Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• deposition system (Kurt J. Lesker) for deposition of Ca (20 nm, 1.0 Å∙s−1) and Al (100 nm, 2.0 Å∙s−1) top electrodes (10.18 ± 0.1 mm2). The electrical characterization was performed in a glovebox. Current-density–voltage (J–V) curves were measured using a Keithley 2400 source measure unit. The photocurrent

Molecular architectonics of DNA for functional nanoarchitectures

• Debasis Ghosh,
• Lakshmi P. Datta and
• Thimmaiah Govindaraju

Beilstein J. Nanotechnol. 2020, 11, 124–140, doi:10.3762/bjnano.11.11

• the dTn chain length and temperature [85]. The multichromophoric array of NDI and oligo-dTn assembled over a gold substrate showed photocurrent generation due to electron conduction because of the π‐stacked array of the NDI assembly. In their next design approach, two separate zinc binding systems, Zn

• photocurrent (Figure 7b). However, the randomly assembled array of DPPNDI–dT40 immobilized across the gold electrode was unable to generate any photocurrent response owing to ground-state CT complexation of DPP with NDI in their random arrangement (Figure 7c). Tanaka, Ono, and co-workers reported the

Semitransparent Sb₂S₃ thin film solar cells by ultrasonic spray pyrolysis for use in solar windows

• Jako S. Eensalu,
• Atanas Katerski,
• Erki Kärber,
• Lothar Weinhardt,
• Monika Blum,
• Clemens Heske,
• Wanli Yang,
• Ilona Oja Acik and
• Malle Krunks

Beilstein J. Nanotechnol. 2019, 10, 2396–2409, doi:10.3762/bjnano.10.230

• photocurrent density and PCE (of 1.9%) in solar cells based on Sb2S3 layers grown by USP was due to a discontinuity of the Sb2S3 layer [28]. In our recent study, we showed that the discontinuity of Sb2S3 films grown by USP, and likely other chemical methods, is a result of 3D island growth [46]. We

• absorption coefficient curves of Sb2S3 and P3HT. The transmittance of light to the absorber is limited at higher photon energies by the onset of absorption of TiO2 at 3.0 eV and ITO at 3.6 eV. The P3HT layer, however, does not contribute to the generation of photocurrent [14][21]. On the contrary, any

• compared to <10 mm2 cells (Table 2) due to about three times larger RS (26 Ω mm2) and about three times smaller RSH (190 Ω mm2) under both illuminated (Figure 3d) and dark conditions (Figure S3 in the Supporting Information File 1). Also, the photocurrent loss in larger cells originates from the increase

Polyvinylpyrrolidone as additive for perovskite solar cells with water and isopropanol as solvents

• Chen Du,
• Shuo Wang,
• Xu Miao,
• Wenhai Sun,
• Yu Zhu,
• Chengyan Wang and
• Ruixin Ma

Beilstein J. Nanotechnol. 2019, 10, 2374–2382, doi:10.3762/bjnano.10.228

• precursor solution is found to be effective in increasing the Voc. The short-circuit photocurrent density (Jsc) exhibits no significant difference, which has also been manifested by measuring the external quantum efficiency (EQE) of the two samples over the entire wavelength range from 350 to 800 nm (Figure

Nontoxic pyrite iron sulfide nanocrystals as second electron acceptor in PTB7:PC₇₁BM-based organic photovoltaic cells

• Olivia Amargós-Reyes,
• José-Luis Maldonado,
• Omar Martínez-Alvarez,
• María-Elena Nicho,
• José Santos-Cruz,
• Juan Nicasio-Collazo,
• Irving Caballero-Quintana and
• Concepción Arenas-Arrocena

Beilstein J. Nanotechnol. 2019, 10, 2238–2250, doi:10.3762/bjnano.10.216

• OPV sets were fabricated and tested, and the results followed the same trend. Figure 6a shows the best values measured. The external quantum efficiency (EQE) plots of the OPVs are shown in Figure 6b. The EQE curves indicate that the photocurrent is generated mainly in the 400–750 nm range, in

Fabrication and characterization of Si_1−xGe_x nanocrystals in as-grown and annealed structures: a comparative study

