Query: perovskite solar cell snaith

Candidate papers:

abstract: Many different photovoltaic technologies are being developed for large scale solar energy conversion. The wafer based first generation photovoltaic devices have been followed by thin film solid semiconductor absorber layers sandwiched between two charge selective contacts and nanostructured (or mesostructured) solar cells that rely on a distributed heterojunction to generate charge and to transport positive and negative charges in spatially separated phases. Although many materials have been used in nanostructured devices, the goal of attaining high efficiency thin film solar cells in such a way has yet to be achieved. Organometal halide perovskites have recently emerged as a promising material for high efficiency nanostructured devices. Here we show that nanostructuring is not necessary to achieve high efficiencies with this material: a simple planar heterojunction solar cell incorporating vapour deposited perovskite as the absorbing layer can have solar to electrical power conversion efficiencies of over 15 per cent (as measured under simulated full sunlight) This demonstrates that perovskite absorbers can function at the highest efficiencies in simplified device architectures, without the need for complex nanostructures.
author_names: Mingzhen Liu

Michael B Johnston

Henry J Snaith
title: Efficient planar heterojunction perovskite solar cells by vapour deposition
venue: Nature
year: 2013

abstract: Stable perovskites with ionic salts Ionic liquids have been shown to stabilize organic inorganic perovskite solar cells with metal oxide carrier transport layers, but they are incompatible with more readily processible organic analogs. Lin et al. found that an ionic solid, a piperidinium salt, enhanced the efficiency of positive intrinsic negative layered perovskite solar cells with organic electron and hole extraction layers. Aggressive aging testing showed that this additive retarded segregation into impurity phases and pinhole formation in the perovskite layer. Science, this issue p. 96 An ionic compound additive improved perovskite solar cell longevity by inhibiting the generation of degradation products. Longevity has been a long standing concern for hybrid perovskite photovoltaics. We demonstrate high resilience positive intrinsic negative perovskite solar cells by incorporating a piperidinium based ionic compound into the formamidinium cesium lead trihalide perovskite absorber. With the bandgap tuned to be well suited for perovskite on silicon tandem cells, this piperidinium additive enhances the open circuit voltage and cell efficiency. This additive also retards compositional segregation into impurity phases and pinhole formation in the perovskite absorber layer during aggressive aging. Under full spectrum simulated sunlight in ambient atmosphere, our unencapsulated and encapsulated cells retain 80 and 95% of their peak and post burn in efficiencies for 1010 and 1200 hours at 60deg and 85degC, respectively. Our analysis reveals detailed degradation routes that contribute to the failure of aged cells.
author_names: Yen-Hung Lin

Nobuya Sakai

Peimei Da

Jiaying Wu

Harry C Sansom

Alexandra J Ramadan

Suhas Mahesh

Junliang Liu

Robert D J Oliver

Jongchul Lim

Lee Aspitarte

Kshama Sharma

P K Madhu

Anna B Morales-Vilches

Pabitra K Nayak

Sai Bai

Feng Gao

Chris R M Grovenor

Michael B Johnston

John G Labram

James R Durrant

James M Ball

Bernard Wenger

Bernd Stannowski

Henry J Snaith
title: A piperidinium salt stabilizes efficient metal halide perovskite solar cells
venue: Science
year: 2020

abstract: To date, the most efficient hybrid metal halide peroskite solar cells employ TiO2 as electron transporting material (ETM) making these devices unstable under UV light exposure. Replacing TiO2 with fullerene derivatives has been shown to result in improved electronic contact and increased device lifetime, making it of interest to assess whether similar improvements can be achieved by using other organic semiconductors as ETMs. In this work, we investigate perylene 3,4:9,10 tetracarboxylic bis(benzimidazole) as a vacuum processable ETM, and we minimize electron collection losses at the electron selective contact by depositing pentamethylcyclopentadienyl cyclopentadienyl rhodium dimer, (RhCp*Cp)2, on fluorinated tin oxide. With (RhCp*Cp)2 as an interlayer, ohmic contacts can be formed, there is interfacial doping of the ETM, and stabilized power conversion efficiencies of up to 14.2% are obtained.
author_names: Federico Pulvirenti

