High efficiency stable inverted perovskite solar cells without current hysteresis

Wu, Chun‐Guey; Chiang, Chien‐Hung; Tseng, Zong‐Liang; Nazeeruddin, Md. K.; Hagfeldt, Anders; Grätzel, Michaël

doi:10.1039/c5ee00645g

Cited by 547 publications

(412 citation statements)

References 48 publications

Supporting

Mentioning

390

Contrasting

Unclassified

Order By: Relevance

“…[30] Especially, for the low-bandgap perovskite (60% and 80% Sn content) based PV devices, the obtained V OC 's are significantly high given the fact that planar heterojunction-based PV device configuration is generally known to demonstrate low V OC 's in comparison with device architectures incorporating mesoporous charge extraction layers. [35,48,49] The EQEs measured for these devices are lower at higher wavelengths due to lower absorption in the IR absorption compared to that in the visible region (see the Supporting Information, Figure S1) and this could potentially limit the J SC 's that we get in our devices. This problem has been attributed to the presence of MAPb x Sn 1-x Cl 3 up to 33% of the total material in the thin film that does not absorb visible light due to its large bandgap (>3 eV), [50] and the longer wavelength absorption and EQE can be increased by adding molecular iodine into the precursor solution that reduces this pure chloride perovskite phase to below 10%, hence, enhancing the longer Adv.…”

Section: Doi: 101002/adma201604744mentioning

confidence: 99%

High Open‐Circuit Voltages in Tin‐Rich Low‐Bandgap Perovskite‐Based Planar Heterojunction Photovoltaics

et al. 2016

View full text Add to dashboard Cite

] Of relevance to this work is the binary metal perovskite CH 3 NH 3 (Pb x Sn 1-x )I 3 [0 ≤ x ≤ 1]. [30,31] Interestingly, the bandgap bows and becomes lower when Sn 2+ is substituted by Pb 2+ for samples with 80% and 60% Sn content compared to 100% Sn-based perovskite, in line with previous observations. [30,31] While such tin-based perovskites offer tunable bandgaps down to 1.1 eV, the fabrication of efficient optoelectronic devices has been impeded by factors including poor semiconductor quality and low surface coverage. [30] As a consequence, solar cells made using these perovskites often exhibit very low efficiencies, with typical PCEs < 1% obtained for planar heterojunction devices. [30] To overcome this challenge, we have developed a novel elevated temperature processing method (depicted in Figure 1A), [32] for preparing CH 3 NH 3 (Pb x Sn 1-x )I 3 perovskites on a Poly(3,4-ethylenedioxythiophene):poly(styrenesulf onate) (PEDOT:PSS)/nickel oxide (NiO) bilayer, which results in the formation of large micron-sized grains ( Figure 1B) with almost complete substrate coverage. Our semiconductors not only exhibit relatively low energetic and structural disorder but also impart high PCEs when fabricated into a PV device. For PVs prepared using the lowest bandgap perovskites, open circuit voltages (V OC 's) approaching the prediction of the Shockley-Queisser (S-Q) model are demonstrated. Such promising performance metrics are obtained against a backdrop of fast radiative recombination and low photoluminescence quantum efficiencies (PLQEs), pointing toward the crucial role of high intrinsic charge carrier mobility in these low-bandgap semiconductors.To study the optical properties of the CH 3 NH 3 (Pb x Sn 1-x )I 3 [0 ≤ x ≤ 1] perovskite thin films, linear absorption and photoluminescence (PL) were measured as shown in Figure S1 (Supporting Information). It can be observed in Figure 1C that the bandgap bows as we substitute Pb 2+ in place of Sn 2+ (until 40% Sn 2+ ions are replaced by Pb 2+ ) and results in a nonmonotonic bandgap lowering similar to what was observed previously by Hao etal. [31] Briefly, the bandgap of the 60% and 80% Sn content films exhibit a lower bandgap than the 100% Sn-substituted films. A similar trend can also be traced in the PL spectra (see Figure S1B of the Supporting Information) where the PL spectra of 80% and 60% Sn content thin-film samples are red-shifted compared to the 100% Sn content thinfilm sample, which is consistent with the absorption spectra. Such anomalous bandgap bowing and lack of conformity with Vegard's law [31,33] have been attributed to the competition The performance of organometallic halide (hybrid) perovskite solar cells has improved dramatically in just a few years, with photovoltaic (PV) power conversion efficiencies (PCEs) now exceeding 22% for state-of-the-art devices. [1][2][3][4][5] This remarkable result, coupled with their low cost, tunability, and versatile lowtemperature preparation methods, makes hybrid perovskites one of the most promising semiconduct...

show abstract

Section: Doi: 101002/adma201604744mentioning

confidence: 99%

High Open‐Circuit Voltages in Tin‐Rich Low‐Bandgap Perovskite‐Based Planar Heterojunction Photovoltaics

et al. 2016

View full text Add to dashboard Cite

show abstract

“…[30,[33][34][35] In total, these studies show that it is feasible to unravel the mechanisms involved in perovskite film formation with GIXS techniques. However, in the case of 1-step methods, disentangling crystal formation mechanisms is complicated by the fact that processing parameters are influencing each other.…”

Section: Research Newsmentioning

confidence: 99%

Structure of Organometal Halide Perovskite Films as Determined with Grazing‐Incidence X‐Ray Scattering Methods

Schlipf

Müller‐Buschbaum

2017

Advanced Energy Materials

135

115

View full text Add to dashboard Cite

Grazing‐incidence X‐ray scattering (GIXS) methods have proven to be a valuable asset for investigating the morphology of thin films at different length scales. Consequently, GIXS has been applied to the fast‐progressing field of organometal halide perovskites. This exciting class of materials has propelled research in the areas of cheap and sustainable photovoltaics, light emitting devices, and optoelectronics in general. Especially, perovskite solar cells (PSC) have seen a remarkable rise in power conversion efficiencies, crossing the 20% mark after only five years of research. This research news outlines GIXS studies focusing on the most challenging research topics in the perovskite field today: Current–voltage hysteresis, device reproducibility, and long‐term stability of PSC are inherently linked to perovskite film morphology. On the other hand, film formation depends on the choice of precursors and processing parameters; understanding their interdependence opens possibilities to tailor film morphologies. Owing to their tunability and moisture resistance, 2D perovskites have recently attracted attention. Examples of GIXS studies with different measurement and data analysis techniques are presented, highlighting especially in‐situ investigations on the many kinetic processes involved. Thus, an overview on the toolbox of GIXS techniques is linked to the specific needs of research into organometal halide perovskite optoelectronics.

show abstract

“…[7][8][9][10] Especially the inverted structure has become an interesting solution as it is less prone to the detrimental J-V hysteresis and is also highly relevant for the tandem perovskite devices, 11,12 which is why we chose it in our study.…”

mentioning

confidence: 99%

Efficient Light Management by Textured Nanoimprinted Layers for Perovskite Solar Cells

et al. 2017

View full text Add to dashboard Cite

show abstract

High efficiency stable inverted perovskite solar cells without current hysteresis

Cited by 547 publications

References 48 publications

High Open‐Circuit Voltages in Tin‐Rich Low‐Bandgap Perovskite‐Based Planar Heterojunction Photovoltaics

High Open‐Circuit Voltages in Tin‐Rich Low‐Bandgap Perovskite‐Based Planar Heterojunction Photovoltaics

Structure of Organometal Halide Perovskite Films as Determined with Grazing‐Incidence X‐Ray Scattering Methods

Efficient Light Management by Textured Nanoimprinted Layers for Perovskite Solar Cells

Contact Info

Product

Resources

About