EES Blog

Seth Darling and co-workers from the USA describe methods to achieve better consistency in high performance of organic solar cells in their recent EES paper.

Batch-to-batch variation in performance of organic solar cells is a well-known problem, for which the underlying causes have been unclear so far. Trace impurities from residual catalyst material, used to synthesise the polymers in these devices, are known to affect device performance. Before now, no technique has been developed for identifying and quantifying impurities, even though they can cause issues with irreproducible optoelectronic function.

The group from Argonne National Laboratory, The University of Chicago and Northwestern University have shown that synchrotron-based X-ray fluorescence can detect and quantify trace concentrations of metal impurities in organic solar cell systems. They have also identified the threshold concentration at which performance degrades and the mechanism for the degradation.

Read the details in their paper today:

Detection and role of trace impurities in high-performance organic solar cells
Maxim P. Nikiforov, Barry Lai, Wei Chen, Si Chen, Richard D. Schaller, Joseph Strzalka, Jörg Maser and Seth B. Darling
DOI: 10.1039/C3EE40556G

Yang Shao-Horn, from MIT, and her co-workers report a novel and interesting study of oxygen reduction reaction (ORR) electrocatalysis on epitaxial perovskite thin films of different Mn valance states.

They were able to demonstrate conclusively that Mn³⁺, not Mn⁴⁺ or Mn²⁺, is the active species for ORR. They also revealed that the substrate can greatly alter the ORR activities of oxide films of a few nanometers in thickness by interfacial charge transfer.

Their findings are very important for the future design of nanostructured catalysts for electrochemical conversion and storage.

Alkaline fuel cells and metal–air batteries are promising carbon-neutral energy sources. However, these devices suffer from efficiency loss due to the slow ORR kinetics, and the cost of precious metal catalysts required to catalyze the ORR. LaMnO₃-based oxides have previously been  found to be among the most active for the ORR with activities comparable to that of Pt. However, ambiguity has existed until now as to which Mn valence state on the surface is responsible for the high ORR activity.

Read this HOT article today:

Oxygen electrocatalysis on (001)-oriented manganese perovskite films: Mn valency and charge transfer at the nanoscale
Kelsey A. Stoerzinger, Marcel Risch, Jin Suntivich, W. M. Lü, Jigang Zhou, Michael D. Biegalski, Hans M. Christen, Ariando, T. Venkatesan and Yang Shao-Horn
DOI: 10.1039/C3EE40321A

George Zhao and co-authors from Australia and China have written an excellent review of graphene-based electrode materials for electrochemical energy storage.

Read this timely summary of the field today:

Stephen Foster and Sajeev John demonstrate numerically that photonic crystal dye-sensitized solar cells (DSSCs) can provide at least a factor of one-third enhancement in solar light absorption and power conversion efficiency relative to their conventional counterparts in their recent EES paper.

Their design, which consists of a lattice of modulated-diameter TiO₂ nanotubes filled with TiO₂ nanoparticles and interstitial regions filled with electrolyte, has the potential of optimizing both light trapping and electron collection.

Read this HOT article today:

Light-trapping in dye-sensitized solar cells
Stephen Foster and Sajeev John
DOI: 10.1039/C3EE40185E

Scientists from Korea present a major step forward in the field of capacitive deionization (CDI) in their recent EES Communication. They cleverly substituted the fixed carbon electrodes used in typical CDI processes with a suspension of active carbon nanoparticles, achieving excellent desalination efficiency.

CDI is a promising water-treatment method. It has the advantage of being more energy efficient that other processes, such as reverse osmosis. However, CDI is not traditionally used for the desalination of salty water, because it requires a discharging step. After the adsorption of a certain amount of ions on the carbon electrodes in the CDI cell, the cell voltage is reduced and the electrodes are shortcircuited.  The new method presented in this Communication  avoids the need for a discharging step, and therefore allows easy scale-up  by simply increasing the number of flow-electrodes used.

Read this HOT Communication today:

Desalination via a new membrane capacitive deionization process utilizing flow-electrodes
Sung-il Jeon, Hong-ran Park, Jeong-gu Yeo, SeungCheol Yang, Churl Hee Cho, Moon Hee Han and Dong Kook Kim
DOI: 10.1039/C3EE24443A

Shi Su and co-authors from Australia have prepared carbon composite monoliths with superior CO₂ adsorption properties and hierarchical macroporous-microporous structures.

