Fabrication Of Cells Research Articles

Optimization strategies for metallization in n-type crystalline silicon TOPCon solar cells: Pathways to elevated fill factor and enhanced efficiency

In advancing photovoltaic technology, optimizing the metallization process is crucial for balancing electrical conductivity and optical performance in solar cell fabrication. This process directly impacts the efficiency and quality of solar cells, traditionally measured by the fill factor (FF). Historically, efforts have focused on evolving metal contacts to reduce optical shading and series resistance, which degrade solar cell efficiency. Our study enhances n-type Tunnel Oxide Passivated Contact (n-TOPCon) solar cells by optimizing screen-printing metallization, particularly by examining the effects of squeegee speeds. Employing a mix of experimental and analytical methodologies, we aimed to identify optimal conditions that improve electrical and optical performance, thereby elevating cell efficiency. Our findings indicate that a squeegee speed of 170 mm/s substantially boosts solar cell performance, evidenced by a current density (Jsc) of 38.96 mA/cm2, open-circuit voltage (Voc) of 684.29 mV, fill factor (FF) of 78.77 %, and a power conversion efficiency (PCE) of 21.00 %. Further, dark I–V measurements confirmed a shunt resistance (Rsh) of 6.25 × 106 Ω and a reduced series resistance (Rs) of 6.48 Ω, underscoring the significance of precise metallization in reducing resistive losses and enhancing efficiency. Future research will explore innovative materials and cutting-edge printing techniques beyond squeegee speed adjustments. The potential incorporation of nanomaterials and conducting polymers aims to refine the metallization process further, promising to push the boundaries of efficiency and cost-effectiveness. This progression is essential for advancing n-TOPCon solar cell development, setting new industry standards, and propelling the sustainable energy movement.

Ecodesign of Kesterite Nanoparticles for Thin Film Photovoltaics at Laboratory Scale.

This manuscript investigates the efficient synthesis of copper zinc tin sulfide (CZTS) nanoparticles for CZTS thin film solar cell applications with a primary focus on environmental sustainability. Underpinning the investigation is an initial life-cycle assessment (LCA) analysis. This LCA analysis is conducted to evaluate the environmental impact of different synthesis volumes, providing crucial insights into the sustainability of the synthesis process by considering the flows of material and energy associated with the process. Life-cycle assessment results demonstrate that significant reductions to the environmental impact can be made by increasing the synthesis volume of CZTS nanoparticle ink. Using a 5-fold increase in volume can reduce all 11 investigated environmental impacts by up to 35.6%, six of these impacts demonstrating reductions >10% and the amount of global warming potential is reduced by 21.4%. Motivated by the LCA results, COMSOL simulations are employed to understand the fluid flow patterns in large-scale fabrication. Various sizes and speeds of stirrer bars are investigated in these simulations, and it is determined that a 50 mm stir bar at 200 rpm represents the optimal configuration for the synthesis process in a 500 mL flask. Subsequently, large-batch CZTS nanoparticle inks are synthesized using these parameters and compared to small-batch samples. The light absorbers are characterized using Raman spectroscopy and X-ray diffraction, confirming favorable properties with close-to-ideal elemental ratios in large-batch synthesis. Finally, solar cell devices fabricated utilizing CZTSSe absorbers from the large volume synthesis process demonstrate comparable performance to those fabricated using small-batch synthesis, with uniform power conversion efficiencies of around 5% across the substrate. This study highlights the potential of large-volume CZTS nanoparticle synthesis for efficient and environmentally friendly CZTS solar cell fabrication, contributing to the advancement of sustainable renewable energy technologies.

Study of defect density of copper vacancies in chalcogenide CuSbS2, CuSbSe2, CuBiS2, and CuBiSe2 heterojunction thin-film solar cells.

