Comparison of organic and inorganic hole transport layers in double perovskite material-based solar cell

• Deepika K and
• Arjun Singh

Beilstein J. Nanotechnol. 2025, 16, 119–127, doi:10.3762/bjnano.16.11

• , that is, La2NiMnO6 (LNMO), is studied with the organic and inorganic hole transport layers (HTLs) Cu2O and PEDOT:PSS. Our study yields a significant improvement in the power conversion efficiency (PCE) of perovskite solar cells with two types of HTLs. The optimized devices achieved a maximum PCE of

• 27.84% and 27.38% for Cu2O and PEDOT:PSS, respectively, with corresponding open-circuit voltages of 1.27 and 1.22 V, short-circuit current densities of 28.60 and 28.91 mA/cm2, and fill factors of 76.31% and 77.15%, respectively. These results highlight the potential of these HTLs for enhanced device

• optimized PSC device displays a higher efficiency of 27.84% with Cu2O and 27.38% with PEDOT:PSS for the planar n-i-p FTO/WS2/LNMO/HTL/Au device structure. However, highly efficient organic HTLs have a few disadvantages over inorganic HTLs, including multistep synthesis requiring additional doping, leading

Modeling and simulation of carbon-nanocomposite-based gas sensors

• Roopa Hegde,
• Punya Prabha V,
• Shipra Upadhyay and
• Krishna S B

Beilstein J. Nanotechnol. 2025, 16, 90–96, doi:10.3762/bjnano.16.9

• sensor using COMSOL Multiphysics whose active sensing material used is a carbon nanocomposite (i.e., 0.1 wt % of single-walled carbon nanotubes along with PEDOT:PSS (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)) in an equal volume ratio of 1:1. Given the high cost associated with the

• using the nanocomposite materials which in turn enhances the sensitivity of the gas sensors. Keywords: CO gas; COMSOL Multiphysics; gas sensor; surface coverage; SWCNT/PEDOT:PSS; Introduction The field of nanotechnology has brought significant advancements in various scientific and engineering

• composed of PEDOT:PSS/poly(p-anisidine) (PPA) to detect CO was investigated at room temperature. The gas-sensing characteristics of the developed sensors such as sensitivity, response, and recovery time were evaluated at room temperature for different CO concentrations [5]. Many research works on PEDOT:PSS

CdSe/ZnS quantum dots as a booster in the active layer of distributed ternary organic photovoltaics

• Gabriela Lewińska,
• Piotr Jeleń,
• Zofia Kucia,
• Maciej Sitarz,
• Łukasz Walczak,
• Bartłomiej Szafraniak,
• Jerzy Sanetra and
• Konstanty W. Marszalek

Beilstein J. Nanotechnol. 2024, 15, 144–156, doi:10.3762/bjnano.15.14

• level. The energy gap was obtained from the Tauc diagram [57]. The levels correspond to a mixture of the levels obtained for pure CdSe and ZnS [58]. To evaluate the potential applicability of ternary mixtures, the volume heterojunctions of ITO/PEDOT:PSS/active layer/aluminum and ITO/active layer

• of QD-doped devices was compared to the reference system (ITO/PEDOT:PSS/P3HT:PCBM/aluminium). PEDOT:PSS ([poly(3.4-ethylene dioxythiophene] polystyrene sulfonate) is an intrinsically conductive polymer, a mixture of two ionomers, with a HOMO level equal to 5.17 eV [61]. It is widely used as a charge

• the reference cells (6 and 6′ devices in Table 5). The fill factor for all devices with QDs remained essentially unchanged. The original reference cell efficiency obtained for materials from the program database was 4.63% (with PEDOT:PSS) and −5.24% without PEDOT:PSS. The open-circuit voltage varies

Application of nanoarchitectonics in moist-electric generation

• Jia-Cheng Feng and
• Hong Xia

Beilstein J. Nanotechnol. 2022, 13, 1185–1200, doi:10.3762/bjnano.13.99

• humidification and dehumidification processes. (n) The equivalent circuit diagram of the PEDOT:PSS/PVDF double-layer generator charging a capacitor to power a LED. Figure 10k–n were reprinted from [92]. This article was published in Sensors and Actuators B: Chemical, vol. 255, by G. Wang; H. Xia; X.-C. Sun; C

