Layer In Dye-sensitized Solar Cells Research Articles

Preparation of the scattering layer based on SnO2 nanocrystals for dye sensitized solar cell application

Abstract In this work, SnO2 paste was prepared based on (0.1 and 0.12 g) of SnO2 nanoparticles. The SnO2 film was deposited using Screen printing and doctor blade techniques, which it employed as scattering layer in Dye-Sensitized Solar Cell (DSSC). The crystal structure, morphology, and thermal stability of the paste were investigated using XRD, FE-SEM, and TGA techniques. The DSSC parameters were achieved to examining the effect of scattering layer on performance of DSSC. The results showed a crystalline structure predominantly composed of rutile SnO2 crystals arranged in a tetragonal pattern, with individual crystallites measuring approximately 100 nanometers in size. SEM images depicted the surface of SnO2 resembling a sponge with fine pores facilitating dye adsorption and electron mobility. Moreover, a decrease in average particle size was observed with increasing dye concentration, with the average grain size of SnO2 particles being below 100 nanometers at lower dye concentrations. TGA measurements indicated a phase transition occurring around 400 °C.

Effect of ball milling time on Sr0.7Sm0.3Fe0.4Co0.6O2.65 perovskites and their application as semiconductor layers in dye-sensitized solar cells

The practical utilization of TiO2 as a semiconductor in dye-sensitized solar cells (DSSCs) has been set back by poor visible light absorption, high charge carrier recombination, and low electrical conductivity, which reduce the power conversion efficiency (PCE) and sustainability of the device. In this respect, perovskites with excellent properties, such as large surface area, good optical properties, high electrical conductivity, and superior electrochemical stability, have recently emerged as promising alternatives capable of overcoming the drawbacks of TiO2. Herein, Sr0.7Sm0.3Fe0.4Co0.6O2.65 (SSFC) perovskites were prepared via the ball milling method at various milling times of 0, 5, and 10 h, and the obtained samples were denoted by SSFC-0, SSCF-5, and SSCF-10, respectively. Increasing the ball milling time led to a significant reduction in nanoparticle size and agglomeration, which, in turn, increased the surface area and electrical conductivity of the samples. As a consequence, the SSFC-10 perovskite exhibited the smallest average particle sizes (18.9 nm) with the largest surface area (61.8 m2 g−1) and minimum defects, which allowed for efficient electron transport, resulting in the best electrical conductivity of 49.8 S cm−1. Ultimately, DSSCs fabricated using SSFC-10 semiconductor layers achieved an optimum PCE of 6.01 %, which is an improvement of 8.67 %, 1.1 %, and 6.56 % for SSFC-0 (3.69 %), SSFC-5 (4.96 %), and TiO2 (5.64 %), respectively. Thus, varying the ball milling time can be used as an effective technique to tailor the physicochemical properties of SSFC to suit desired applications, particularly the fabrication of highly efficient and sustainable DSSC semiconductor layers.

Optimization of preparation conditions by response surface methodology for synthesis of titanium dioxide/reduced graphene oxide composite in dye-sensitized solar cells

This study aimed to address the need for alternative materials in the anode layer to enhance the performance of dye-sensitized solar cells (DSSCs). The synthesis of titanium dioxide/reduced graphene oxide (TiO2/rGO) was carried out using the response surface methodology by face central composite design (RSM/FCC). This method allowed us to systematically evaluate the influence of two key factors, namely the weight percentage of precursor graphene oxide (GO wt%) and the L-ascorbic acid ratio, | on the power conversion efficiency (PCE) of DSSCs. Our research is significant because it explores the synthesis of TiO2/rGO as a novel material for the anode layer in DSSCs. This material holds promise for improving device performance due to its unique properties, such as enhanced charge transport and light harvesting capabilities. Additionally, TiO2/rGO can serve multiple functions within the DSSCs device, acting not only as a charge transport layer but also potentially as a light scattering layer to increase photon absorption. The statistical analysis revealed that the GO wt% had a more significant influence on PCE compared to the L-ascorbic acid ratio. Furthermore, our simulation results demonstrated high validity and accuracy, with a correlation coefficient (R2) of 0.9988 and a residual standard error of less than 5 %. The optimized DSSCs-based TiO2/rGO anode achieved a remarkable PCE of 7.12 %, representing a 29 % improvement compared to the pure TiO2-based DSSCs anode. In summary, our study highlights the importance of synthesizing TiO2/rGO as a novel material for the anode layer in DSSCs and demonstrates its potential for significantly enhancing device performance. This study emphasizes these key points more prominently in the abstract to better convey the novelty and significance of our findings.