In the past decade, a new family of ternary chalcogenide absorber (TCA) materials MIMIIX2 (where MI = Cu, Ag, Pb; MII = Sb, Bi, In; and X = S, Se, Te) have been studied. The copper family of ternary chalcogenide CuSbS2 CuSbSe2 CuBiS2, and CuBiSe2 is an amazing absorber material for thin-film solar cells because of their suitable band gap, high absorption coefficient and inexpensive, nontoxic, environment friendly and sustainable nature. In the presented work, first time simulated defect density of copper vacancies in CuSbS2 (CAS), CuSbSe2 (CASe), CuBiS2 (CBS) and CuBiSe2 (CBSe) has based heterojunction thin-film solar cells (HJTFSCs) with buffer CdS, intrinsic i-ZnO, window ZnO: Al and back contact Mo and set the cell scheming ZnO: Al/i-ZnO/n-CdS/p-TCA/Mo using SCAPS 1D. Major focus of this paper is on the influence of copper vacancies defect density that impact on the performance of ternary chalcogenide with various parameters of solar cells, i.e. short-circuit current density (Jsc), open-circuit voltage (Voc), form factor (FF) and efficiency (η). The cell parameter set at constant temperature 300K, thickness 2.5μm, carrier density 5 × 1016cm-3, front internal transmission coefficient 1 and illumination intensity 100 mW/cm2 with AM1.5 sun light. This study clarifies the potential benefits to utilizing of ternary chalcogenide compounds as absorber material for solar cell fabrication.

Effect of Substitutional Metallic Impurities on the Optical Absorption Properties of TiO2.

(TiO2) is both a natural and artificial compound that is transparent under visible and near-infrared light. However, it could be prepared with other metals, substituting for Ti, thus changing its properties. In this article, we present density functional theory calculations for Ti(1-x)AxO2, where A stands for any of the eight following neutral substitutional impurities, Fe, Ni, Co, Pd, Pt, Cu, Ag and Au, based on the rutile structure of pristine TiO2. We use a fully unconstrained version of the density functional method with generalized gradient approximation plus the U exchange and correlation, as implemented in the Quantum Espresso free distribution. Within the limitations of a finite-size cell approximation, we report the band structure, energy gaps and absorption spectrum for all these cases. Rather than stressing precise values, we report on two general features: the location of the impurity levels and the general trends of the optical properties in the eight different systems. Our results show that all these substitutional atoms lead to the presence of electronic levels within the pristine gap, and that all of them produce absorptions in the visible and near-infrared ranges of electromagnetic radiation. Such results make these systems interesting for the fabrication of solar cells. Considering the variety of results, Ni and Ag are apparently the most promising substitutional impurities with which to achieve better performance in capturing the solar radiation on the planet's surface.

Controlling Water for Enhanced Homogeneities in Perovskite Solar Cells with Remarkable Reproducibility

AbstractTwo‐step sequential deposition of perovskite films is proven efficient and compatible with large‐scale production. Nevertheless, its critically regulated environmental humidity often remains a burden, hindering its applications in reproducible fabrication of perovskite solar cells (PSCs). Herein, by introducing a water ethyl acetate (W‐EA) solution treatment before annealing, improved perovskite crystallinity and homogeneity in FA0.95‐xMAxCs0.05PbI3 films without additional composition regulation is achieved. In situ Grazing‐incidence Wide‐angle X‐ray Scattering experiments highlighted accelerated crystallization kinetics in W‐EA‐treated films, leading to high‐quality perovskite formation. PSCs based on this method reached an optimal power conversion efficiency of 25.01% and demonstrated enhanced moisture resistance, retaining 88% efficiency after 1000 h in ambient conditions. This W‐EA treatment simplifies the fabrication process, greatly reducing the need for controlled humidity, and offers insights into the role of water in perovskite film crystallization, with significant implications to produce high‐performance PSCs.