• Muhammad Taha Sultan,
• Adrian Valentin Maraloiu,
• Ionel Stavarache,
• Jón Tómas Gudmundsson,
• Andrei Manolescu,
• Valentin Serban Teodorescu,
• Magdalena Lidia Ciurea and
• Halldór Gudfinnur Svavarsson

Beilstein J. Nanotechnol. 2019, 10, 1873–1882, doi:10.3762/bjnano.10.182

• impulse magnetron sputtering (HiPIMS). The as-grown structures subsequently underwent rapid thermal annealing (550–900 °C for 1 min) in N2 ambient atmosphere. The structures were investigated using X-ray diffraction, high-resolution transmission electron microscopy together with spectral photocurrent

• annealing results in the periodically arranged columnar self-assembly of SiGe core–shell nanocrystals. An increase in photocurrent intensity by more than an order of magnitude was achieved by annealing. Furthermore, a detailed discussion is provided on strain development within the structures, the

• consequential interface characteristics and its effect on the photocurrent spectra. Keywords: grazing incidence XRD (GIXRD); high-power impulse magnetron sputtering (HiPIMS); HRTEM; magnetron sputtering; photocurrent spectra; SiGe nanocrystals in SiO2/SiGe/SiO2 multilayers; STEM-HAADF; TEM; Introduction

Remarkable electronic and optical anisotropy of layered 1T’-WTe₂ 2D materials

• Qiankun Zhang,
• Rongjie Zhang,
• Jiancui Chen,
• Wanfu Shen,
• Chunhua An,
• Xiaodong Hu,
• Mingli Dong,
• Jing Liu and
• Lianqing Zhu

Beilstein J. Nanotechnol. 2019, 10, 1745–1753, doi:10.3762/bjnano.10.170

• power of 1.4 mW (power density: 1.78 mW/cm2). Then a strategy similar to the above-mentioned DC test was implemented to obtain the wavelength-dependent photocurrent. As is shown in Figure 4a and Figure 4b, in contrast to the current in dark environment (Idark), both 0° and 60° Ids curves show a

• nm and the power at 1.4 mW. Then a strategy comparable with the above-mentioned electronic test was performed to get the angle-resolved photocurrent with bias voltage of 5 mV. The real-time response curves are presented in Figure 5a, in which a more distinct photoelectric effect can be observed under

• the daylight illumination using a household lamp. Meanwhile, a rapid increase and decrease in current reached the saturation value and the minimum value within about 200 ms, achieved by switching the laser on and off. Figure 5b shows the magnified change of the 60° photocurrent curve achieved by

BiOCl/TiO₂/diatomite composites with enhanced visible-light photocatalytic activity for the degradation of rhodamine B

• Minlin Ao,
• Kun Liu,
• Xuekun Tang,
• Zishun Li,
• Qian Peng and
• Jing Huang

Beilstein J. Nanotechnol. 2019, 10, 1412–1422, doi:10.3762/bjnano.10.139

• efficiency of the samples, photoluminescence spectroscopy, photocurrent and electrochemical impedance spectroscopy were tested. The recombination rate of photogenerated carriers (electrons and holes) in photocatalysts was characterized by photoluminescence spectra. Generally, the lower the spectral intensity

• –hole separation and transfer, which can significantly improve the photocatalytic activity. Figure 10b shows the transient photocurrent response of the samples irradiated by visible light. The photocurrent is mainly generated by the migration and diffusion of photogenerated electrons and holes from the

• internal structure of the material to its surface [48]. BTD shows the most prominent photocurrent density, proving that the carrier recombination rate is low and the lifetime is long, which contributes to the enhancement of photocatalytic activity. Electrochemical impedance spectroscopy (EIS) is one of the

Construction of a 0D/1D composite based on Au nanoparticles/CuBi₂O₄ microrods for efficient visible-light-driven photocatalytic activity

• Weilong Shi,
• Mingyang Li,
• Hongji Ren,
• Feng Guo,
• Xiliu Huang,
• Yu Shi and
• Yubin Tang

Beilstein J. Nanotechnol. 2019, 10, 1360–1367, doi:10.3762/bjnano.10.134

• photocatalytic activity after three cycles. This decrease of photocatalytic performance is mainly due to the mass of catalysts being inevitably lost in the recycling process [39]. Photocurrent response and electrochemical impedance spectroscopy (EIS) measurements were carried out to obtain some insights into the

