33 results match your criteria Acs Energy Letters[Journal]

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Tuning the Excited-State Dynamics of CuI Films with Electrochemical Bias.

ACS Energy Lett 2019 Mar 13;4(3):702-708. Epub 2019 Feb 13.

Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, United States.

Owing to its high hole conductivity and ease of preparation, CuI was among the first inorganic hole-transporting materials that were introduced early on in metal halide perovskite solar cells, but its full potential as a semiconductor material is still to be realized. We have now performed ultrafast spectroelectrochemical experiments on ITO/CuI electrodes to show the effect of applied bias on the excited-state dynamics in CuI. Under operating conditions, the recombination of excitons is dependent on the applied bias, and it can be accelerated by decreasing the potential from +0. Read More

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http://dx.doi.org/10.1021/acsenergylett.9b00182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6413481PMC
March 2019
1 Read

Introductory Guide to Assembling and Operating Gas Diffusion Electrodes for Electrochemical CO Reduction.

ACS Energy Lett 2019 Mar 11;4(3):639-643. Epub 2019 Feb 11.

Materials for Energy Conversion and Storage, Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands.

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http://dx.doi.org/10.1021/acsenergylett.9b00137DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6413482PMC

Renewable Hydrogen and Electricity Dispatch with Multiple Ni-Fe Electrode Storage.

ACS Energy Lett 2019 Feb 30;4(2):567-571. Epub 2019 Jan 30.

Materials for Energy Conversion and Storage (MECS), Delft University of Technology, 2629 HZ Delft, Netherlands.

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http://dx.doi.org/10.1021/acsenergylett.8b02488DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6373986PMC
February 2019

Potassium- and Rubidium-Passivated Alloyed Perovskite Films: Optoelectronic Properties and Moisture Stability.

ACS Energy Lett 2018 Nov 28;3(11):2671-2678. Epub 2018 Sep 28.

Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge CB3 0HE, United Kingdom.

Halide perovskites passivated with potassium or rubidium show superior photovoltaic device performance compared to unpassivated samples. However, it is unclear which passivation route is more effective for film stability. Here, we directly compare the optoelectronic properties and stability of thin films when passivating triple-cation perovskite films with potassium or rubidium species. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b01504DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6344034PMC
November 2018
1 Read

Rationalizing and Controlling the Surface Structure and Electronic Passivation of Cesium Lead Halide Nanocrystals.

ACS Energy Lett 2019 Jan 27;4(1):63-74. Epub 2018 Nov 27.

Department of Theoretical Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.

Colloidal lead halide perovskite nanocrystals (NCs) have recently emerged as versatile photonic sources. Their processing and luminescent properties are challenged by the lability of their surfaces, i.e. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.8b01669
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http://dx.doi.org/10.1021/acsenergylett.8b01669DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6333230PMC
January 2019
10 Reads

Controlling the Phase Segregation in Mixed Halide Perovskites through Nanocrystal Size.

ACS Energy Lett 2019 Jan 27;4(1):54-62. Epub 2018 Nov 27.

Institute of Advanced Materials (INAM), University Jaume I, Avenida de Vicent Sos Baynat, s/n, 12006 Castelló de la Plana, Castellón, Spain.

Mixed halide perovskites are one of the promising candidates in developing solar cells and light-emitting diodes (LEDs), among other applications, because of their tunable optical properties. Nonetheless, photoinduced phase segregation, by formation of segregated Br-rich and I-rich domains, limits the overall applicability. We tracked the phase segregation with increasing crystalline size of CsPbBr I and their photoluminescence under continuous-wave laser irradiation (405 nm, 10 mW cm) and observed the occurrence of the phase segregation from the threshold size of 46 ± 7 nm. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b02207DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6333216PMC
January 2019

Spontaneous Silver Doping and Surface Passivation of CsPbI Perovskite Active Layer Enable Light-Emitting Devices with an External Quantum Efficiency of 11.2.

ACS Energy Lett 2018 Jul 13;3(7):1571-1577. Epub 2018 Jun 13.

Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP), City University of Hong Kong, Kowloon, Hong Kong SAR.