Assessment of the optical and electrical properties of light-emitting diodes containing carbon-based nanostructures and plasmonic nanoparticles: a review

• Keshav Nagpal,
• Erwan Rauwel,
• Frédérique Ducroquet and
• Protima Rauwel

Beilstein J. Nanotechnol. 2021, 12, 1078–1092, doi:10.3762/bjnano.12.80

• HTL in OLED with the configuration ITO/PEDOT:PSS/SWNT–PVK nanocomposite/DCM-doped Alq3/Li:Al [47]. An efficient electron transport was also obtained from the Li:Al cathode (with work function of 2.9 eV) to the Alq3 layer due to its higher LUMO level (3.2 eV) in comparison to the Li:Al work function

• concentrations of MWNT were studied in PET/ITO/MWNT–PEDOT:PSS (80 nm)/Alq3/Al (40 nm) devices. At particular MWNT concentrations, higher current values (10 mA) and lower turn-on voltages (5 V) were noted. An optimal MWNT concentration of 0.6 wt % was deduced at which the EL intensity increased and the operating

• voltage decreased by a significant amount. However, a major concern regarding the reduction of the electron-blocking capability of PEDOT:PSS due to the addition of metallic MWNT needed further insight. Therefore, additional work by the same group [18] reported that the addition of MWNT in appropriate

Nanogenerator-based self-powered sensors for data collection

• Yicheng Shao,
• Maoliang Shen,
• Yuankai Zhou,
• Xin Cui,
• Lijie Li and
• Yan Zhang

Beilstein J. Nanotechnol. 2021, 12, 680–693, doi:10.3762/bjnano.12.54

• approximately 100%) TENG (WP-TENG) based on a poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) electrode and installed the WP-TENG-based self-powered motion sensor at different positions of a human arm. The WP-TENG was placed on the skin above the muscles of the arm, as shown in Figure 2a

• 2016 American Chemical Society. Figure 1b is adapted from [22]. Copyright © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Used with permission from Zhen Wen et al., “TA Wrinkled PEDOT:PSS Film Based Stretchable and Transparent Triboelectric Nanogenerator for Wearable Energy Harvesters and Active

Nickel nanoparticle-decorated reduced graphene oxide/WO₃ nanocomposite – a promising candidate for gas sensing

• Ilka Simon,
• Alexandr Savitsky,
• Rolf Mülhaupt,
• Vladimir Pankov and
• Christoph Janiak

Beilstein J. Nanotechnol. 2021, 12, 343–353, doi:10.3762/bjnano.12.28

• –air environment containing 10 ppm NO2 increased 1.6-fold (from 17.6 to 27.6 kΩ, Figure 6 left). Figure 6 (right) shows a sensor response curve for a sample that is a composite layer of Ni@rGO in the conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). This layer is

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

• same features as the raw data however at a slightly lower noise level. Organic BHJ thin films processing, solar cell fabrication and characterization The PTB7:PC71BM BHJ thin film was deposited on an indium thin oxide (ITO) substrate coated with PEDOT:PSS (a hole-conducting polymer) following the

• procedure published by Liang et al. [28]. PTB7 (Ossila, Mw = 85 kDa, PDI = 2.0) and PC71BM (Solenne BV, 99% purity) were used as received. A thin layer of filtered (0.45 µm) PEDOT:PSS (Baytron A14083, Clevios) was spin-coated onto the activated ITO surface at 5000 rpm for 25 s, 4000 rpm for 60 s and 4000

• levels of holes and electrons upon illumination, symbolized by dotted lines. (b) Organic BHJ solar cell and experimental configuration. The sample is illuminated in backside geometry. The transparent anode, the hole collecting electrode made of indium tin oxide coated with PEDOT:PSS, is grounded. The