• photocatalytic activity of the Au/CBO composites. Figure 7a shows that both bare CBO and 2.5 wt % Au/CBO yield a photocurrent response under visible-light irradiation, but the photocurrent density of 2.5 wt % Au/CBO is much higher than that of the bare CBO. The combination of 0D Au NPs and 1D CBO microrods

• using 2.5 wt % Au/CBO as a photocatalyst. (c) First-order kinetics of the TC degradation curves using different photocatalysts. (d) Three consecutive runs of TC degradation over 2.5 wt % Au/CBO photocatalyst. (a) Photocurrent response and (b) EIS spectra of bare CBO and 2.5 wt % Au/CBO composite under

Synthesis of novel C-doped g-C₃N₄ nanosheets coupled with CdIn₂S₄ for enhanced photocatalytic hydrogen evolution

• Jingshuai Chen,
• Chang-Jie Mao,
• Helin Niu and
• Ji-Ming Song

Beilstein J. Nanotechnol. 2019, 10, 912–921, doi:10.3762/bjnano.10.92

• this, a transient photocurrent response measurement is employed to evaluate the charge migration and separation efficiency of the as-obtained photocatalysts. Transient photocurrents of g-C3N4, CCN and CISCCN3 are studied during the on–off cycles with intermittent exposure of visible-light excitation

• (Figure 10). Evidently, the as-prepared CCN and CISCCN3 samples display a distinct increase of photocurrent intensity in comparison with single CCN, demonstrating that C-doping as well as the close heterogeneous junction formed between CdIn2S4 and CCN can facilitate the separation of photogenerated

• electrons and holes, which ultimately endows the CISCCN3 composites with the enhanced photocatalytic performance. This photocurrent result corroborates the results from the UV–vis DRS and PL experiments, as well as the photocatalytic performance. Photocatalytic mechanism Figure 11a displays the specific

Geometrical optimisation of core–shell nanowire arrays for enhanced absorption in thin crystalline silicon heterojunction solar cells

• Robin Vismara,
• Olindo Isabella,
• Andrea Ingenito,
• Fai Tong Si and
• Miro Zeman

Beilstein J. Nanotechnol. 2019, 10, 322–331, doi:10.3762/bjnano.10.31

• solar cell. Implied photocurrent densities close to 27 mAcm−2 are achieved, for a 2 μm thick c-Si absorber coated with nanowires. The enhanced optical performance, with respect to a flat device, is explained by excitation of resonances both inside the nanowires and in the bulk c-Si absorber. In addition

• , good angular resilience is displayed, with high implied photocurrent density values (i.e., strong absorption) observed for angles of incidence of light up to 60°, making the proposed solar cell architecture attractive in a wide range of illumination conditions. Experimental Device manufacturing and

• structure were used. Simulation results consists of reflection (R) and absorption (Ai) in each layer (i) of the model, as functions of the wavelength of the incident light. A convolution of the obtained spectral data with the AM1.5 photon flux results in the implied photocurrent density (Jph,i) generated

Uniform Sb₂S₃ optical coatings by chemical spray method

• Jako S. Eensalu,
• Atanas Katerski,
• Erki Kärber,
• Ilona Oja Acik,
• Arvo Mere and
• Malle Krunks

Beilstein J. Nanotechnol. 2019, 10, 198–210, doi:10.3762/bjnano.10.18

• ]. Improvements in photocurrent density have been sought by utilizing a transparent, nanostructured window layer instead of planar window layers with the ETA Sb2S3 absorber layer [4][7]. Previous studies show that achieving sufficient repeatability alongside optimization of the component layers, i.e., transparent

Near-infrared light harvesting of upconverting NaYF₄:Yb³⁺/Er³⁺-based amorphous silicon solar cells investigated by an optical filter

• Daiming Liu,
• Qingkang Wang and
• Qing Wang

Beilstein J. Nanotechnol. 2018, 9, 2788–2793, doi:10.3762/bjnano.9.260

• -fold to 72-fold improvement of the photocurrent under 980 nm laser light [13]. An enhancement of 10 mA/cm2 in a NaYF4:Yb/Er-based a-Si:H cell was measured under illumination with a 980 nm diode laser (10 mW) [14]. The usage of laser undoubtedly enhances the illumination intensity and thus magnifies the