Revealing the dynamic interface evolutions of electrochemical pre-lithiated graphite electrodes in practical workplace atmospheres

The electrochemical pre-lithiation (EC-PrLi) method using half-cell configuration exhibits great potential in constructing a uniform and stable solid electrolyte interface (SEI) in lithium-ion batteries (LIBs). The exposure procedures for EC-PrLi electrodes are inevitable during electrode transfer and cell fabrication, the SEI structure and stability of pre-lithiated electrodes are significantly affected for the high reactivity of SEI in ambient air. Hence, the stability of pre-lithiated electrodes is one of the most significant indexes reflecting the possibility for large-scale applications. Here, graphite electrodes are chosen for EC-PrLi, revealing for the first time the dynamic interface evolution of pre-lithiated graphite electrodes exposed to practical environments (glove box:GB and dry room:DR). The SEI of the lithiated electrode (D-12) exposed to a more realistic environment (DR) evolves into unstable and thin (∼1.5 nm) poor-LiOH SEI. The electrochemical performance changes of lithiated electrodes exposed to different conditions are being revealed. The lithiated graphite electrode (D-12) exhibits poor rate characteristics (314.6 mAh g−1 at 0.05 C and 22.8 mAh g−1 at 1.0 C) and cycling stability (capacity retention rate of 81.3 %). This work reveals the dynamic interface evolution of EC-PrLi graphite electrodes in practical environments, providing guidance for the broader application of pre-lithiation technology in practical.

Hydrothermal and electrochemical synthesis of Fe2O3 and ZnFe2O4/Fe2O3 photoanodes for photoelectrochemical applications: An experimental and theoretical study

Hematite (Fe2O3) is commonly utilized in the fabrication of photoelectrochemical cells for water-splitting reaction. However, its relatively low efficiency has highlighted the necessity for enhancements in Fe2O3-based photoanodes. In addressing this issue, this study implemented the addition of ZnFe2O4. The pure Fe2O3 was synthesized onto a Fluorine-doped Tin Oxide coated glass by the hydrothermal process, followed by the synthesis of various ZnFe2O4/Fe2O3 heterostructures using electrochemical deposition techniques. The thin film’s composition, surface morphology, and chemical species of the products were analyzed using X-ray Diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, and X-ray Photoelectron Spectroscopy, respectively. The performance of the Fe2O3-based photoanode was compared to that of various ZnFe2O4/Fe2O3 photoanodes through photoelectrochemical studies. Results indicated that a 50 s electrochemical deposition of ZnFe2O4 on Fe2O3 yielded the highest photoconversion efficiency. Additionally, Density Functional Theory was employed to investigate the electron energy level of ZnFe2O4, revealing alignment with the properties of Fe2O3. Theoretical analysis showed that the Fermi energy of ZnFe2O4 exceeded that of Fe2O3, suggesting a preferable direction for electron transfer from ZnFe2O4 to Fe2O3 which was in consistent to the Mott-Schottky analysis. The performance of the overall ZnFe2O4/Fe2O3 heterostructure photoanodes demonstrated greater efficiency compared to pristine Fe2O3.

A quasi-static time-series approach to assess the impact of high distributed energy resources penetration on transmission system expansion planning

Due to advancements in solar cell fabrication and inverter-based technology, as well as decreasing acquisition costs, solar distributed generation systems have emerged as a promising renewable source. Furthermore, electrification of the transportation system is an alternative promoted by many governments to mitigate the dependency on fossil fuels and achieve the goals of decarbonizing the economy. However, interconnecting a large quantity of distributed energy resources (DERs) to the power system reveals technical problems affecting the entire system. Planning coordinators and grid operators need to understand the full-spectrum impact of DERs on the power system to ensure secure and reliable grid planning and operations. The operation of a Hydro-Québec transmission system planned for 2030 is simulated in quasi-static time series mode with a massive integration of 1 million of electric vehicles and 1000 – 3000 MW of distributed photovoltaics. This paper provided findings on assessment of high DER penetrations impacts on the transmission system in terms of voltage control, mitigation means used, MVAR availability and consumption margin, generating unit optimal operation, and switching actions of several equipment.

Efficient and Stable Air-Processed Organic Solar Cells Enabled by an Antioxidant Additive.