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

• of these NCs incorporated into the PTB7:PC71BM active layer of bulk-heterojunction ternary organic photovoltaic (OPV) cells. The OPV devices are fabricated with the direct configuration glass/ITO/PEDOT:PSS/PTB7:PC71BM:FeS2/PFN/FM. The Field’s metal (FM) is a eutectic alloy composed of 32.5% Bi, 51

• temperatures. In this work, semispherical pyrite NCs are synthesized and added at different concentrations as second electron acceptors into the PTB7:PC71BM active layer of the OPVs that are fabricated with the direct configuration glass/ITO/PEDOT:PSS/PTB7:PC71BM:FeS2/PFN/FM, where PFN is poly[(9,9-bis(3'-(N,N

• OPV layers cross-section. We observe thicknesses of each layer that acceptably correlate with the sheet thicknesses determined by the AFM measurement in contact mode, namely ITO ≈197 nm, PEDOT:PSS ≈40 nm and PTB7:PC71BM active layer ≈113 nm. Figure S3(a–d) in Supporting Information File 1 shows the

Widening of the electroactivity potential range by composite formation – capacitive properties of TiO₂/BiVO₄/PEDOT:PSS electrodes in contact with an aqueous electrolyte

• Konrad Trzciński,
• Mariusz Szkoda,
• Andrzej P. Nowak,
• Marcin Łapiński and
• Anna Lisowska-Oleksiak

Beilstein J. Nanotechnol. 2019, 10, 483–493, doi:10.3762/bjnano.10.49

• vanadate using pulsed laser deposition. The formation of the TiO2/BiVO4 junction leads to enhancement of pseudocapacitance in the cathodic potential range. The third component, the conjugated polymer PEDOT:PSS, was electrodeposited from an electrolyte containing the monomer EDOT and NaPSS as a source of

• . Capacitance values higher than 10 mF·cm−2 were maintained even after 10000 galvanostatic cycles (ic = ia = 0.5 mA·cm−2). Keywords: bismuth vanadate (BiVO4); electrochemical activity; PEDOT:PSS; supercapacitors; titania nanotubes; Introduction Energy-storage technologies and sustainable energy production are

• [27][28], but in the present work, we utilized an electrochemical method. The last modification step of the TiO2/BiVO4 electrode the electrodeposition of PEDOT:PSS from an electrolyte containing the monomer EDOT and NaPSS as a source of counter ions. This procedure was expected to extend the

Lead-free hybrid perovskites for photovoltaics

• Oleksandr Stroyuk

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

• dominates in the studies of HPs with the typical ETLs being titania and various TiO2-based composites [27]. The most efficient and frequently used HTLs are among the derivatives of spirobifluorene (Spiro-OMeTAD, see Table 1) and polythiophenes (PEDOT:PSS). Recently, very good prospects were recognized for

• open-circuit voltage of up to 1.19 V and fill factor (FF) of almost 90% when introduced into inverted solar cells with PEDOT:PSS and PCBM charge transport layers [101]. Despite the high Voc and FF values, the cells showed quite a low efficiency of ≈0.3% indicating huge recombinational losses and

• °C provided that a portion of SbI3 lost during the heating due to a high SbI3 vapor pressure at the annealing temperature is compensated [89]. A comparative study of inverted solar cells composed of 2D- and 0D-Cs3Sb2I9 (produced at 150 °C), a PEDOT:PSS HTL and a PC70BM ETL resulted in PCEs of 1.5

Optimisation of purification techniques for the preparation of large-volume aqueous solar nanoparticle inks for organic photovoltaics

• Furqan Almyahi,
• Thomas R. Andersen,
• Nathan A. Cooling,
• Natalie P. Holmes,
• Matthew J. Griffith,
• Krishna Feron,
• Xiaojing Zhou,
• Warwick J. Belcher and
• Paul C. Dastoor

Beilstein J. Nanotechnol. 2018, 9, 649–659, doi:10.3762/bjnano.9.60

• efficiency of NP-OPV devices can be attributed to improved wetting properties between ASNP inks and the underlying PEDOT:PSS layer. The efficiency drop observed at higher surface tensions are ascribed to a reduction in the ink wetting properties as observed in Supporting Information File 1, Figure S2 and