• point (0.45 V, 12.45 mA). The inset shows a photograph with the active area of ca. 0.84 cm2. The external quantum efficiency (EQE) curve in Figure 3c reveals that almost no photocurrent is generated when the wavelength of light is longer than 800 nm. The transmittance spectrum of a-Si:H solar cell

• layer to increase the photocurrent and EQE. Light scattering occurs on an object when its size is comparable to the wavelength of light [18]. Because the nanorods are comparable in size to the incident wavelength, they effectively scatter the upconverted and/or the incoming visible light, as illustrated

Impact of the anodization time on the photocatalytic activity of TiO₂ nanotubes

• Jesús A. Díaz-Real,
• Geyla C. Dubed-Bandomo,
• Juan Galindo-de-la-Rosa,
• Luis G. Arriaga,
• Janet Ledesma-García and
• Nicolas Alonso-Vante

Beilstein J. Nanotechnol. 2018, 9, 2628–2643, doi:10.3762/bjnano.9.244

• annealing conditions. An interesting remark from the literature comes from Hardcastle et al. [53] who observed that anodically grown TNTs after heat treatment between 400 and 500° C showed a 6.5-fold increase in the photocurrent density when the crystalline phase changed in proportion from 72% anatase (400

• of their specific systems [27][60][61]. A similar approach was used to evaluate the PEC properties of the TNTs. For this purpose, the electrodes were illuminated in a cell with quartz window while performing LSV using the same pretreatment of 10 s polarization. The photocurrent, jph, is then obtained

• potential when molecular species are present. To evaluate the oxidative contribution of the photogenerated holes, methanol (MeOH) was added to the electrolyte. From Figure 6c it can be seen that the addition of 0.5 M MeOH increases the photocurrent jph up to 200% (Figure 6a). This refers to a phenomenon

Thickness-dependent photoelectrochemical properties of a semitransparent Co₃O₄ photocathode

• Malkeshkumar Patel and
• Joondong Kim

Beilstein J. Nanotechnol. 2018, 9, 2432–2442, doi:10.3762/bjnano.9.228

• Co3O4 samples, which exhibit light-induced photocurrent in photoelectrochemical cells (PEC) containing the alkaline electrolyte. The thickness-dependent properties of Co3O4 related to its use as a working electrode in PEC cells are extensively studied and show potential for the application in water

• ]. Existing studies have measured a photocurrent of 33.6 μA·cm−2 in 0.5 M Na2S on a mesoporous Co3O4 nanosheet grown through in situ transformation from hexagonal Co(OH)2 to spinel Co3O4 [18]. Hong et al. demonstrated a photocurrent of 0.4 mA·cm−2 from Co3O4 nanowire photocathodes, which could be enhanced to

• 4.5 mA·cm−2 with Ag nanowires [24]. Interestingly, a high photocurrent density of 29 mA·cm−2 can be achieved from Co3O4 under one-sun illumination (AM1.5G) suggesting a high (solar-to-hydrogen) efficiency of 35.8% [3]. Studies using Co3O4 as a catalyst have explored the oxygen evolution reaction (OER

Performance analysis of rigorous coupled-wave analysis and its integration in a coupled modeling approach for optical simulation of complete heterojunction silicon solar cells

• Ziga Lokar,
• Benjamin Lipovsek,
• Marko Topic and
• Janez Krc

Beilstein J. Nanotechnol. 2018, 9, 2315–2329, doi:10.3762/bjnano.9.216

• transferred into photocurrent. Thus, these are the maximal potential gains related to the given PF variation. As a reference (zero gain) the structure with PF 0.7 was taken. In Figure 7a the reflectance curves are shown for the case of normal incident light. As a reference, the reflectance curve corresponding

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

Beilstein J. Nanotechnol. 2018, 9, 2209–2235, doi:10.3762/bjnano.9.207

• typically used as a solvent for the spin-coating deposition of MABI layers [160]. NMP slows the HP crystallization favoring the formation of a more uniform MABI layer and providing a ≈50% enhancement of the photocurrent generation efficiency. Simultaneously, the optimized morphology shows an enhanced

• characteristic Urbach energy of ≈60 meV, indicating a substantial level of structural and energetic disorder. Due to the disorder, planar inverted solar cells based on amorphous MA3Sb2I9 showed low photocurrent densities, however, with a relatively high open-circuit voltage (≈890 meV) and a decent fill factor