Current high-efficiency organic solar cells (OSCs) are generally fabricated in an inert atmosphere that limits their real-world scalable manufacturing, while the efficiencies of air-processed OSCs lag far behind. The impacts of ambient factors on solar cell fabrication remain unclear. In this work, the effects of ambient factors on cell fabrication are systematically investigated, and it is unveiled that the oxidation and doping of organic light absorbers are the dominant reasons causing cell degradation when fabricated in air. To address this issue, a new strategy for fabricating high-performance air-processed OSCs by introducing an antioxidant additive (4-bromophenylhydrazine, BPH) into the precursor solutions, is developed. BPH can effectively inhibit oxygen infiltration from the ambient to the photoactive layer and suppress trap formation caused by oxidation. Compared with conventional air-processed OSCs, this strategy remarkably increases the cell power conversion efficiency (PCE) from 16.7% to 19.3% (independently certified as 19.2%), representing the top value of air-processed OSCs. Furthermore, BPH significantly improves the operational stability of the cells in air by two times with a T80 lifetime of over 500 h. This study highlights the potential of using antioxidant additives to fabricate high-efficiency and stable OSCs in air, significantly promoting the industrialization of OSCs.

Mixed etching-oxidation process to enhance the performance of spin-transfer torque MRAM for high-performance computing

Spin-transfer torque magnetic random access memory (MRAM) devices have considerable potential for high-performance computing applications; however, progress in this field has been hindered by difficulties in etching the magnetic tunnel junction (MTJ). One notable issue is electrical shorting caused by the accumulation of etching by-products on MTJ surfaces. Attempts to resolve these issues led to the development of step-MTJs, in which etching does not proceed beyond the MgO barrier; however, the resulting devices suffer from poor scalability and unpredictable shunting paths due to asymmetric electrode structures. This paper outlines the fabrication of pillar-shaped MTJs via a four-step etching process involving reactive-ion etching, ion-beam etching, oxygen exposure, and ion-trimming. The respective steps can be cross-tuned to optimize the shape of the pillars, prevent sidewall redeposition, and remove undesired shunting paths in order to enhance MTJ performance. In experiments, the proposed pillar-MTJs outperformed step-MTJs in key metrics, including tunneling magnetoresistance, coercivity, and switching efficiency. The proposed pillar-MTJs also enable the fabrication of MRAM cells with smaller cell sizes than spin–orbit torque devices and require no external field differing from voltage-controlled magnetic anisotropy devices.

Quality Implications of Foreign Metallic Particles in the Membrane Electrode Assembly of a Fuel Cell

Foreign metallic particles unintentionally trapped within the membrane electrode assembly (MEA) may adversely affect quality and yield of high-volume fuel cell production, for instance by damaging the membrane or releasing metallic cation contaminants. The present work aims to understand the impacts of 55 ± 5 μm Fe and SS316L metallic particles present at the membrane - cathode catalyst layer (CCL) interface during fuel cell fabrication, conditioning, and diagnostics. In-situ X-ray computed tomography imaging of particle-laden MEAs within a customized small-scale fuel cell fixture reveals that Fe particles undergo complete dissolution within the first air starve cycle of the conditioning phase. After dissolution, legacy particles are observed to incur considerable damage within the MEA, including void spaces at the membrane-CCL interface, membrane thinning, CCL cracks, and membrane rupture. In stark contrast, the SS316L particles feature negligible dissolution during fuel cell conditioning and diagnostics and remain largely intact, merely causing membrane-CCL delamination in their vicinity. Post-operation chemical analysis by laser ablation inductively coupled plasma mass spectrometry indicates Fe ion concentrations in the range of 800–950 ppm and 10–25 ppm for the Fe and SS316L laden MEAs, respectively, which correlates to visual observations of particle dissolution and slight reductions in fuel cell performance.