Lead halide perovskite nanocrystals are currently under intense investigation as components of solution-processed light-emitting devices (LEDs). We demonstrate LEDs based on Ag doped-passivated CsPbI perovskite nanocrystals with external quantum efficiency of 11.2% and an improved stability. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.8b00835
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http://dx.doi.org/10.1021/acsenergylett.8b00835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6269143PMC
July 2018
27 Reads

Ultrafast Intraband Spectroscopy of Hot-Carrier Cooling in Lead-Halide Perovskites.

ACS Energy Lett 2018 Sep 21;3(9):2199-2205. Epub 2018 Aug 21.

Department of Chemistry, Imperial College London, London SW7 2AZ, United Kingdom.

The rapid relaxation of above-band-gap "hot" carriers (HCs) imposes the key efficiency limit in lead-halide perovskite (LHP) solar cells. Recent studies have indicated that HC cooling in these systems may be sensitive to materials composition, as well as the energy and density of excited states. However, the key parameters underpinning the cooling mechanism are currently under debate. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.8b01227
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http://dx.doi.org/10.1021/acsenergylett.8b01227DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6231231PMC
September 2018
25 Reads

The Potential of Singlet Fission Photon Multipliers as an Alternative to Silicon-Based Tandem Solar Cells.

ACS Energy Lett 2018 Oct 26;3(10):2587-2592. Epub 2018 Sep 26.

Center for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.

Singlet fission, an exciton multiplication process in organic semiconductors that converts one singlet exciton into two triplet excitons, is a promising way to reduce thermalization losses in conventional solar cells. One way to harvest triplet excitons is to transfer their energy into quantum dots, which then emit photons into an underlying solar cell. We simulate the performance potential of such a singlet fission photon multiplier combined with a silicon base cell and compare it to a silicon-based tandem solar cell. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.8b01322
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http://dx.doi.org/10.1021/acsenergylett.8b01322DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6189909PMC
October 2018
3 Reads

Thermally Activated Second-Order Recombination Hints toward Indirect Recombination in Fully Inorganic CsPbI Perovskites.

ACS Energy Lett 2018 Sep 18;3(9):2068-2069. Epub 2018 Jul 18.

Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.

The relationship between the dipole moment of the methylammonium cation and the optoelectronic properties of lead halide perovskites remains under debate. We show that both the temperature-dependent charge carrier mobility and recombination kinetics are identical for methylammonium and cesium lead iodide, indicating that the role of the monovalent cation is subordinate to the lead iodide framework. From the observation that for both perovskites the electron-hole recombination is thermally activated, we speculate that the bandgap is slightly indirect. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b01106DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6142047PMC
September 2018

Evaluating the Stability of CoP Electrocatalysts in the Hydrogen Evolution Reaction for Both Acidic and Alkaline Electrolytes.

ACS Energy Lett 2018 Jun 16;3(6):1360-1365. Epub 2018 May 16.

Laboratory of Inorganic Materials Chemistry, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven, The Netherlands.

The evaluation of the stability of emerging earth-abundant metal phosphide electrocatalysts by solely electrochemical current-potential sweeps is often not conclusive. In this study, we investigated CoP to evaluate its stability under both acidic (0.5 M HSO) and alkaline (1. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b00514DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5996345PMC

In Situ Fabrication and Reactivation of Highly Selective and Stable Ag Catalysts for Electrochemical CO Conversion.

ACS Energy Lett 2018 Jun 8;3(6):1301-1306. Epub 2018 May 8.

Materials for Energy Conversion and Storage (MECS), Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.

In this work, the highly selective and stable electrocatalytic reduction of CO to CO on nanostructured Ag electrocatalysts is presented. The Ag electrocatalysts are synthesized by the electroreduction of AgCO formed by in situ anodic-etching of Ag foil in a KHCO electrolyte. After 3 min of this etching treatment, the AgCO-derived nanostructured Ag electrocatalysts are capable of producing CO with up to 92% Faradaic efficiency at an overpotential as low as 290 mV, which surpasses all of the reported Ag catalysts at identical conditions to date. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b00472DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5996346PMC
June 2018
13 Reads

Efficient and Stable Silicon Microwire Photocathodes with a Nickel Silicide Interlayer for Operation in Strongly Alkaline Solutions.

