to reduce both resistances by increasing the thermal budget applied during RTP. Lastly, we discuss potentials and limitations of implementing the investigated stacks as rear side contacts of p-type devices with localized metallization. We demonstrate that increasing the thermal budget during RTP can effectively mitigate resistive losses and enhance contact performance and we show that an oxide layer that can withstand high thermal budgets is the key factor for obtaining simultaneously high passivation quality and good electrical properties. We investigate three different oxide types grown by HNO3 immersion, UV-O3 exposure and N2O plasma oxidation. The latter is demonstrated to be a promising candidate for an application in devices fabricated with high RTP thermal budget.

Reduced global warming potential in carbon-based perovskite solar modules: Cradle-to-gate life cycle analysis

Given the superior stability, technologically developed and cost effectiveness of carbon-based perovskite solar cells over conventional metallic electrode-based architectures, this work investigates the environmental performance of two industrial front-runners architectures i.e., high temperature processed carbon-based perovskite solar modules (CPSMs) and low temperature processed CPSMs using cradle-to-gate Life Cycle Assessment analysis assuming a manufacturing plant in India. According to the study, most of the impacts are due to energy consumption in the annealing and screen print paste process used in ETL, perovskite, HTL and cathode layer for both the architectures. Material selection for the perovskite and other layers has a significant environmental impact on both architectures. Compared to low temperature processed architecture, high temperature processed CPSMs have a greater environmental impact. For a five-year lifetime, the global warming potential (GWP) values for high temperature and low temperature processed CPSMs are 0.180 kg CO2-eq and 0.126 kg CO2-eq, respectively, which are marginally higher than those indicated for commercially available silicon solar cells. Thus, a sensitivity analysis was performed to determine the minimum lifetime required to compete with GWP values comparable to commercial PVs. High and low temperature processed CPSM needed 16 and 11 years of lifetime, respectively, to match silicon's 25 years of lifetime. On the other hand, the study finds the human toxicity contribution by mono-silicon is extremely high compared to the two CPSM architectures because of the contribution by electricity (44.01%) and use of heavy metals such as copper (16.83%) and steel (11.52%).

Screen-printed Sn-doped TiO2 nanoparticles for photocatalytic dye removal from wastewater: A technological perspective

TiO2 is widely used as a photocatalyst with a wide band gap, which limited its application. Ion doping and formulating a high-quality screen-printing paste enhance its features. However, the printability of objects for advanced application seems essential nowadays. In this research, the Sn-doped TiO2 nanoparticles were prepared through a sol-gel method followed by calcination at various temperatures of 450 °C, 550 °C, 650 °C, 750 °C, and 850 °C. Screen-printing pastes were prepared with 18 wt% of the synthesized Sn-doped TiO2 nanoparticles to evaluate photocatalytic activity. Finally, the prepared paste with optimum nanoparticle concentration was screen printed onto the microscope glass slides at various printing times (1, 3, and 5 runs) and annealed at 500 °C temperature to investigate the thickness of printed Sn-doped TiO2 nanoparticles effect. The photocatalytic activity and crystal structure of nano Sn-doped-TiO2 were characterized using photoluminescence (PL) spectroscopy and X-ray diffraction (XRD). Transmission electron microscopy (TEM) and scanning electron microscope (SEM) analyses were conducted to investigate the size and morphology of the prepared nanoparticles, respectively. The highest photocatalytic activity for the degradation of methylene blue was obtained at the calcination temperature of 450 °C.

In-situ X-ray diffraction analysis of SiGe liquid phase growth on Si using Al–Ge paste