Exploring the potential of porphyrin-based materials for organic solar cells supported on carbon: A quantum chemistry approach

In this work, novel solar cell materials are studied by using first-principle calculations to improve the electronic structure properties and thus enhance the hypothetical efficiency in the active layer of dye-sensitized solar cells (DSSCs). The modeling of 75 composite systems is explored, based on the interaction of three molecular structures; namely graphene, a linker, and metalated porphyrins (a base species and the coordinated cases with Mg, Cu, Ni, and Zn). The stability and electronic structure properties of 10 composite systems, screened from the original set, were analyzed as potential candidates to be implemented in solar cell devices. All calculations were performed using density functional theory (DFT). This study is intended to screen systems that broaden the range of the absorption spectra in the composite materials of the form porphyrin/carbon by improving the electron transfer properties. The methodology to obtain the final set of selected composite materials may be considered a guide in the design of novel DSSC systems.

Optimization of power conversion efficiency of BaTiO3 as a compact layer in DSSC using response surface methodology/Box-Behnken design

This study focused on the optimization of BaTiO3 thin film as a compact layer in a dye-sensitized solar cell (DSSC) by spin-coating method. The experiment was designed using response surface methodology with Box-Behnken design (RSM/BBD). Three key parameters were studied i.e., annealing time, annealing temperature and the number of drop-casting. Three independent variables and three levels were used in the experiment involving 17 experiments to analyse the optimum deposition condition. The interaction between these factors was studied and used to identify the best parameters to improve the DSSC performance. The statistical analysis showed that the three parameters studied significantly affected the power conversion efficiency (PCE). After optimization of parameters, a specific optimum deposition condition, A = 3 h (annealing duration), B = 485 °C (annealing temperature) and C = 3 (number of drop-casting) was obtained. According to the optimum condition, the predicted PCE value was 4.87%. A validation experiment was carried out and a PCE of 4.92 ± 0.04% was achieved, which is in good agreement with the predicted result.

Layered Fe-doped SrLaInO4 perovskite electron transport layer for dye-sensitized solar cell with high open-circuit voltage

This study presents the synthesis of SrLaInO4 perovskite oxides using a high-temperature solid-phase method under atmospheric pressure, with varying Fe-doping concentrations incorporated during fabrication. The synthesized particles underwent characterization using X-ray diffraction and electron microscopy, revealing a layered crystal structure. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy were employed to confirm the successful incorporation of Fe into the SrLaInO4 crystal structure. Significantly, Fe-doping was observed to broaden the light absorption range of the perovskite oxide whilst simultaneously reducing the bandgap. When employed as the electron transport layer in dye-sensitized solar cells, Fe-doped SrLaInO4 perovskite exhibited a maximum efficiency of 4.64%, alongside an open-circuit voltage (VOC) of 0.801 V, which was noticeably higher than that observed in identically-prepared cells employing TiO2 as the electron transport layer.

Designing photoelectrode architecture modified with mesoporous MCM-41/CeO2 composites as specific scattering layers for dye-sensitized solar cells

Depositing light scattering film on top of the photoactive layer of dye-sensitized solar cells (DSSCs) is one method to boost the device efficiency. Therefore, mesoporous MCM-41 and CeO2 were prepared and coated on TiO2 photoactive layer in both their pure and composite (1–4 wt% CeO2:MCM-41) forms by doctor blade technique. XRD, FESEM, EDS, TEM, BET, FTIR, DRS, and PL analyses were employed to characterize all compounds. Additionally, the power conversion efficiency (PCE), dye adsorption capacity, and charge transfer parameters of various DSSCs were measured. The data taken from J-V plots indicated that the highest conversion efficiency belonged to 2 wt% CeO2:MCM-41 when was used as the scattering layer which could boost the efficiency up to 7.42% with fill factor (FF), open-circuit voltage (Voc) and short-circuit current density (Jsc), respectively, equal to 0.48, 0.752 V, 20.55 mA.cm−2, confirming 78.8% greater efficiency than the bare TiO2 containing DSSC (PCE = 4.15%, FF = 0.39, Voc = 0.736 V, Jsc = 14.45 mA.cm−2). In fact, once 2 wt% CeO2:MCM-41 with large particles was applied, according to Mie's theory, prolonged the light path through incident light scattering, which resulted in more light harvesting by photoanode material, further dye molecules excitation, and improvement in the current density. Also, because of the insulating nature of silica material in 2 wt% CeO2:MCM-41 layer, it reduced the charge recombination process and accelerated the transfer of electrons from the TiO2 photoanode to the Pt counter electrode via the external circuit. Besides, high porosity and huge surface area (757.34 m2/g) of 2 wt% CeO2:MCM-41 promoted dye molecules to be adsorbed additionally which generated extra photoelectrons.