They prepared the monoliths by mixing a commercial phenolic resin with a small amount of carbon nanotubes followed by carbonization and physical activation with CO₂.  Their method is simple and low-cost, and may pave the way for more general use of carbon nanotubes in hierarchically porous structured composites for energy and environmental applications.

Read more in this HOT Communication:

Carbon nanotube modified carbon composite monoliths as superior adsorbents for carbon dioxide capture
Yonggang Jin, Stephen C. Hawkins, Chi P. Huynh and Shi Su
DOI: 10.1039/C3EE24441E

Scientists from Pacific Northwest National Laboratory have designed a low-cost Na–ZnCl₂ battery with a planar β′′-Al₂O₃ solid electrolyte. They found that the ZnCl₂-based chemical reactions were complex with multiple electrochemical reactions including liquid-phase formation occurring at temperatures above 253 °C. Their Na-ZnCl₂ battery performs impressively, and offers several advantages over Na-NiCl₂ batteries.

Read this HOT article today:

A novel low-cost sodium–zinc chloride battery
Xiaochuan Lu, Guosheng Li, Jin Y. Kim, John P. Lemmon, Vincent L. Sprenkle and Zhenguo Yang
DOI: 10.1039/C3EE24244G

We would like to share with you a selection of high impact articles, published in Energy & Environmental Science covering the diverse applications of polymers in the broad fields of energy and environmental science.

On behalf of Editor-in-Chief Nate Lewis (Caltech) and Board members Peng Wang (Changchun Institute of Applied Chemistry) and Markus Antonietti (Max Planck Institute of Colloids and Interfaces) we invite you to submit your best research to Energy & Environmental Science.

With an Impact Factor of 9.61 and ranked #1 in its field, Energy & Environmental Science is the ideal place to publish your research.

Read this high-impact polymer research today:

Reviews and Analysis

Strong acceptors in donor–acceptor polymers for high performance thin film transistors
Jonathan D. Yuen and Fred Wudl
DOI: 10.1039/C2EE23505F

Conjugated porous polymers for energy applications
Filipe Vilela, Kai Zhang and Markus Antonietti
DOI: 10.1039/C2EE22002D

Prospects for polymer-based thermoelectrics: state of the art and theoretical analysis
Theodore O. Poehler and Howard E. Katz
DOI: 10.1039/C2EE22124A

Morphology characterization in organic and hybrid solar cells
Wei Chen, Maxim P. Nikiforov and Seth B. Darling
DOI: 10.1039/C2EE22056C

Poly(3-hexylthiophene): synthetic methodologies and properties in bulk heterojunction solar cells
Assunta Marrocchi, Daniela Lanari, Antonio Facchetti and Luigi Vaccaro
DOI: 10.1039/C2EE22129B

Overcoming efficiency challenges in organic solar cells: rational development of conjugated polymers
Hae Jung Son, Bridget Carsten, In Hwan Jung and Luping Yu
DOI: 10.1039/C2EE21608F

Advances in high permeability polymeric membrane materials for CO2 separations
Naiying Du, Ho Bum Park, Mauro M. Dal-Cin and Michael D. Guiver
DOI: 10.1039/C1EE02668B

Manufacture, integration and demonstration of polymer solar cells in a lamp for the “Lighting Africa” initiative
Frederik C. Krebs, Torben D. Nielsen, Jan Fyenbo, Mads Wadstrøm and Marie S. Pedersen
DOI: 10.1039/B918441D

Magnesium nanocrystal-polymer composites: A new platform for designer hydrogen storage materials
Rizia Bardhan, Anne M. Ruminski, Alyssa Brand and Jeffrey J. Urban
DOI: 10.1039/C1EE02258J

Recent advances in non-precious metal catalysis for oxygen-reduction reaction in polymer electrolyte fuel cells
Frédéric Jaouen, Eric Proietti, Michel Lefèvre, Régis Chenitz, Jean-Pol Dodelet, Gang Wu, Hoon Taek Chung, Christina Marie Johnston and Piotr Zelenay
DOI: 10.1039/C0EE00011F