We performed in-situ two-dimensional X-ray diffraction measurements during a silicon-germanium (SiGe) layer formation process to analyze the liquid-phase epitaxial growth of a SiGe layer on silicon (Si) substrate by a simple method of aluminum-germanium (Al–Ge) paste screen-printing and annealing. The aluminum (Al) and germanium (Ge) from the Al–Ge paste were found to be in the liquid phase starting around 540 °C for the Al–Ge paste containing Al and Ge powders, while it starts around 430 °C for the one containing Al–Ge alloy powder. During the cooling process from the peak temperature of 900 °C down to 430 °C, a SiGe layer was epitaxially grown in the same orientation as the Si substrate. Around 430 °C, the remaining material in the liquid phase formed during the temperature increase solidified and the reaction was terminated. The XRD results suggest that most of the Al in the liquid phase exists as liquid phase from the peak temperature down to 430 °C. The Al liquid phase mediates the melting of Si and Ge, and the Si substrate functions both as a Si source, and as a seed crystal for the growth of the SiGe layer. Both samples show that the Ge concentration is sharply increased in the SiGe layer to around 13 at% at the interface and retains a uniform concentration distribution up to the Al paste matrix/SiGe interface. The change in crystallinity during the liquid phase growth indicates that the properties of the SiGe layer formed by this method can be controlled by adjusting the composition of the Al–Ge paste and the annealing temperature profile.

Multifunctional screen-printed films using polymer nanocomposite based on PPy/TiO2: conductive, photocatalytic, self-cleaning and antibacterial functionalities

In this work, two electrically conductive samples based on polypyrrole (PPy) and (PPy/TiO2) were synthesized via mini-emulsion polymerization. Synthesized samples were used as functional fillers to formulate two different screen-printing pastes (pastes A and B) to obtain the multi-purpose printed films with excellent properties, including electrical conductivity, antibacterial, photocatalytic activity, and self-cleaning. The surface tension, pH, and conductivity measurements validated the acceptable features of the produced pastes. Because of the shear-thinning behavior and viscosity buildup properties of the produced pastes, rheological investigations confirmed their potential for screen-printing. According to I–V test results, the optimum sintering temperature was chosen as a function of electrical conductivity, and the properties of the printed patterns were investigated by varying the printing sequences as 3, 6, and 9 times and sintered at the optimum temperature (90 °C). The contact angle of water on the optimum sample printed by Paste B was ca. 127° and relatively higher than the counterpart printed by Paste A which verified the superiority of the self-cleaning properties of the printed films with latter paste over the former. The photocatalytic studies concerning the degradation of methylene blue showed that the removal percentage of ca. 63% was achieved within the first 90 min of performing the test under UV light. The photocatalytic printed film was addressed the issue of filtering the unused suspension of nanoparticles, which made it difficult to remove the particles from the treated wastewater, in terms of sustainability. The fabricated patterns using Paste B exhibited improved properties, including electrical conductivity, antibacterial and photocatalytic activity.Graphical abstract

Quantum dots printing paste for display backlights: Preparation, characterization, and applications

AbstractQuantum dots (QDs) are one kind of photoluminescent materials with excellent properties, such as adjustable spectrum, narrow full width at half maximum (FWHM), and high color gamut. In this paper, a photoluminescent QDs printing paste suitable for light guide dots array applied in the backlight for liquid crystal display (LCD) was presented. The QDs printing paste was first prepared and characterized with different kinds of solvents. Then, triphenyl phosphite (TPP), a kind of antioxygen, was added into the QDs printing paste to improve the stability of the QDs printing paste. Finally, a QDs light guide plate (LGP) was fabricated by screen printing with QDs printing paste added with silicon dioxide (SiO2) light scattering particles. The color gamut of QDs LGP arrived 131.6%NTSC due to light scattering interaction between blue LED, red QDs, green QDs, and SiO2 particles. The results showed that the QDs‐chloroform printing paste had uniform light output and the highest photoluminescent peak intensity. Therefore, the composite screen printing paste has wide application prospects in the backlight of LCD, with the advantages of simple process, high production efficiency, and low cost.

The Influence of the Matrix Selection and the Unification Process on the Key Parameters of the Conductive Graphene Layers on a Flexible Substrate.

Screen-printed graphene layers on flexible substrates are one of the most advanced printed electronics developments of recent years. Obtaining thin, flexible, highly conductive components, whose applications are increasingly directed towards biomedical engineering and even medicine, requires an in-depth understanding of the correct choice of materials and procedures. Our work was aimed at investigating the influence of homogenisation in the triple rolling process over pastes dedicated to the screen printing technology, on their rheological parameters and the properties of the prints. The effect of selecting a suitable polymer matrix and different packing of graphene flakes was evaluated. Several studies were carried out, which can provide an excellent knowledge base in the context of graphene screen-printing pastes. Paste rheology, printability, path thickness, sheet resistance and adhesion to the substrate were investigated. Selected layers were also subjected to SEM imaging.