Flexible PET/(PET-TiO2) core/shell nanofibrous mats as potential photoanode layer for dye-sensitized solar cells, DSSCs

In this detailed study, high porous flexible structures composed of polyethylene terephthalate (PET) and a PET composite comprised of titanium dioxide (PET-TiO2) core/shell nanofibrous mats were developed using coaxial electrospinning technique. Two different TiO2 shapes (nanobars and nanorhombics) were developed, using the solvothermal synthesis method, then incorporated at various contents (0–20 wt%) in the shell layer of the nanofiber to improve the optical, thermal, and mechanical properties of their corresponding fibrous mats to use them as alternative porous structures to the brittle porous TiO2 based photoelectrode presently used. The surface morphology, porosity, specific surface area, thermal stability, dye adsorption, optical and mechanical properties of the so developed nanofibrous mats were investigated. Emphasis was to the effect of solvent miscibility and solvent composition on fibrous mats' morphology. The successful incorporation of TiO2 nanoparticles inside the nanofibers’ shell was confirmed by various characterizations techniques. It was observed that addition of up to 15 wt% TiO2 shifted the UV–Visible absorption of the of the so developed nanofibrous mats to larger wavelength. Moreover, PET/(PET-TiO2) core/shell nanofibrous mats obtained with nanobars TiO2 showed higher thermal stability due to a better TiO2/PET interfacial interaction. Photoluminescence results confirmed the efficient charge transfer between TiO2 nanoparticles and PET with a minimum recombination of the photogenerated charges.

Potential of transition metal sulfides, Cu2ZnSnS4 as inorganic absorbing layers in dye-sensitized solar cells

Organic dye sets a benchmark for dye-sensitized solar cells (DSSCs) application. Replacing the organic dyes with inorganic phases poses a significant challenge. Without organic dyes, efficiency decreases dramatically due to loss of charge transfer. Thus, surface modification techniques are widely considered to be the key to reducing the electron recombination, suppressing the dark currents and increasing efficiency of DSSC. Using multiple absorbent materials with different energy gaps/band gap values could broaden the DSSC's photon absorption range. This study investigated the potential applications of transition metal sulfides (TMS), kesterite (Cu2ZnSnS4, CZTS) as a promising inorganic absorber layer of DSSCs. Based on the current-voltage measurement, a lower molar ratio of milled CZTS compared to the N719-dye produced a stable DSSC with a power conversion efficiency (η), short-circuit current density (Jsc), and open-circuit voltage (Voc) of 4.75%, 13.99 mA cm−2, and 0.75 V, respectively. Furthermore, incident photon-to-current efficiency (IPCE) analysis exhibited an improved number of incident photons harvested by standard DSSC from 60% to 85% with and without the presence of CZTS. Even when light harvesting reached up to 80%, a higher concentration of CZTS content compared to the N719 dye produced an unstable solar cell device with a low Jsc and η due to electron loss through the recombination process. This was confirmed by the recombination resistance (Rrec) determined by the impedance spectroscopy (EIS), which found that the suppression of the Rrec at a lower ratio concentration between CZTS/N719-dye generated the highest η. The results that the use of the closest concentration of inorganic and organic co-sensitizers can improve the stability and overall performance of the developed DSSC. This approach has been regarded as the most sustainable economically viable means of producing cheap solar cells to convert the largest amount of energy from the solar spectrum to electricity.