Fabrication of a New Dye-Sensitized Solar Cell Using CuO/TiO2 Nanocomposite Synthesized via an Electrochemical Technique

Various standard methods have previously been used for the synthesis of nanoparticles that produce unhealthy waste. They are also considered unsafe and expensive methods. An alternative technology is needed to synthesize nanoparticles that consume less energy and are more environmentally friendly. In this research, a CuO/TiO2 nanocomposite has been synthesized with a mole ratio of 1.5:1, which produces good energy and no environmental pollution using an easy and fast method (electrochemical). The morphology and structure of the nanocomposite were examined using TEM, FESEM, AFM, and FTIR. The particle size of the CuO/TiO2 nanocomposites was found to range between 10.52 and 88.10 nm, while optical properties were diagnosed using UV-visible spectroscopy since its measurements showed the amount of gap energy (3.08 eV). The structure of the nanocomposite was demonstrated using X-ray diffraction (XRD), where the mixed anatase and rutile phases were observed for TiO2, while the monoclinic (tenorite) phase was observed for CuO. Additionally, dye-sensitized solar cells (DSSCs) have been fabricated from CuO/TiO2 nanocomposite, which was synthesized by a new green method, and pigments (methylene blue as a chemical dye and chlorophyll as a natural dye). These DSSCs were characterized by their high ability to absorb ultraviolet energy, where the efficiency of energy conversion ɳ of ITO-CuO/TiO2 was approximately 2.62 and 3.87% with chlorophyll (a natural dye) and methylene blue (a chemical dye), respectively, where ɳ of ITO-CuO/TiO2 with methylene blue is the best.

Investigation of the effect of oxygen flow modulation on ITO film properties to improve the performance of SHJ solar cells

Photovoltaics offer a sustainable solution for the growing energy needs of the world, while reducing environmental impact. Transparent Conductive Oxides (TCOs), which are essential in photovoltaic technology, offer high light transmittance and effective charge carrier extraction. This research focuses on the impact of oxygen (O2) flow rates in the deposition of indium tin oxide (ITO) films on n-type crystalline silicon (c-Si) substrates by DC magnetron sputtering. The structural, optical, and electrical properties were analyzed. Based on the results, the optimal O2 ratio was determined and used in the fabrication of SHJ solar cells, achieving an efficiency of 18.6%.

Synthesis of conjugated structural copolymer poly(3-hexylthiophene-random-benzoyl dithieno[3,2-b:2’,3’-d]pyrrole) by electrochemical method

Electrochemical copolymer synthesis of benzoyl dithieno[3,2-b:2’,3’-d]pyrrole and 3-hexylthiophene (3HT) promises to create new polymer with suitable improved HOMO and LUMO with the energy level of acceptor compounds such as Fullerene (C60) or the novel accepted organic compound in the heterojunction in organic solar cell. Electrochemical synthesis of copolymer (3-hexylthiophene-random-benzoylbdithieno[3,2-b:2’,3’-d]pyrrole by linear potential scanning method was studied and applied for synthesis of conjugated copolymer where three electrodes have been used for polymerisation including the working electrode of Indium Tin Oxide (ITO) substrate, the reference electrode of Ag/AgCl in saturated KCl and the counter electrode of platinum wire. The synthesised copolymer was characterised and evaluated through an electrochemical process, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and ultraviolet-visible spectroscopy (UV-Vis) measurements. The synthesised copolymer has a bandgap of 2.09 eV, HOMO and LUMO energy levels of -5.21 and -3.12 eV, respectively. The HOMO-LUMO of the synthesised conjugated copolymer is closed with the HOMO-LUMO of Fullerene; therefore, the conjugated copolymer is a potential material for the fabrication of organic solar cell.