ACS Energy Lett 2018 May 9;3(5):1086-1092. Epub 2018 Apr 9.

Molecular NanoFabrication, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.

Most photoanodes commonly applied in solar fuel research (e.g., of FeO, BiVO, TiO, or WO) are only active and stable in alkaline electrolytes. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b00267DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5952259PMC
May 2018
7 Reads

Balancing Charge Carrier Transport in a Quantum Dot P-N Junction toward Hysteresis-Free High-Performance Solar Cells.

ACS Energy Lett 2018 Apr 3;3(4):1036-1043. Epub 2018 Apr 3.

Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom.

In a quantum dot solar cell (QDSC) that has an inverted structure, the QD layers form two different junctions between the electron transport layer (ETL) and the other semiconducting QD layer. Recent work on an inverted-structure QDSC has revealed that the junction between the QD layers is the dominant junction, rather than the junction between the ETL and the QD layers, which is in contrast to the conventional wisdom. However, to date, there have been a lack of systematic studies on the role and importance of the QD heterojunction structure on the behavior of the solar cell and the resulting device performance. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b00130DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5951602PMC
April 2018
13 Reads

Electrochemical Reduction of Carbon Dioxide on Nitrogen-Doped Carbons: Insights from Isotopic Labeling Studies.

ACS Energy Lett 2018 Mar 19;3(3):722-723. Epub 2018 Feb 19.

Department of Physical Chemistry and Materials Science, University of Szeged, Rerrich Square 1, Szeged H-6720, Hungary.

Isotopic labeling experiments were performed to better understand the electrochemical reduction of carbon dioxide on nitrogen-doped porous carbon electrodes. By using nonequilibrated solutions of selectively labeled initial carbon sources (i.e. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b00212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5848144PMC

Colloidal CsPbX (X = Cl, Br, I) Nanocrystals 2.0: Zwitterionic Capping Ligands for Improved Durability and Stability.

ACS Energy Lett 2018 Mar 9;3(3):641-646. Epub 2018 Feb 9.

Institute of Inorganic Chemistry, Department of Chemistry and Applied Bioscience, ETH Zürich, Vladimir Prelog Weg 1, CH-8093 Zürich, Switzerland.

Colloidal lead halide perovskite nanocrystals (NCs) have recently emerged as versatile photonic sources. Their processing and optoelectronic applications are hampered by the loss of colloidal stability and structural integrity due to the facile desorption of surface capping molecules during isolation and purification. To address this issue, herein, we propose a new ligand capping strategy utilizing common and inexpensive long-chain zwitterionic molecules such as 3-(,-dimethyloctadecylammonio)propanesulfonate, resulting in much improved chemical durability. Read More

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http://dx.doi.org/10.1021/acsenergylett.8b00035DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5848145PMC
March 2018
25 Reads

H Evolution with Covalent Organic Framework Photocatalysts.

ACS Energy Lett 2018 Feb 5;3(2):400-409. Epub 2018 Jan 5.

Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.

Covalent organic frameworks (COFs) are a new class of crystalline organic polymers that have garnered significant recent attention as highly promising H evolution photocatalysts. This Perspective discusses the advances in this field of energy research while highlighting the underlying peremptory factors for the rational design of readily tunable COF photoabsorber-cocatalyst systems for optimal photocatalytic performance. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b01123DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5809981PMC
February 2018

Enhanced n-Doping Efficiency of a Naphthalenediimide-Based Copolymer through Polar Side Chains for Organic Thermoelectrics.

ACS Energy Lett 2018 Feb 5;3(2):278-285. Epub 2018 Jan 5.

Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 412 96 Göteborg, Sweden.