Fabrication of bimetallic inlaid working electrode for highly efficient dye sensitized solar cells

Gold nanoparticles (AuNPs) including Au-Pink, Au-Orange, Au-Purple, Au-Blue were synthesized using chemical reduction method, their optical and morphological properties were characterized and they were used in PV devices. The active layer of dye-sensitized solar cells having titanium dioxide (TiO2) solid microsphere (MS) made up of nanoparticles granules were coated with AuNPs. This Au-TiO2 MS hybrid DSSC boosted light harvesting, charge separation, and improved the charge transportresulting in an improvement of both short circuit current and open circuit voltage. The power conversion was boosted 16% compared to the control photoanode of TiO2 solid microsphere. Further enhancement in the short circuit current was observed during the incorporation of both Au and Ag, bi-metallic nanoparticles in the TiO2 matrix. An overall photo to electron conversion efficiency of 8.73% was obtained due to the plasmonic cooperation effect of TiO2-Ag-Au hybrid structures, which is 65% increase over pure TiO2 DSSCs. The local electrified intensity enhancement around the individual Ag, Au nanoparticles and plasmonic coupling of the Ag-Au combination have been used to explain these results with finite-difference time-domain simulation.

ZnFe2O4 spinel oxide incorporated photoanodes as light-absorbing layers for dye-sensitized solar cells

Herein, nanoparticles of zinc ferrite (ZnFe2O4) were initially synthesized by chemical co-precipitation method followed by ultrasonication. Then mixed with TiO2 (P25), and subsequently used as photoanode for dye-sensitized solar cell. ZnFe2O4 nanocomposites were found to be active in the visible region of the solar spectrum, while P25 showed absorption in the UV region, demonstrating a possibility of wider absorption band and higher photoelectric conversion efficiency. Composite photanode (with 0.1 wt% ZnFe2O4) based cell showed high power conversion efficiency (PCE) of 4.55%, whereas, the PCE of the cell with pure TiO2 as photoanode was 3.27%. Thus, there was an 39% enhancement of PCE for the composite photanode based cell..

Evaluating the photoelectric performance of D-π-A dyes with different π-conjugated bridges for DSSCs

In the synthesis experiment (Dyes Pigm., 2020, 174, 108026), it was found that the 10 and 11 dyes have the excellent red-shift value in the absorption spectrum, so we replaced the conjugated bridges of 10 and 11 by introducing different functional groups, four novel dyes (A, B, C, D) are designed as the photoactive layers of dye-sensitized solar cells (DSSCs). Compare with other dyes, it is worth noting that the designed dye B displays the narrowest energy gap, the most obvious red shift of absorption peak (∼545 nm), the best charge separation ability and the most outstanding electron transport performance.

Poly(3,4-ethylenedioxythiophene) decorated MXene as an alternative counter electrode for dye-sensitized solar cells

Counter electrodes (CE) layer in dye-sensitized solar cells (DSSCs) are possibly the most exorbitant material due to the presence of scarce earth metal, platinum (Pt). The prospective substitution of a Pt-CE would effectively pave the way for broad commercialization of the DSSC technology. In this regard, this work is focused on the fabrication of poly(3,4-ethylene dioxythiophene) decorated MXene (PEDOT@Ti3C2Tx) composite electrode, and its performance as a CE in DSSC was tested for the replacement of high-cost Pt-CE. The 2D-Ti3C2Tx was initially synthesized by the selective chemical etching method, followed by the electro-polymerization of 3,4-ethylenedioxythiophene (EDOT) monomer on the Ti3C2Tx surface. Further, X-ray diffraction (XRD), Raman, high-resolution scanning electron microscopy (HR-SEM), and X-ray photoelectron spectroscopy (XPS) characterization results confirm the successful formation of the PEDOT@Ti3C2Tx composite. PEDOT@Ti3C2Tx-CE display a strong electrocatalytic activity toward the iodide/triiodide electrolyte and good charge transfer kinetics with low charge transfer resistance close to the performance of the Pt electrode, as shown by electrochemical experiments. On the other hand, further testing of the device fabricated with thermally decomposed Pt-CE DSSCs achieved an efficiency of 8.7% under simulated 1SUN light at AM1.5G, whilst the DSSC built with the as-prepared composite material had 7.12% efficiency under the same conditions. PEDOT@Ti3C2Tx-CE composite DSSC outperformed PEDOT-CE and Ti3C2Tx-CE DSSC in power conversion efficiency improvements (PCE), demonstrating that PEDOT@Ti3C2Tx composite possesses a strong catalytic activity with noticeable charge transfer and mass transport capabilities. Therefore, the as-fabricated composite film takes utilization of the conductivity and electrocatalytic capabilities of the two components, increasing the overall power conversion efficiency of DSSC. The 15-days stability investigation demonstrates that the PEDOT@Ti3C2Tx-CE-based DSSC exhibits a consistent performance and corrosion resistant toward the iodide/triiodide redox electrolyte. Therefore, overall performance level of the PEDOT@Ti3C2Tx-CE thus entices more study for the replacement of Pt in DSSC and is indeed evinced to be a prospective noble metal electrode contender.