Visible-light-driven super-active Sn and GO single- and Sn/Cu Co-doped nanophotocatalysts for phenol degradation: Thin-film printability, thermal stability, and cytotoxicity assay

Sn- and graphene oxide (GO) single-doped and Sn/Cu co-doped titanium dioxide (TiO2) nanoparticles were synthesized as printed-layer nano-photocatalysts for degradation of phenol under visible-light. The doped TiO2 nanoparticles (Sn-doped-TiO2, Cu/Sn-doped-TiO2, and GO-doped-TiO2) were synthesized via sol–gel method and calcinated at a temperature of 450 °C. X-ray diffraction (XRD), UV–Visible DRS analysis, Raman analyses, and Energy-dispersive X-ray spectroscopy (EDXS) were utilized to evaluate the crystalline structure and photocatalytic activities of doped-TiO2 nanoparticles. Different screen-printing pastes were separately formulated with 26% w/w doped-TiO2 nanoparticles (Paste1-to-Paste3) for printing onto microscope glass slides. Photocatalytic printed film was sustainable filter for unused suspension of nanoparticles in wastewater. The printed pasts were sintered at varying temperatures (100–500 °C), then three-layer printed nanoparticles sintered at 500 °C examined for photocatalysis. Photocatalytic activity of single-layer-printed GO-doped-TiO2 nanoparticles was extraordinary (80% degradation of 10 ppm phenol solution). Hydroquinone, catechol, benzoquinone and acetic acid were observed to be produced at different concentrations over different time intervals as a result of phenol degradation for single-layer-printed GO-doped-TiO2 nanoparticles sintered at 500 °C. Bandgap of GO-doped-TiO2 nanoparticles was 2 eV, meaningfully lower than anatase TiO2 (3.2 eV). The cytotoxicity assay applied for normal and cancer cells demonstrated cytocompatibility besides photodegradability. This novel process is a targeted, clean, cost-effective and on-demand approach, taking a big step toward decontamination of the environmental pollution.

Recent advances in the modification of electrodes for trace metal analysis: a review.

This review paper summarizes the research published in the last five years on using different compounds and/or materials as modifiers for electrodes employed in trace heavy metal analysis. The main groups of modifiers are identified, and their single or combined application on the surface of the electrodes is discussed. Nanomaterials, film-forming substances, and polymers are among the most used compounds employed mainly in the modification of glassy carbon, screen-printed, and carbon paste electrodes. Composites composed of several compounds and/or materials have also found growing interest in the development of modified electrodes. Environmentally friendly substances and natural products (mainly biopolymers and plant extracts) have continued to be included in the modification of electrodes for trace heavy metal analysis. The main analytical performance parameters of the modified electrodes as well as possible interferences affecting the determination of the target analytes, are discussed. Finally, a critical evaluation of the main findings from these studies and an outlook discussing possible improvements in this area of research are presented.

Model for contact formation of novel TeO2 containing Pb-free silver paste on n+ and p+ doped crystalline silicon

Silver (Ag) pastes are widely used in the global market for most solar cell architectures. Thereby, lead (Pb) is no longer wanted in productions for environmental reasons. In this work, a model for the contact formation between Pb-free, tellurium oxide (TeO2) containing screen-printable Ag pastes and silicon is presented. It is shown that Te plays a key role in this model. Te is not only an important part in etching the surface passivation layers with TeO2 dissolving the dielectric layer but also for a formation of the contacts with Te forming a compound consisting of Ag2Te. Using EDX mapping, local contact regions can be examined and interpreted for contact formation. The used paste system enables far more flexible paste mixturing leading to a novel developed commercial paste which is on a par with other pastes used in industry concerning the resulting contact properties. This is also demonstrated in this work by the very low contact resistivity of less than 1 mΩcm2 over a wide range of firing peak temperatures. It is additionally shown that good resistivities can be achieved on both n+- and p+-doped regions.

All-Solid State Potentiometric Sensors for Desvenlafaxine Detection Using Biomimetic Imprinted Polymers as Recognition Receptors.