N-doping of conjugated polymers either requires a high dopant fraction or yields a low electrical conductivity because of their poor compatibility with molecular dopants. We explore n-doping of the polar naphthalenediimide-bithiophene copolymer p(gNDI-gT2) that carries oligoethylene glycol-based side chains and show that the polymer displays superior miscibility with the benzimidazole-dimethylbenzenamine-based n-dopant N-DMBI. The good compatibility of p(gNDI-gT2) and N-DMBI results in a relatively high doping efficiency of 13% for n-dopants, which leads to a high electrical conductivity of more than 10 S cm for a dopant concentration of only 10 mol % when measured in an inert atmosphere. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.7b01146
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http://dx.doi.org/10.1021/acsenergylett.7b01146DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5809982PMC
February 2018
6 Reads

Postsynthesis Transformation of Insulating CsPbBr Nanocrystals into Bright Perovskite CsPbBr through Physical and Chemical Extraction of CsBr.

ACS Energy Lett 2017 Oct 19;2(10):2445-2448. Epub 2017 Sep 19.

Nanochemistry Department, and Materials Characterization Facility, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.

Perovskite-related CsPbBr nanocrystals present a "zero-dimensional" crystalline structure where adjacent [PbBr] octahedra do not share any corners. We show in this work that these nanocrystals can be converted into "three-dimensional" CsPbBr perovskites by extraction of CsBr. This conversion drastically changes the optoelectronic properties of the nanocrystals that become highly photoluminescent. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00842DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5736241PMC
October 2017
7 Reads

Slow Cooling of Hot Polarons in Halide Perovskite Solar Cells.

ACS Energy Lett 2017 Dec 23;2(12):2647-2652. Epub 2017 Oct 23.

Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, United Kingdom.

Halide perovskites show unusual thermalization kinetics for above-bandgap photoexcitation. We explain this as a consequence of excess energy being deposited into discrete large polaron states. The crossover between low-fluence and high-fluence "phonon bottleneck" cooling is due to a Mott transition where the polarons overlap ( ≥ 10 cm) and the phonon subpopulations are shared. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00862DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5727468PMC
December 2017
8 Reads

Fluorescent Alloy CsPb Mn I Perovskite Nanocrystals with High Structural and Optical Stability.

ACS Energy Lett 2017 Sep 28;2(9):2183-2186. Epub 2017 Aug 28.

Nanochemistry Department, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.

CsPbI nanocrystals are still limited in their use because of their phase instability as they degrade into the yellow nonemitting δ-CsPbI phase within a few days. We show that alloyed CsPb Mn I nanocrystals have essentially the same optical features and crystal structure as the parent α-CsPbI system, but they are stable in films and in solution for periods over a month. The stabilization stems from a small decrease in the lattice parameters slightly increasing the Goldsmith tolerance factor, combined with an increase in the cohesive energy. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00707DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5679661PMC
September 2017
7 Reads

Semi-Interpenetrating Polymer Networks for Enhanced Supercapacitor Electrodes.

ACS Energy Lett 2017 Sep 14;2(9):2014-2020. Epub 2017 Aug 14.

Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom.

Conducting polymers show great promise as supercapacitor materials due to their high theoretical specific capacitance, low cost, toughness, and flexibility. Poor ion mobility, however, can render active material more than a few tens of nanometers from the surface inaccessible for charge storage, limiting performance. Here, we use semi-interpenetrating networks (sIPNs) of a pseudocapacitive polymer in an ionically conductive polymer matrix to decrease ion diffusion length scales and make virtually all of the active material accessible for charge storage. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00466DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5662927PMC
September 2017
9 Reads

Crystallographic Data Support the Carousel Mechanism of Water Supply to the Oxygen-Evolving Complex of Photosystem II.

ACS Energy Lett 2017 Oct 7;2(10):2299-2306. Epub 2017 Sep 7.

Department of Chemistry, Yale University, New Haven, Connecticut 06520-8107, United States.

Photosystem II (PSII) oxidizes water to produce oxygen through a four-step photocatalytic cycle. Understanding PSII structure-function relations is important for the development of biomimetic photocatalytic systems. The quantum mechanics/molecular mechanics (QM/MM) analysis of substrate water binding to the oxygen-evolving complex (OEC) has suggested a rearrangement of water ligands in a carousel mechanism around a key Mn center. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00750DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5644713PMC
October 2017
1 Read

Modeling the Performance Limitations and Prospects of Perovskite/Si Tandem Solar Cells under Realistic Operating Conditions.