(Invited) Persistently Luminescent Nanoscale Materials

Although alkaly earth aluminates (such as SrAl2O4 doped with Europium and Dysprosium) have been investigated as persistently luminescent (PL) materials for several decades, multiple questions still remain unanswered about their nanoscale optoelectronic properties, microscopic characterization, and their utilization in specific devices, such as, for example, after-glowing solar cells. In this talk, I will review what the scientific community, and my group, have been learning on SrAl2O4(:Eu:Dy) using nano-optical characterization tools, including scanning near field optical microscopy (SNOM) luminescence imaging to inform device fabrication. Specifically, I will review phase phase-modulated scanning near-field optical luminescence (PM-SNOL) imaging as new method for assessing the exciton diffusion length (LD) in nanoscale PL materials. Using PL we have determined that LD is of the order of 100 μm in SrAl2O4(:Eu:Dy), a surprisingly large value, that should enable exciton storage and transfer from SrAl2O4(:Eu:Dy) micro- and nano-crystals, as opposed to simple exciton recombination with photon re-emission. With this result in mind, in the second part of our talk, we will we introduce a new family of photovoltaics capable of generating power in the dark for several hours after illumination, thanks to the afterglow redox properties of strontium aluminate codoped with Eu2+ and Dy3+ [SrAl2O4(Eu,Dy)], a persistently luminescent material incorporated at the interface between the transparent anode and the active layer of dye-sensitized solar cells (DSSC). After 9-hr operation in the dark, our photovoltaics still produce dark short-circuit currents about 75% of the current generated immediately after illumination. Control DSSCs with identical architecture, but without SrAl2O4(Eu,Dy), do not exhibit any significant generation of power in the dark. Differently from previous unsuccesful attempts to design nighttime solar cells seeking use of the reabsorption of photons persistently emitted by SrAl2O4(Eu,Dy) in relatively inefficient processes, our devices rely on the more efficient integration of Eu2+/Eu3+ and Dy3+/Dy2+ redox processes of SrAl2O4(Eu,Dy) into the electrochemistry of DSSCs, with the suppression of persistent luminescence, the direct oxidation of the iodine electrolyte by Eu3+,and the reduction of the DSSC anode by Dy2+. With the discovery of charge transfer and redox processes between strontium aluminate, titania and iodine electrolytes, our work also offers unique advances in the photo-physics of PL materials at the nanoscale.

Upconversion photoluminescence enhancement by Gd-doped NaYF4:Yb,Er@SiO2 nanoparticles and their application in dye-sensitized solar cells

Introducing upconversion nanoparticles (UCNPs) onto photoanode films is an effective way to enhance the photovoltaic performance of dye-sensitized solar cells (DSSCs). In this contribution, the β-NaYGdF4:Yb, Er UCNPs and β-NaYGdF4:Yb,Er@SiO2 nanoparticles (NPs) were prepared by tuning the dopant contents of the Gd ions and the β-NaYGdF4:Yb,Er@SiO2 NPs were applied as an upconverting layer in DSSCs. Upconversion photoluminescence indicates that the UCNPs doped with 5% Gd ions exhibit the strongest green and red fluorescence emissions. Moreover, the DSSCs device incorporating the NPs with 5% Gd ion dopant can achieve an optimal photovoltaic efficiency of 5.89%, which is 20.20% enhancement in comparison to the device without NPs and 16.17% increasement with respect to the device containing β-NaYF4:Yb,Er@SiO2 nanocrystals, thus highlighting the effect of the doping of the Gd ions in nanoparticles on their upconversion photoluminescence and photoelectric performance. Accordingly, the current results offer a feasible strategy for further regulating the photoluminescence property of UCNPs and optimizing the photovoltaic performance of UCNPs-based DSSCs devices.