Using single-walled carbon nanotubes (SWCNTs) as an ion-to-electron transducer, a novel disposable all-solid-state desvenlafaxine-selective electrode based on a screen-printed carbon paste electrode was created. SWCNTs were put onto the carbon-paste electrode area, which was protected by a poly (vinyl chloride) (PVC) membrane with a desvenlafaxine-imprinted polymer serving as a recognition receptor. Electrochemical impedance spectroscopy and chronopotentiometric techniques were used to examine the electrochemical characteristics of the SWCNTs/PVC coating on the carbon screen-printed electrode. The electrode displayed a 57.2 ± 0.8 mV/decade near-Nernstian slope with a 2.0 × 10-6 M detection limit. In 10 mM phosphate buffer, pH 6, the ODV-selective electrodes displayed a quick reaction (5 s) and outstanding stability, repeatability, and reproducibility. The usefulness of electrodes was demonstrated in samples of ODV-containing pharmaceutical products and human urine. These electrodes have the potential to be mass produced and employed as disposable sensors for on-site testing, since they are quick, practical, and inexpensive.

Photocatalytic Properties of TiO2 Electrodes on Stainless Steel Substrate Using Optimized TiO2 Pastes for Screen Printing

Solar cells and panels are one of the applications by converting solar energy into electrical energy. However, there exist environmental impacts such as deforestation, microclimate change, soil quality deterioration and migration of wildlife animals when a large amount of land areas are used for solar power plants. One of the solutions to those issues is to build floating solar panels in dams and lakes. We still need to apply large water areas, i.e., oceanic areas for those floating solar cells. Our research group has been studying floating solar cells that are compatible and have the potential to be used in marine environments. This solar cell is made of titanium dioxide photoanode and copper oxides photocathode with seawater electrolyte. Titanium dioxide (TiO2) has been studied for its photocatalytic properties. In this study, the photocatalytic properties of screen printed TiO2 electrodes on stainless steel substrate prepared from different pastes of TiO2 were examined and analysed.Type 329J4L stainless steel with duplex phase structure (ferritic + austenitic) was used as a substrate for TiO2 electrode. At first, the surface of the substrate was polished by sandpaper of 60 grade to form a grid pattern on it. The substrate was then cleaned by acetone in ultrasonic cleaner for 10 minutes and rinsed with distilled water. After that, the substrate was treated with passivation treatment. In this treatment, the substrate was placed in 10 % nitric acid (HNO3) solution at 60 ºC for 30 minutes and then rinsed with distilled water. After passivation treatment, the substrate was printed with TiO2 paste and heat treated at 150 ºC for 60 minutes to form the first layer of TiO2 film on the substrate. The second layer of TiO2 film was formed by screen printing of TiO2 paste followed by heat treatment at 550 ºC for 30 minutes. Finally, the electrode was solder welded and coated with epoxy resin to get ready for the measurement. Different TiO2 pastes were prepared and used for printing on the substrate. The first one was using the purchased TiO2 paste (SP-100 Showa Denko, Japan). The other ones were prepared from TiO2 powder (Sigma-Aldrich). Those pastes were prepared using the certain ratios of TiO2 powder, nitric acid, acetic acid, tritonX-100, and polyethylene glycol.The potential and polarization measurement of the electrodes were carried out in artificial seawater. The irradiation measurement was conducted using a xenon lamp (150 W) with a calibrated wavelength range of 250 nm to 800 nm and output irradiation intensity of 10.5 mW/cm2. Saturated calomel electrode (SCE) was used as a reference electrode and the potentio-galvanostat (SDPS-511U, Japan) was used as the measuring device. Figure 1 shows the potential values over a 2 -hour irradiation testing of two TiO2 electrodes prepared from two different pastes. The optimized TiO2 paste showed higher photopotential performance over time than the merchandized one. The surface and microstructures of the electrodes before and after the measurement were examined by Scanning Electron Microscope (SEM) and the pastes were investigated by Thermogravimetry Differential Thermal Analysis (TG-DTA) and X-ray powder diffraction (XRD). The results are planned to be presented in the upcoming ECS conference meeting. Figure 1