Spin-coated planar Sb₂S₃ hybrid solar cells approaching 5% efficiency

• Pascal Kaienburg,
• Benjamin Klingebiel and
• Thomas Kirchartz

Beilstein J. Nanotechnol. 2018, 9, 2114–2124, doi:10.3762/bjnano.9.200

• infiltration of pores [22], which can give way to incomplete coverage of the TiO2 scaffold and an interface between TiO2 and HTM. From a conceptual perspective, planar geometries reduce the large interface area required in ETA cells for appreciable photocurrent generation and should better prevent direct

• ][61][62]. Photons that are absorbed by the polymer generate excitons that can only diffuse up to around 10 nm before they recombine. While a photocurrent contribution from the polymer was demonstrated for certain Sb2S3 ETA cells [29] where the interface area is large and close-by, absorption in planar

• transmitted to the metal back contact where it is reflected back through the P3HT into the Sb2S3 absorber where it contributes to the photocurrent. The decreased parasitic absorption above 650 nm causes a maximum in the EQE at roughly that wavelength. KP115 on the other hand still absorbs at 650 nm so that

Localized photodeposition of catalysts using nanophotonic resonances in silicon photocathodes

• Evgenia Kontoleta,
• Sven H. C. Askes,
• Lai-Hung Lai and
• Erik C. Garnett

Beilstein J. Nanotechnol. 2018, 9, 2097–2105, doi:10.3762/bjnano.9.198

• corresponding photocurrent (Figure S4a, Supporting Information File 1), which means that the electrons reaching the electrolyte by biasing the samples dominate over the photogenerated ones. SEM images (Figure S5, Supporting Information File 1) show the homogenous formation of platinum nanoparticles both on the

A scanning probe microscopy study of nanostructured TiO₂/poly(3-hexylthiophene) hybrid heterojunctions for photovoltaic applications

• Laurie Letertre,
• Roland Roche,
• Olivier Douhéret,
• Hailu G. Kassa,
• Denis Mariolle,
• Nicolas Chevalier,
• Łukasz Borowik,
• Philippe Dumas,
• Benjamin Grévin,
• Roberto Lazzaroni and
• Philippe Leclère

Beilstein J. Nanotechnol. 2018, 9, 2087–2096, doi:10.3762/bjnano.9.197

• was observed as a result of the accumulation of photogenerated holes in the P3HT layer. A positive photocurrent was recorded in PC-AFM measurements, whose spatial mapping was interpreted consistently with the corresponding KPFM analysis, offering a correlated analysis of interest from both a

• literature regarding the photovoltaic response of TiO2/P3HT blends [16][17][18][19][20][21][22][23] and can be used as a reference for meaningful interpretations of our measurements, both in terms of photocurrent and photovoltage under illumination. The columnar TiO2/P3HT-COOH HHJs have been studied by

• photoconductive-AFM (PC-AFM) and photo-assisted Kelvin probe force microscopy (photo-KPFM) to follow the photovoltaic response, i.e., photocurrent and photovoltage, respectively, at the nanoscale under illumination, in order to understand the local physical processes taking place during the photoconversion of

Direct AFM-based nanoscale mapping and tomography of open-circuit voltages for photovoltaics

• Katherine Atamanuk,
• Justin Luria and
• Bryan D. Huey

Beilstein J. Nanotechnol. 2018, 9, 1802–1808, doi:10.3762/bjnano.9.171

• , local photovoltaic (PV) properties such as the open-circuit voltage, photocurrent, and work function have been demonstrated to vary by an order of magnitude, or more, within tens of nanometers [1][2][3]. Recently, property mapping with high spatial resolution by AFM has been further combined with the

• -circuit current (ISC) can then be directly visualized by simply measuring the photocurrent when there is no potential difference between the sample and the scanning probe. By further sweeping the bias between the sample and the grounded tip, for a single spot or an array of locations, the resulting I–V

• curves can be analyzed to interpret several additional performance metrics, which are widely employed by the PV and solar power communities. The open-circuit voltage (VOC), for example, is the probe bias necessary for the photocurrent to pass from positive to negative values, i.e. when the solar cell

Cr(VI) remediation from aqueous environment through modified-TiO₂-mediated photocatalytic reduction

• Rashmi Acharya,
• Brundabana Naik and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 1448–1470, doi:10.3762/bjnano.9.137