• -scale devices prepared by spin-coating to large area R2R prepared devices. We have chosen to utilize HTL Solar as our PEDOT:PSS for this study as it has a PEDOT to PSS ratio of 1:2.5 which is the same as PH1000 which are being used frequently for R2R prepared large area devices [16][25][26][27

• ) with 98% purity was purchased from Sigma-Aldrich. Poly(ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) Clevios HTL Solar was purchased from Heraeus. For the ultrafiltration process, centrifugal filter tubes (for small-volume) and Vivaflow 200 crossflow cassette (for large-volume) were

The role of ligands in coinage-metal nanoparticles for electronics

• Ioannis Kanelidis and
• Tobias Kraus

Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263

• plates (600 nm in length and 30 nm in thickness) or spheres and rods (5 μm in length and 100 nm in diameter) led to layers with conductivities of 14706 and 31250 S/cm already at 62 and 54% metal mass fraction, respectively [74]. Similarly, gold nanorods in composites with PEDOT:PSS yielded films that had

• higher conductivities than films filled with spheres. Both rods and spheres were capped with PEG-SH (Figure 2), a non-conductive ligand that was chosen because ethylene glycol (EG) is miscible with aqueous PEDOT:PSS solutions and the addition of EG to pure PEDOT:PSS films increases the electrical

• spherical and rod-like gold nanoparticles dispersed in a formulation with PEDOT:PSS. Composite films with nanorod volume fractions between 10 and 70% were deposited onto quartz substrates; the film with the highest metal content reached a conductivity of 2000 S/cm without further processing, approximately

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• nacre-mimetics by designing an optically transparent and electron conductive coating based on PEDOT:PSS and nanoclays Laponite RD and Cloisite Na+. We carry out extensive characterization of the nanocomposite using transmittance spectra (transparency), conductive atomic force microscopy (conductivity

• leverage the brick-and-mortar structure and properties, in combination with a variety of atomic force microscopy (AFM) methods, to investigate the high-pressure response of a bioinspired transparent and electrically conductive nanocomposite. Specifically, a transparent PEDOT:PSS/nanoclay coating is

• PEDOT:PSS is a highly conductive polymer that can be designed to have high optical transparency [29]. In “thick” PEDOT:PSS films, the blue color of PEDOT dominates the optical properties [30]. Thickness reduction is customary in order to achieve highly transparent films. Conductive and transparent

Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy

• Hanaul Noh,
• Alfredo J. Diaz and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 579–589, doi:10.3762/bjnano.8.62

• typical energy levels of PCDTBT, PCBM and PEDOT:PSS were used to draw the energy diagrams in Figure 5b–d. Since the tip is exposed to air, we used 4.25 eV for the work function of platinum [30]. Because the tip diameter is several times smaller than the thickness of the active layer, the electric field is

• energy level of either the lowest unoccupied molecular orbital (LUMO) or the highest occupied molecular orbital (HOMO) of PCDTBT and PCBM, and E is the biased Fermi energy of either the electron or hole at the Pt tip and the PEDOT:PSS. Since the measured currents in C-AFM are related to the transmission

• prepared. Device fabrication Clean ITO-coated glass substrates (Sigma-Aldrich, 703192) were prepared by sonication with isopropyl alcohol and deionized water for 10 min, sequentially. A conductive polymer layer using high-conductivity grade 1.0 wt % in H2O PEDOT:PSS as received (Sigma-Aldrich, 768642) was

Reorientation of single-wall carbon nanotubes in negative anisotropy liquid crystals by an electric field

• Amanda García-García,
• Ricardo Vergaz,
• José F. Algorri,
• Gianluigi Zito,
• Teresa Cacace,
• Antigone Marino,
• José M. Otón and
• Morten A. Geday