Hybrid TiO2 Nanorods Combined with a Buffer Layer for Dye-Sensitized Solar Cells

Hybrid TiO2 Nanorods Combined with a Buffer Layer for Dye-Sensitized Solar Cells

Assessment of TiO2 Blocking Layers for CuII/I-Electrolyte Dye-Sensitized Solar Cells by Electrochemical Impedance Spectroscopy.

The TiO2 blocking layer in dye-sensitized solar cells is the most difficult component to evaluate at thicknesses below 50 nm, but it is crucial for the power conversion efficiency. Here, the electrode capacitance of TiO2 blocking layers is tested in aqueous [Fe(CN)6]3–/4– and correlated to the performance of photoanodes in devices based on a [Cu(tmby)2]2+/+ electrolyte. The effects of the blocking layer on electronic recombination in the devices are illustrated with transient photovoltage methods and electrochemical impedance analysis. We have thus demonstrated a feasible and facile method to assess TiO2 blocking layers for the fabrication of dye-sensitized solar cells.

Dye extracted from Bael leaves as a photosensitizer in dye sensitized solar cell

This study has explored a new plant source, Bael tree leaves, as an efficient dye extraction towards green energy harvesting through dye-sensitized solar cells (DSSCs). The photosensitizers, photo-absorption, bandgap, and ionic conductivity characteristics of the extracted dye were determined using thin-layer chromatography (TLC), ultraviolet-visible spectroscopy, Tauc plot, and conductivity meter, respectively. Chlorophyll is the main constituent in the extracted dye confirmed by TLC analysis. An optimum concentration (0.2 g ml−1) with ionic conductivity of 455 μS cm−1 of the dye was used as a photoactive layer in DSSC, demonstrating power densities of 1.345 μW m−2 and 8.078 μW m−2 under the illumination of the LED lamp (1555 lx) and tungsten bulb (1926 lx), respectively. Additional parameters, including fill factor (0.26), ideality factor (1.25), characteristic resistance (309 Ω), series resistance (313 Ω), and shunt resistance (662 Ω) of the fabricated DSSC under tungsten illumination reveal that the novel Bael tree leaves-based dye can harvest green energy efficiently through DSSCs.

Investigating the Tradeoff Between Transparency and Efficiency in Semitransparent Bifacial Mesosuperstructured Solar Cells for Millimeter-Scale Applications

This article thanks to recent advancements in nanofabrication and 3-D packaging, typical Internet of Things devices can now be wirelessly controlled using millimeter-scale sensors known as Internet of Tiny Things devices. Since these low-power devices may be exposed to low and indirect solar irradiation, we demonstrate a novel mesosuperstructured solar cell (MSSC) that allows low flux light to be harvested from both its top and bottom sides. Our cell is based on either a dye-sensitized solar cell (DSSC) or a perovskite solar cell (PSC). The active layer in the proposed MSSCs was tuned to allow semitransparent behavior. Moreover, we developed an experimentally validated model that enables optimization of the active layer thickness for different semitransparent MSSC applications. In MSSCs, such optimization is necessary to balance the tradeoff between transparency and efficiency for various active layer thicknesses. Fabricated DSSCs and PSCs cells were used to validate the simulation results. The fabricated DSSC achieved a harvesting ratio of 1:10 with a conversion efficiency of around 2% at one Sun. We demonstrate that the optimum thickness of the mesoporous TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> active layer in DSSCs was 800 nm, enabling a maximum power density of 7 mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> .

Application of Bunchy TiO2 Hierarchical Microspheres as a Scattering Layer for Dye-Sensitized Solar Cells

A novel bunchy TiO2 hierarchical microspheres composite nanostructure with strings of anatase TiO2 hierarchical micro-spheres and rutile nanobelts framework (HSN) was synthesized via an one-pot hydrothermal process. This new structure presents great specific surface area, large pore size distribution, homogeneous three-dimensional (3D) structure, high crystallinity and excellent light scattering performance simultaneously. The bi-layer photoanode film was successfully prepared which TiO2 P25 as absorption layer and HSN as an efficient scattering layer on the top of TiO2 P25 film in dye sensitized solar cells (DSSC). The bi-layer DSSC taken on a great progress in the power conversion efficiency (PCE) achieved 8.08%. However, the PCE of single and double layer TiO2 film DSSCs just showed 6.72% and 3.67% respectively. Such improvement was mainly because of the efficient scattering centers (HSN) which can bring the enhanced dye loading, fast charge transfer and excellent light harvesting efficiency.