• ) curve (Figure 5) obtained from linear sweep voltammetry (LSV) gives the photocurrent generation by an applied bias; the higher the current density, the better the separation of photogenerated charge carriers [97][98]. It has been shown that a more negative open circuit potential (Voc), results in higher

• photoinduced charge carriers and shifts the absorption edge to the visible region by reducing the band gap of TiO2 [162][174]. The highest photoreduction efficiency of Cr(VI) was obtained with WO3/TiO2 NTs containing 1% tungsten (W) as it provides highest photocurrent and creates photogenerated carriers with

• photocurrent. Dozzi et al. synthesized a series of titanium–tungsten mixed oxides through coupling of TiO2 with varying WO3 percentage by a base-catalyzed sol–gel method [175]. WO3 plays a vital role in inhibiting charge recombination for efficient charge transfer to enhance the Cr(VI) reduction. Bi2O3

Semi-automatic spray pyrolysis deposition of thin, transparent, titania films as blocking layers for dye-sensitized and perovskite solar cells

• Hana Krýsová,
• Josef Krýsa and
• Ladislav Kavan

Beilstein J. Nanotechnol. 2018, 9, 1135–1145, doi:10.3762/bjnano.9.105

• . Without post-calcination at 500 °C, the photocurrent density is negligible. The photoresponse was similarly negligible for the deposition temperature of 300 °C (data not shown). Only after calcination at 500 °C will the low-temperature-grown films become photoactive, where the photocurrent onset was

• observed at around −0.35 V (Figure 1a). In the applied potential range of 0.25–1.2 V there is a photocurrent plateau at ≈14 μA/cm2 at the UV illumination intensity applied (7.5 mW/cm2). For the deposition temperature of 450 °C, our titania films are photoactive already in the as-grown state (see Figure 1b

• ). These TiO2 films exhibit the photocurrent onset at around –0.3 V but there is no plateau at larger potentials. Instead, the photocurrent increases monotonically with the applied potential. The effect of post-calcination is opposite compared to the low-temperature films deposited at 150 °C (cf. Figure 1a

Synthesis and characterization of two new TiO₂-containing benzothiazole-based imine composites for organic device applications

• Anna Różycka,
• Agnieszka Iwan,
• Krzysztof Artur Bogdanowicz,
• Michal Filapek,
• Natalia Górska,
• Damian Pociecha,
• Marek Malinowski,
• Patryk Fryń,
• Agnieszka Hreniak,
• Jakub Rysz,
• Paweł Dąbczyński and
• Monika Marzec

Beilstein J. Nanotechnol. 2018, 9, 721–739, doi:10.3762/bjnano.9.67

• , while for DSC studies, the mixture was scratched with a spatula and put into aluminum pans. Assembly and characterization of organic devices Samples for photocurrent measurements were prepared on ITO patterned glass substrates (Osilla S211) to form ITO/TiO2/SP1 (or SP1:P3HT, SP1:TiO2, SP1:PC71BM or P3HT

Facile synthesis of ZnFe₂O₄ photocatalysts for decolourization of organic dyes under solar irradiation

• Arjun Behera,
• Debasmita Kandi,
• Sanjit Manohar Majhi,
• Satyabadi Martha and
• Kulamani Parida

Beilstein J. Nanotechnol. 2018, 9, 436–446, doi:10.3762/bjnano.9.42

• , FESEM, UV–vis DRS, PL, FTIR and photocurrent measurements. The photocatalytic activity of the prepared material is studied with regard to the degradation of rhodamine B (Rh B) and Congo red under solar irradiation. The kinetic study showed that the material exhibits zeroth and first order reaction

• correlates well with the lowest PL intensity, highest photocurrent and lowest particle size. Keywords: Congo red; electrochemical study; phenol; photocatalyst; rhodamine B (Rh B); ZnFe2O4; Introduction Photocatalysis is a “green” technology for the treatment of environmental pollutants with solar energy [1

• –540 cm−1 is due to stretching vibrations of M–O bonds (Zn-O and Fe-O). Electrochemical studies Linear-sweep voltammetry In order to know the photocurrent response of the prepared catalysts, linear-sweep voltammetry was carried out in the range of 0–1.1 V in 0.1 M Na2SO4 at a scan rate of 10 mV·s−1