Hydrocarbon proton conducting polymers for fuel cell catalyst layers
Jennifer Peron, Zhiqing Shi and Steven Holdcroft
DOI: 10.1039/C0EE00638F

Organic photovoltaics
Bernard Kippelen and Jean-Luc Brédas
DOI: 10.1039/B812502N

Tandem polymer photovoltaic cells—current status, challenges and future outlook
Srinivas Sista, Ziruo Hong, Li-Min Chen and Yang Yang
DOI: 10.1039/C0EE00754D

Life-cycle analysis of product integrated polymer solar cells
Nieves Espinosa, Rafael García-Valverde and Frederik C. Krebs
DOI: 10.1039/C1EE01127H

Original Research

Reversible CO2 capture with porous polymers using the humidity swing
Hongkun He, Wenwen Li, Mingjiang Zhong, Dominik Konkolewicz, Dingcai Wu, Karin Yaccato, Tim Rappold, Glenn Sugar, Nathaniel E. David and Krzysztof Matyjaszewski
DOI: 10.1039/C2EE24139K

Disentangling the impact of side chains and fluorine substituents of conjugated donor polymers on the performance of photovoltaic blends
Liqiang Yang, John R. Tumbleston, Huaxing Zhou, Harald Ade and Wei You
DOI: 10.1039/C2EE23235A

Integrated energy storage and electrochromic function in one flexible device: an energy storage smart window
Kai Wang, Haiping Wu, Yuena Meng, Yajie Zhang and Zhixiang Wei
DOI: 10.1039/C2EE21643D

Electrospun and solution blown three-dimensional carbon fiber nonwovens for application as electrodes in microbial fuel cells
Shuiliang Chen, Haoqing Hou, Falk Harnisch, Sunil A. Patil, Alessandro A. Carmona-Martinez, Seema Agarwal, Yiyun Zhang, Suman Sinha-Ray, Alexander L. Yarin, Andreas Greiner and Uwe Schröder
DOI: 10.1039/C0EE00446D

Seamless polymer solar cell module architecture built upon self-aligned alternating interfacial layers
Jongjin Lee, Hyungcheol Back, Jaemin Kong, Hongkyu Kang, Suhee Song, Hongsuk Suh, Sung-Oong Kang and Kwanghee Lee
DOI: 10.1039/C3EE24454G

Microporous organic polymers for carbon dioxide capture
Robert Dawson, Ev Stöckel, James R. Holst, Dave J. Adams and Andrew I. Cooper
DOI: 10.1039/C1EE01971F

High mobility organic thin film transistor and efficient photovoltaic devices using versatile donor–acceptor polymer semiconductor by molecular design
Prashant Sonar, Samarendra P. Singh, Yuning Li, Zi-En Ooi, Tae-jun Ha, Ivy Wong, Mui Siang Soh and Ananth Dodabalapur
DOI: 10.1039/C1EE01213D

Highly durable and flexible dye-sensitized solar cells fabricated on plastic substrates: PVDF-nanofiber-reinforced TiO2 photoelectrodes
Yuelong Li, Doh-Kwon Lee, Jin Young Kim, BongSoo Kim, Nam-Gyu Park, Kyungkon Kim, Joong-Ho Shin, In-Suk Choi and Min Jae Ko
DOI: 10.1039/C2EE21674D

Inverted polymer solar cells with 8.4% efficiency by conjugated polyelectrolyte
Tingbin Yang, Ming Wang, Chunhui Duan, Xiaowen Hu, Lin Huang, Junbiao Peng, Fei Huang and Xiong Gong
DOI: 10.1039/C2EE22296E

First implementation of alkaline polymer electrolyte water electrolysis working only with pure water
Li Xiao, Shuai Zhang, Jing Pan, Cuixia Yang, Minglong He, Lin Zhuang and Juntao Lu
DOI: 10.1039/C2EE22146B

Improving the cycling stability of silicon nanowire anodes with conducting polymer coatings
Yan Yao, Nian Liu, Matthew T. McDowell, Mauro Pasta and Yi Cui
DOI: 10.1039/C2EE21437G