Nanosecond laser-induced crystallization of SiOx/Au bilayers in air and vacuum

High-quality polycrystalline silicon films on low-cost and low-temperature substrates have attracted much attention as promising materials for high-speed thin-film transistors and thin-film solar cells fabrication. To obtain poly-Si films on low temperature substrates, several concepts have been proposed. Usually the amorphous material undergoes crystallization which can be achieved by various methods including solid-phase crystallization, metal-induced crystallization or liquid-phase crystallization. In this work, we tried to combine the advantages of metal-induced crystallization and liquid-phase crystallization. To achieve this we explored the nanosecond laser crystallization of a bilayer structure consisting of Au and SiO0.1 layers with thicknesses of 30 nm and 130 nm, respectively. The study reveals that when exposed to 532 nm wavelength radiation leads to its destruction due to rupture. On the other hand, when subjected to 1064 nm wavelength radiation, no similar material behavior is observed, and the measured modification threshold is 0.15 J/cm2, representing a 40 % reduction compared to SiO0.1 film without gold. It is demonstrated that at laser fluences of 0.35 J/cm2 and higher, the treatedsurfaceinair becomes enriched with silicon dioxidenanoporous coating, attributed to the return of evaporation products to the target surface. Theoretical modeling, assuming thermal evaporation of the coating, suggests that the undesirable nanoporous layer formation can be avoided.

Impact of post deposition treatment on optoelectrical and microstructural properties of tin sulfide thin film for photovoltaic applications

Tin sulfide (SnS) has attracted significant interest due to its advantageous optoelectrical characteristics and abundant presence in nature. Post-deposition treatments (PDTs) are frequently employed to enhance the crystallinity of chalcogenide-based solar cells. This study examined the influence of the post-deposition heat treatment procedure on thermally evaporated SnS thin film. The post-deposition annealing process, as determined by XRD and AFM studies, supplies the necessary thermal energy for re-crystallization, potentially resulting in a modification of crystallite dimensions. The occurrence of Sn-S polytypes was examined using Raman and XPS studies. Annealing causes changes in the optical properties, as observed through optical analysis, which can be attributed to the improvement in crystallinity. Subjecting the material to annealing at temperature of 300 °C greatly improves both mobility and conductivity, while also causing a change in conduction type. The observed variations in conduction type are attributed to the differing ratios between the amounts of Sn2+ and Sn4+. This strategy offers a novel route for the fabrication of thin-film photovoltaic cells by using a p-type buffer layer.

First Principles Calculations of Novel Binary Transition Metal Oxides NaCr0.5X0.5O2 (X = Y, Tc, Rh) for Na-Ion Batteries

Recently, layered transition metal oxides have demonstrated voltage windows favorable for use as cathodes in sodium-ion batteries, leading to increased specific capacity and energy density. Here, NaCr0.5Y0.5O2, NaCr0.5Tc0.5O2, and NaCr0.5Rh0.5O2 were studied by using first-principles calculations to elucidate their properties. There is a trigonal arrangement in the structure of both pure and substituted NaCrO2. Structural characteristics reveal the ferromagnetic behavior of these compounds (NaCr0.5X0.5O2; X = Y, Tc, Rh). We calculated the density of states and spin-polarized electronic band structures for the three compounds tested. NaCr0.5Y0.5O2 and NaCr0.5Rh0.5O2 exhibit diluted magnetic semiconductor (DMS) behavior, while NaCr0.5Tc0.5O2 has half-metallic (HM) behavior. The substitutional material’s ferromagnetic nature is confirmed by the negative values of the exchange constants (Nօ α and Nօ β). The fractional value of the magnetic moment also confirms the DMS nature of NaCr0.5Y0.5O2 and NaCr0.5Rh0.5O2, while the HM behavior is confirmed by the integral value of the magnetic moment for NaCr0.5Tc0.5O2. The thermoelectric characteristics were computed using the BoltzTraP code. Alectrochemical analysis of NaCr0.5Y0.5O2 showed a theoretical discharge capacity of 400 mhAg−1 and an average intercalation voltage of 4.87 V, calculated from the total energies of the optimized compounds and their de-sodianted phases. These theoretical computations demonstrate that the binary layered TM oxides studied are appropriate substances to employ in coin cell fabrication as cathodes.