Beilstein J. Nanotechnol. 2016, 7, 825–833, doi:10.3762/bjnano.7.74

• resistivity of 100 Ω/□ and separated by 8.25 µm. The active area was 1 cm2. A LC planar alignment is induced by poly(3,4-ethylenedioxythiophene) and poly(styrenesulfonate) (PEDOT:PSS, Sigma-Aldrich). The PEDOT solution (1.3 wt % in water) was spin-coated at 1600 rpm and buffed. Polyimides and polymers

• typically form the alignment layer to promote the planar orientation in the LC devices. Their use is not suitable for the impedance measurements because they provide insulation layers. PEDOT:PSS induces the planar alignment layer and is a conducting polymer, which is essential to keep electric continuity

High-resolution noncontact AFM and Kelvin probe force microscopy investigations of self-assembled photovoltaic donor–acceptor dyads

• Benjamin Grévin,
• Pierre-Olivier Schwartz,
• Laure Biniek,
• Martin Brinkmann,
• Nicolas Leclerc,
• Elena Zaborova and
• Stéphane Méry

Beilstein J. Nanotechnol. 2016, 7, 799–808, doi:10.3762/bjnano.7.71

• ± 5 nm thick, determined from intermittent-contact AFM measurements, not shown) were deposited from toluene solutions (10 mg/mL) via spin-coating on indium–tin–oxide (ITO) functionalized with PEDOT:PSS (thickness 40 ± 5 nm). In this study, PEDOT:PSS was primarily used to reduce the roughness of the

• only from the interface dipole at the recessed dyad–PEDOT:PSS interface. In turn, the KPFM potential displays modulations over the edge-on domains, in correspondence with the topography and damping channels (see Figure S2 in Supporting Information File 1). Moreover, the KPFM potential image shows

• the film surface. Geometry of the experimental setup for KPFM. The sample is illuminated in backside geometry. The modulation and compensation bias are applied to the tip, while the ITO substrate is grounded. (a) nc-AFM topographic image (500 × 500 nm) of the AD1 film on ITO/PEDOT:PSS (Δf = −55 Hz

Nanoscale effects in the characterization of viscoelastic materials with atomic force microscopy: coupling of a quasi-three-dimensional standard linear solid model with in-plane surface interactions

• Santiago D. Solares

Beilstein J. Nanotechnol. 2016, 7, 554–571, doi:10.3762/bjnano.7.49

Simple approach for the fabrication of PEDOT-coated Si nanowires

• Mingxuan Zhu,
• Marielle Eyraud,
• Judikael Le Rouzo,
• Nadia Ait Ahmed,
• Florence Boulc’h,
• Claude Alfonso,
• Philippe Knauth and
• François Flory

Beilstein J. Nanotechnol. 2015, 6, 640–650, doi:10.3762/bjnano.6.65

• heterojunction showed rectification behavior with a large saturation current density. A relatively low shunt resistance and a high saturation current are displayed by devices produced using the spin coating method. This is because the PEDOT:PSS only partially covers the SiNWs array, leaving most of the SiNW

Electrical response of liquid crystal cells doped with multi-walled carbon nanotubes

• Amanda García-García,
• Ricardo Vergaz,
• José F. Algorri,
• Xabier Quintana and
• José M. Otón

Beilstein J. Nanotechnol. 2015, 6, 396–403, doi:10.3762/bjnano.6.39

• consistent with a possible electric contact between the coated substrates of the LC cell caused by the reorientation of the nanotubes. The reversibility of the doped system upon removal of the electric field is quite low. Keywords: carbon nanotubes; Cole–Cole diagrams; impedance; liquid crystal; PEDOT:PSS

• electrode plates at the off-state. The planar LC alignment was induced by PEDOT:PSS [poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate)]. A 1.3 wt % solution of PEDOT:PSS in water (Sigma-Aldrich) was spin-coated onto the plates and eventually buffed with a velvet cloth to induce a specific planar

• efficient aligning surface, PEDOT:PSS has a remarkably higher conductivity than polyimide, what is essential to keep electric continuity across the layer. Characterization method: driving waveform Impedance spectroscopy customarily employs sufficiently small voltage signals so that the system response is