Berthold Wegner

Nakita K Noel

Giulio Mazzotta

Rebecca B M Hill

Jay B Patel

Laura M Herz

Michael B Johnston

Moritz K Riede

Henry J Snaith

Norbert Koch

Stephen Barlow

Seth R Marder
title: Modification of the fluorinated tin oxide/electron transporting material interface by a strong reductant and its effect on perovskite solar cell efficiency
year: 2018

abstract: Perovskites for tandem solar cells Improving the performance of conventional single crystalline silicon solar cells will help increase their adoption. The absorption of bluer light by an inexpensive overlying solar cell in a tandem arrangement would provide a step in the right direction by improving overall efficiency. Inorganic organic perovskite cells can be tuned to have an appropriate band gap, but these compositions are prone to decomposition. McMeekin et al. show that using cesium ions along with formamidinium cations in lead bromide iodide cells improved thermal and photostability. These improvements lead to high efficiency in single and tandem cells. Science, this issue p. 151 Addition of cesium cations creates a robust ideal inorganic organic perovskite absorber for tandem silicon solar cells. Metal halide perovskite photovoltaic cells could potentially boost the efficiency of commercial silicon photovoltaic modules from ~20 toward 30% when used in tandem architectures. An optimum perovskite cell optical band gap of ~1.75 electron volts (eV) can be achieved by varying halide composition, but to date, such materials have had poor photostability and thermal stability. Here we present a highly crystalline and compositionally photostable material, [HC(NH2)2]0.83Cs0.17Pb(I0.6Br0.4)3, with an optical band gap of ~1.74 eV, and we fabricated perovskite cells that reached open circuit voltages of 1.2 volts and power conversion efficiency of over 17% on small areas and 14.7% on 0.715 cm2 cells. By combining these perovskite cells with a 19% efficient silicon cell, we demonstrated the feasibility of achieving >25% efficient four terminal tandem cells.
author_names: David P McMeekin

Golnaz Sadoughi

Waqaas Rehman

Giles E Eperon

Michael Saliba

Maximilian T Horantner

Amir A Haghighirad

Nobuya Sakai

Lars Korte

Bernd Rech

Michael B Johnston

Laura M Herz

Henry J Snaith
title: A mixed cation lead mixed halide perovskite absorber for tandem solar cells
venue: Science
year: 2016

abstract: The vast majority of perovskite solar cell research has focused on organic inorganic lead trihalide perovskites. Herein, we present working inorganic CsPbI3 perovskite solar cells for the first time. CsPbI3 normally resides in a yellow non perovskite phase at room temperature, but by careful processing control and development of a low temperature phase transition route we have stabilised the material in the black perovskite phase at room temperature. As such, we have fabricated solar cell devices in a variety of architectures, with current voltage curve measured efficiency up to 2.9% for a planar heterojunction architecture, and stabilised power conversion efficiency of 1.7% The well functioning planar junction devices demonstrate long range electron and hole transport in this material. Importantly, this work identifies that the organic cation is not essential, but simply a convenience for forming lead triiodide perovskites with good photovoltaic properties. We additionally observe significant rate dependent current voltage hysteresis in CsPbI3 devices, despite the absence of the organic polar molecule previously thought to be a candidate for inducing hysteresis via ferroelectric polarisation. Due to its space group, CsPbI3 cannot be a ferroelectric material, and thus we can conclude that ferroelectricity is not required to explain current voltage hysteresis in perovskite solar cells. Our report of working inorganic perovskite solar cells paves the way for further developments likely to lead to much more thermally stable perovskite solar cells and other optoelectronic devices.
author_names: Giles E Eperon

Giuseppe Maria Paterno

Rebecca J Sutton

Andrea Zampetti

Amir A Haghighirad

Franco Cacialli

Henry J Snaith
title: Inorganic caesium lead iodide perovskite solar cells
year: 2015

abstract: Summary Multi junction device architectures can increase the power conversion efficiency (PCE) of photovoltaic (PV) cells beyond the single junction thermodynamic limit. However, these devices are challenging to produce by solution based methods, where dissolution of underlying layers is problematic. By employing a highly volatile acetonitrile(CH3CN)/methylamine(CH3NH2) (ACN/MA) solvent based perovskite solution, we demonstrate fully solution processed absorber, transport, and recombination layers for monolithic all perovskite tandem and triple junction solar cells. By combining FA0.83Cs0.17Pb(Br0.7I0.3)3 (1.94 eV) and MAPbI3 (1.57 eV) junctions, we reach two terminal tandem PCEs of more than 15% (steady state) We show that a MAPb0.75Sn0.25I3 (1.34 eV) narrow band gap perovskite can be processed via the ACN/MA solvent based system, demonstrating the first proof of concept, monolithic all perovskite triple junction solar cell with an open circuit voltage reaching 2.83 V. Through optical and electronic modeling, we estimate the achievable PCE of a state of the art triple junction device architecture to be 26.7% Our work opens new possibilities for large scale, low cost, printable perovskite multi junction solar cells.
author_names: David P McMeekin