Review Metode Deposisi Elektrokimia Cu2ZnSnS4 sebagai Lapisan Absorber Sel Surya Lapisan Tipis

Cu2ZnSnS4 is a low-cost and environmentally friendly thin layer solar cell absorber material. The electrochemical deposition method is intended to study because it enables producing films with high homogeneity based on solution precursors. This research review focuses on examining the CZTS electrochemical deposition method in order to identify the effect of the sulfurization process (sulfurization temperature and time) so that the best electrochemical deposition process can be identified for future work of high-efficiency CZTS thin layer solar cell fabrication based on solution precursor. The results show that the Cu2ZnSnS4 layer deposited through the electrochemical method has a 1.4-1.6 eV bandgap range. The etching process to post-annealing 0.1M KCN is crucial to effectively and selectively remove CuS, ZnS, and Cu6Sn5 secondary phases.

Design of 2.5-D miniaturized frequency selective surface with enhanced oblique stability

This paper presents a miniaturized 2.5-D frequency selective surface (FSS) that exhibits a band stop response at frequency of 1.5 GHz. In the unit cell, the meander patterns on both side of the substrate are connected in series by four vias. Moreover, the meandered pattern in each quadrant is also connected with one of the meander patterns of the adjacent unit cell. In this manner, a 2.5-D closed loop is created with large perimeter. The enlarged perimeter amplifies the effective inductance and leads to a decrease in both the resonant frequency and the dimensions of unit cell. Subsequently, the proposed FSS demonstrates excellent miniaturization with an overall size of 0.038 λ 0 × 0.038 λ 0. Moreover, the frequency response is highly stable up to 86° for both TE and TM polarization. The resonance mechanism of the designed FSS is explicated through distribution of surface current and electric field. The testing board of the proposed FSS has been fabricated for the verification of the design. The measured frequency response of the prototype are congruent with the simulation results. The distinguished features of the constructed structure are enhanced angular stability, miniaturized unit cell, low profile, simple geometry and easy fabrication.

Supernanoporous SnO2 particles and spheres as sustainable solar cell constituents

This study presents the synthesis and a comparative report of the properties of supernanoporous SnO2 particles SNSP (0D) supernanoporous SnO2 spheres SNSS (3D) formed with an assembly of SNSP with a view to examine their application as effectual photoanodes in sustainable solar energy conversion. Porosity imposed nanoparticles with extended surface area improve photon interaction and charge transfer by increasing the absorption of light, hence addressing the existing efficiency hurdles in solar cells. SNSP with particle size of ∼23 nm and SNSS with particle size and sphere size of ∼26 nm and ∼800 nm, respectively, were synthesized by treating SnCl4 via solvothermal process at different experimental conditions. Important aspects of the as-synthesized SNSP and SNSS samples, such as the crystal structure, particle size, optical behaviour, identification of elements present, were characterized by powder X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Ultra Violet Diffuse Reflectance Spectroscopy (UV-DRS) and Energy Dispersive Analysis X-ray (EDAX) Spectroscopy techniques. Field dependent dark and photoconductivity studies reveal significant rise in the photoconducting nature, opto-electrical and surface properties of SNSP and SNSS. Pore size distribution and specific surface area of SnO2 particles and spheres were measured by Brunauer-Emmett-Teller (BET) analysis. High Resolution Transmission Electron Microscopy (HRTEM) is performed to analyze the size and shape of the porous SnO2 particles and spheres and further to correlate the data derived from FESEM. From other prevailing applications of porosity imposed nanomaterials such as gas sensing, catalytic and photodegradation the innovation of this work is to depict the novelty of porous SnO2 particle and sphere with highlighting thermal stability to instigate into the charge transport property suitable for solar cell application. The results were analyzed evincing the photovoltaic properties of spheres over particles and hence the PSC constituent among SNSP and SNSS with better proficiency was identified as appropriate photoconducting medium for fabrication of sustainable photovoltaic cells.