Carbon nano-onions (multi-layer fullerenes): chemistry and applications

• Juergen Bartelmess and
• Silvia Giordani

Beilstein J. Nanotechnol. 2014, 5, 1980–1998, doi:10.3762/bjnano.5.207

• (styrenesulfonate) (PEDOT:PSS) [47]. In a very recent study, they reported the non-covalent functionalization of CNOs with poly(4-vinylpyridine-co-styrene) (PVPS) and poly(ethylene glycol)/Polysorbate 20 (PEG/P20) [48]. The PVPS polymers were then further functionalized with thiols. Both CNO-containing polymers

• supercapacitor electrodes [46]. Also the CNO/PEDOT:PSS composites, which were previously discussed, showed promising properties for the application as electrode material in supercapacitors, such as a specific capacity of 96 F·g−1, good cation-exchange properties and a simple synthesis [47]. In a recent study

An insight into the mechanism of charge-transfer of hybrid polymer:ternary/quaternary chalcopyrite colloidal nanocrystals

• Parul Chawla,
• Son Singh and
• Shailesh Narain Sharma

Beilstein J. Nanotechnol. 2014, 5, 1235–1244, doi:10.3762/bjnano.5.137

• (3,4-ethylenedioxioxythiophene):poly(4-styrenesulfonate) complex (PEDOT:PSS) [11][12]. Recently, nanocrystals of one of the well-known quarternary chalcopyrite copper-zinc-tin-selenide (CZTSe) has been receiving considerable attention as a promising candidate for low-cost active absorber layers as it

Optimization of solution-processed oligothiophene:fullerene based organic solar cells by using solvent additives

• Gisela L. Schulz,
• Marta Urdanpilleta,
• Roland Fitzner,
• Eduard Brier,
• Elena Mena-Osteritz,
• Egon Reinold and
• Peter Bäuerle

Beilstein J. Nanotechnol. 2013, 4, 680–689, doi:10.3762/bjnano.4.77

• to energy levels of three different electron-accepting fullerene derivatives used in the various experiments. Solar cell devices were fabricated by spin-coating the DCV5T-Bu4:PCBM blend from hot solutions at 80 °C on ITO|PEDOT:PSS-coated substrates, which were heated to 90 °C. Subsequently 1 nm LiF

• using atomic force microscopy (AFM). The samples were prepared in the same way as the photoactive layers for the solar cell devices; by spin-coating the DCV5T-Bu4:PCBM blends from hot solutions at 80 °C on ITO|PEDOT:PSS-coated substrates heated to 90 °C. Figure 6 depicts the phase images of DCV5T-Bu4

• higher boiling point than CB (259 vs 132 °C), upon evaporation of CB during the final spin-coating stage, the CN content near the substrate increases. Considering the higher solubility of the oligothiophene in CN, we suggest that DCV5T-Bu4-richer domains are formed at the PEDOT:PSS interface. This

Low-temperature synthesis of carbon nanotubes on indium tin oxide electrodes for organic solar cells

• Andrea Capasso,
• Luigi Salamandra,
• Aldo Di Carlo,
• John M. Bell and
• Nunzio Motta

Beilstein J. Nanotechnol. 2012, 3, 524–532, doi:10.3762/bjnano.3.60

• states of ITO–CNT lying lower than those of ITO. A similar kind of band alignment is almost achieved in the standard cell architecture by the insertion of a layer of poly(3,4-ethylene dioxythiophene):(polystyrene sulfonic acid) (PEDOT:PSS). This polymer is used to improve the contact (and reduce the

• mismatch in energy level) between the ITO and the P3HT, although it is also known to shorten the device lifetime [33]. Being slightly acidic, the PEDOT:PSS is in fact able to etch the ITO and causes interface instability through indium diffusion into the polymer active layer. In our case instead, we

• comparison with the data obtained for a reference cell made with a standard ITO-coated glass anode (i.e., without the addition of PEDOT:PSS). The I–V characteristic of a standard ITO/PEDOT:PSS/P3HT:PCBM/Al cell is also reported in Figure 5b, for a full understanding of the experimental results. All the