Suhas Mahesh

Nakita K Noel

Matthew T Klug

Jongchul Lim

Jonathan H Warby

James M Ball

Laura M Herz

Michael B Johnston

Henry J Snaith
title: Solution Processed All Perovskite Multi junction Solar Cells
venue: Joule
year: 2019

abstract: Perovskite based solar cells have attracted significant recent interest, with power conversion efficiencies in excess of 15% already superceding a number of established thin film solar cell technologies. Most work has focused on a methylammonium lead trihalide perovskites, with a bandgaps of ~1.55 eV and greater. Here, we explore the effect of replacing the methylammonium cation in this perovskite, and show that with the slightly larger formamidinium cation, we can synthesise formamidinium lead trihalide perovskites with a bandgap tunable between 1.48 and 2.23 eV. We take the 1.48 eV bandgap perovskite as most suited for single junction solar cells, and demonstrate long range electron and hole diffusion lengths in this material, making it suitable for planar heterojunction solar cells. We fabricate such devices, and due to the reduced bandgap we achieve high short circuit currents of >23 mA cm 2, resulting in power conversion efficiencies of up to 14.2% the highest efficiency yet for solution processed planar heterojunction perovskite solar cells. Formamidinium lead triiodide is hence promising as a new candidate for this class of solar cell.
author_names: Giles E Eperon

Samuel D Stranks

Christopher Menelaou

Michael B Johnston

Laura M Herz

Henry J Snaith
title: Formamidinium lead trihalide: a broadly tunable perovskite for efficient planar heterojunction solar cells
year: 2014

abstract: In recent years, there has been an unprecedented rise in the performance of metal halide perovskite solar cells. They are now in a position to compete on performance with traditional crystalline solar cells, and as such the most pressing questions concern the long term operational stability of this class of solar cell. Here, recent developments in understanding and overcoming stability concerns of metal halide perovskite solar cells are highlighted. An overview of possible instability issues due to electrical, atmospheric, heat, and light stresses is provided and the different implications to the most commonly used device architectures are discussed.
author_names: T Leijtens

Giles E Eperon

Nakita K Noel

Severin N Habisreutinger

Annamaria Petrozza

Henry J Snaith
title: Stability of Metal Halide Perovskite Solar Cells
year: 2015

abstract: The ability to process amorphous or polycrystalline solar cells at low temperature <150 degC) opens many possibilities for substrate choice and monolithic multijunction solar cell fabrication. Organometal trihalide perovskite solar cells have evolved rapidly over the last two years, and the CH3NH3PbX3 (X Cl, I or Br) material is processed at low temperature. However the first embodiments of the solar cell were composed of high temperature processed (500 degC) compact and mesoporous layers of TiO2. The sintering of the mesoporous TiO2 has been negated by replacing this with a mesoporous insulating scaffold in the meso superstructured solar cell (MSSC) yet the high temperature processed compact TiO2 layer still persists in the most efficient devices. Here we have realised a low temperature route for compact TiO2, tailored for perovskite MSSC operation. With our optimized formulation we demonstrate full sun solar power conversion efficiencies of up to 15.9% in an all low temperature processed solar cell.
author_names: Konrad Wojciechowski

Michael Saliba

T Leijtens

Antonio Abate

Henry J Snaith
title: Sub 150 degC processed meso superstructured perovskite solar cells with enhanced efficiency
year: 2014

abstract: Metal halide perovskite semiconductors offer rapid, low cost deposition of solar cell active layers with a wide range of band gaps, making them ideal candidates for multijunction solar cells. Here, we combine optical and electrical models using experimental inputs to evaluate the feasible performances of all perovskite double junction (2PJ) triple junction (3PJ) and perovskite perovskite silicon triple junction (2PSJ) solar cells. Using parameters and design constraints from the current state of the art generation of perovskite solar cells, we find that 2PJs can feasibly approach 32% power conversion efficiency, 3PJs can reach 33% and 2PSJs can surpass 35% We also outline pathways to improve light harvesting and demonstrate that it is possible to raise the performances to 34% 37% and 39% for the three architectures. Additionally, we discuss important future directions of research. Finally, we perform energy yield modeling to demonstrate that the multijunction solar cells should not suffer from reduc.
author_names: Maximilian T Horantner

T Leijtens

Mark E Ziffer

Giles E Eperon

M Greyson Christoforo

Michael D McGehee

Henry J Snaith
title: The Potential of Multijunction Perovskite Solar Cells
year: 2017