ACS Energy Lett 2017 Sep 22;2(9):2089-2095. Epub 2017 Aug 22.

Center for Nanophotonics, AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.

Perovskite/Si tandem solar cells have the potential to considerably out-perform conventional solar cells. Under standard test conditions, perovskite/Si tandem solar cells already outperform the Si single junction. Under realistic conditions, however, as we show, tandem solar cells made from current record cells are hardly more efficient than the Si cell alone. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00596DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5594440PMC
September 2017
11 Reads

Lead Halide Perovskite Nanocrystals in the Research Spotlight: Stability and Defect Tolerance.

ACS Energy Lett 2017 Sep 10;2(9):2071-2083. Epub 2017 Aug 10.

Department of Materials Science and Engineering and Centre for Functional Photonics (CFP), City University of Hong Kong, Kowloon, Hong Kong SAR.

This Perspective outlines basic structural and optical properties of lead halide perovskite colloidal nanocrystals, highlighting differences and similarities between them and conventional II-VI and III-V semiconductor quantum dots. A detailed insight into two important issues inherent to lead halide perovskite nanocrystals then follows, namely, the advantages of defect tolerance and the necessity to improve their stability in environmental conditions. The defect tolerance of lead halide perovskites offers an impetus to search for similar attributes in other related heavy metal-free compounds. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00547DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5594444PMC
September 2017
17 Reads

Vapour-Deposited Cesium Lead Iodide Perovskites: Microsecond Charge Carrier Lifetimes and Enhanced Photovoltaic Performance.

ACS Energy Lett 2017 Aug 28;2(8):1901-1908. Epub 2017 Jul 28.

Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.

Metal halide perovskites such as methylammonium lead iodide (MAPbI) are highly promising materials for photovoltaics. However, the relationship between the organic nature of the cation and the optoelectronic quality remains debated. In this work, we investigate the optoelectronic properties of fully inorganic vapour-deposited and spin-coated black-phase CsPbI thin films. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.7b00591
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http://dx.doi.org/10.1021/acsenergylett.7b00591DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5569666PMC
August 2017
3 Reads

Recombination in Perovskite Solar Cells: Significance of Grain Boundaries, Interface Traps, and Defect Ions.

ACS Energy Lett 2017 May 2;2(5):1214-1222. Epub 2017 May 2.

Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747AG Groningen, The Netherlands.

Trap-assisted recombination, despite being lower as compared with traditional inorganic solar cells, is still the dominant recombination mechanism in perovskite solar cells (PSCs) and limits their efficiency. We investigate the attributes of the primary trap-assisted recombination channels (grain boundaries and interfaces) and their correlation to defect ions in PSCs. We achieve this by using a validated device model to fit the simulations to the experimental data of efficient vacuum-deposited p-i-n and n-i-p CHNHPbI solar cells, including the light intensity dependence of the open-circuit voltage and fill factor. Read More

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http://dx.doi.org/10.1021/acsenergylett.7b00236DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5438194PMC
May 2017
39 Reads

A Silicon-Singlet Fission Tandem Solar Cell Exceeding 100% External Quantum Efficiency with High Spectral Stability.

ACS Energy Lett 2017 Feb 25;2(2):476-480. Epub 2017 Jan 25.

Center for Nanophotonics, AMOLF , Science Park 104, 1098 XG Amsterdam, The Netherlands.

After 60 years of research, silicon solar cell efficiency saturated close to the theoretical limit, and radically new approaches are needed to further improve the efficiency. The use of tandem systems raises this theoretical power conversion efficiency limit from 34% to 45%. We present the advantageous spectral stability of using voltage-matched tandem solar cells with respect to their traditional series-connected counterparts and experimentally demonstrate how singlet fission can be used to produce simple voltage-matched tandems. Read More

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http://dx.doi.org/10.1021/acsenergylett.6b00678DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5330651PMC
February 2017
7 Reads

Insights into Photosystem II from Isomorphous Difference Fourier Maps of Femtosecond X-ray Diffraction Data and Quantum Mechanics/Molecular Mechanics Structural Models.

ACS Energy Lett 2017 Feb 12;2(2):397-407. Epub 2017 Jan 12.

Department of Chemistry, Yale University , New Haven, Connecticut 06520-8107, United States.

Understanding structure-function relations in photosystem II (PSII) is important for the development of biomimetic photocatalytic systems. X-ray crystallography, computational modeling, and spectroscopy have played central roles in elucidating the structure and function of PSII. Recent breakthroughs in femtosecond X-ray crystallography offer the possibility of collecting diffraction data from the X-ray free electron laser (XFEL) before radiation damage of the sample, thereby overcoming the main challenge of conventional X-ray diffraction methods. Read More

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http://dx.doi.org/10.1021/acsenergylett.6b00626DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5307371PMC
February 2017
1 Read

-Methylformamide as a Source of Methylammonium Ions in the Synthesis of Lead Halide Perovskite Nanocrystals and Bulk Crystals.

ACS Energy Lett 2016 Nov 21;1(5):1042-1048. Epub 2016 Oct 21.

Nanochemistry Department, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genova, Italy.

We report chemical routes for the synthesis of both nanocrystals and bulk crystals of methylammonium (MA) lead halide perovskites employing -methylformamide (NMF) as a source of MA ions. Colloidal nanocrystals were prepared by a transamidation reaction between NMF and an alkyl amine (oleylamine). The nanocrystals showed photoluminescence quantum yields reaching 74% for MAPbBr and 60% for MAPbI. Read More

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http://dx.doi.org/10.1021/acsenergylett.6b00521DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5210176PMC
November 2016
19 Reads

Can Pb-Free Halide Double Perovskites Support High-Efficiency Solar Cells?

ACS Energy Lett 2016 Nov 12;1(5):949-955. Epub 2016 Oct 12.

Kathleen Lonsdale Materials Chemistry, Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom; Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom.

The methylammonium lead halides have become champion photoactive semiconductors for solar cell applications; however, issues still remain with respect to chemical instability and potential toxicity. Recently, the CsAgBiX (X = Cl, Br) double perovskite family has been synthesized and investigated as stable nontoxic replacements. We probe the chemical bonding, physical properties, and cation anti-site disorder of CsAgBiX and related compounds from first-principles. Read More

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http://pubs.acs.org/doi/10.1021/acsenergylett.6b00471
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http://dx.doi.org/10.1021/acsenergylett.6b00471DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5210270PMC
November 2016
12 Reads

Plasmonic Nanoparticles as Light-Harvesting Enhancers in Perovskite Solar Cells: A User's Guide.

ACS Energy Lett 2016 Jul 17;1(1):323-331. Epub 2016 Jun 17.

Institute of Materials Science of Seville, Spanish National Research Council- University of Seville , Calle Américo Vespucio 49, 41092 Seville, Spain.

In this Perspective we discuss the implications of employing metal particles of different shape, size, and composition as absorption enhancers in methylammonium lead iodide perovskite solar cells, with the aim of establishing some guidelines for the future development of plasmonic resonance-based photovoltaic devices. Hybrid perovskites present an extraordinarily high absorption coefficient which, as we show here, makes it difficult to extrapolate concepts and designs that are applied to other solution-processed photovoltaic materials. In addition, the variability of the optical constants attained from perovskite films of seemingly similar composition further complicates the analysis. Read More

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http://dx.doi.org/10.1021/acsenergylett.6b00138DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5210271PMC
July 2016
5 Reads

Highly Monodispersed PbS Quantum Dots for Outstanding Cascaded-Junction Solar Cells.

ACS Energy Lett 2016 Oct 28;1(4):834-839. Epub 2016 Sep 28.

Department of Engineering, University of Cambridge , 9 JJ Thomson Avenue, Cambridge CB3 0FA, U.K.

High-performance cascaded-junction quantum dot solar cells (CJQDSCs) are fabricated from as-prepared highly monodispersed lead sulfide QDs. The cells have a high power conversion of 9.05% and a short-circuit current density of 32. Read More

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Source
http://dx.doi.org/10.1021/acsenergylett.6b00294DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5180466PMC
October 2016
12 Reads
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