RSC Advances Blog

Flexible HVO paper as cathode for Li-ion batteries

17 Oct 2011

Could rechargeable batteries for portable electronic devices be flexible and rollable?

Scientists in Singapore show that hydrated vanadium pentoxide (HVO)-based bulky paper are excellent candidates for cathodes in lithium ion batteries. Paper is lightweight, low-cost and flexible and provide many advantages over carbon nanotubes and graphene nanosheets.

The team led by Tuti Mariana Lim and Qingyu Yan, Nanyang Technological University, Singapore prepared bulky paper from HVO nanobelts, which they synthesised using a very efficient hydrothermal method (up to 99% yield). The nanobelts were several micrometers long, ~20nm in diameter and ~10nm in thickness. Flexible bulky-paper cathodes were made without the addition of binders.

“These flexible electrodes show high reversible Li storage capacities, good high C-rate performance with ~100% coulombic efficiency,” claim Lim and Yu.

“These promising properties of binder-free flexible electrodes can be an important step for development of rollable rechargeable battery with desired energy storage performance.”

Read the full paper for free upon a simple registration process:

Facile preparation of hydrated vanadium pentoxide nanobelts based bulky paper as flexible binder-free cathodes for high-performance lithium ion batteries

Xianhong Rui, Jixin Zhu, Weiling Liu, Huiteng Tan, Daohao Sim, Chen Xu, Hua Zhang, Jan Ma, Huey Hoon Hng, Tuti Mariana Lim and Qingyu Yan
RSC Adv., 2011, 1, 117-122

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PVA excellent for solar cell encapsulation

12 Oct 2011

By Kathleen Too, Deputy Editor.

French scientists explain how polyvinyl alcohol (PVA) is an excellent oxygen-barrier polymer for solar cell encapsulation. The team led by Jean-Luc Gardette, at the University of Clermont, conducted photochemical studies of PVA under solar light. They showed that the photooxidative degradation of PVA are restricted to the first 5 micron at the surface of the exposed films. The researchers also identified the low molecular weight products such as carboxylic acids that can be trapped in the film or migrate in the gas phase and they proposed an oxidative mechanism to account for these modifications.

However, the most appealing property of PVA is its “high stability upon irradiation in the absence of oxygen, even after long exposure in conditions of accelerated ageing”, says Gardette. Indeed, PVA is an excellent candidate for the multilayer encapsulation system of Organic Solar Cells (OSCs) due to its high durability, “as long as the PVA layer is protected from
air by an inorganic layer as a first outside layer in the inorganic/organic multistack”.

Photochemical behavior of PVA as an oxygen-barrier polymer for solar cell encapsulation
Julien Gaume, Pascal Wong-Wah-Chung, Agnès Rivaton, Sandrine Thérias and Jean-Luc Gardette
RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00350J

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Detecting vancomycin-resistant bug with DNA sensor

07 Oct 2011

By Kathleen Too, Deputy Editor.

Scientists in China have improved the accuracy of DNA sensors for use in disease detection.

DNA sensors detect pathogenic and genetic diseases by binding to target DNA strands that are related to the disease and giving a signal that shows how much of the DNA is present. Recent developments in the technology make use of gold nanoparticles functionalised with primer strands that bind to the DNA of interest. When the primers link to the targets, changes in the nanoparticles’ UV-visible absorbance provide a quantifiable signal.

Ken Cham-Fai Leung from the Chinese University of Hong Kong and coworkers have modified this approach to improve the sensitivity and accuracy.

Sensors employing gold nanoparticles randomly functionalised with single-stranded primer DNA can lead to primer strand cross-binding, resulting in agglomeration. This can entrap the nanoparticles and reduce the number of primer strands available for binding to the target DNA, leading to inaccurate changes in absorbance signals.

Primer strands attached to a gold nanoparticle

The monofunctionalised nanoparticles form discrete nanostructures (left), whilst randomly functionalised nanoparticles tend to aggregate (right)

To combat this problem, Leung and his team made monofunctionalised gold nanoparticles to which just one primer strand complementary to the target DNA was attached. The team used the nanoparticles to detect a DNA strand just 10 bases long, related to Enterococcus faecalis, a bacterium that can cause life-threatening infections. The shorter primer strands then needed to attach to the nanoparticles displayed reduced steric and electrostatic repulsions, decreasing the tendency for agglomeration. ‘Using these structurally well-defined, monofunctionalised gold nanoparticles will provide more quantitative results for DNA detection,’ says Leung.

The nanoparticle complexes are soluble in organic solvent mixtures in which longer DNA sequences are typically denatured; using such solvents could provide novel approaches for gene delivery.

‘The work has enriched our current understanding of DNA hybridisation in organic media, and it clearly shows good potential for future applications in biomedical research and new sensor developments,’ says Cong Yu, an expert in nucleic acid chemistry from the Changchun Institute of Applied Chemistry, China.

Sarah Farley

The above story was published in Chemistry World on the 7th October 2011: Detecting diseases with DNA sensors

The full article is free to download after a simple registration process:

DNA hybridization of pathogenicity island of vancomycin-resistant Enterococcus faecalis with discretely functionalized gold nanoparticles in organic solvent mixtures
Chun-Pong Chak, Josie M. Y. Lai, Kathy W. Y. Sham, Christopher H. K. Cheng and Ken Cham-Fai Leung, RSC Adv., 2011
DOI:10.1039/c1ra00304f, Advanced Article

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Quasicrystal clear for Nobel Academy

05 Oct 2011

By Kathleen Too, Deputy Editor.

Congratulations to Professor Daniel Shechtman, Technion Israel Institute of Technology, Haifa, Israel, on winning the 2011 Nobel Prize in Chemistry for the discovery of quasicrystals!

“Contrary to the previous belief that atoms were packed inside crystals in symmetrical patterns, Mr. Shechtman showed that the atoms in a crystal could be packed in a pattern that could not be repeated,” said the Nobel Academy.

The latest articles on materials and crystal engineering published in RSC Advances can be freely downloaded:

Insight into the crystal synthesis, activation and application of ZIF-20, Beatriz Seoane, Juan M. Zamaro, Carlos Téllez and Joaquín Coronas, RSC Adv., 2011, 1, 917-922

Tin oxide nanocrystals: controllable synthesis, characterization, optical properties and mechanistic insights into the formation process, Anshu Singhal, Bhaskar Sanyal and Avesh K. Tyagi, RSC Adv., 2011, 1, 903-910

Structures, stabilities and electronic properties of graphdiyne nanoribbons, Hongcun Bai, Ying Zhu, Weiye Qiao and Yuanhe Huang, RSC Adv., 2011, 1, 768-775

Chemical reactions under autogenic pressure at elevated temperature to fabricate photo-luminescent Ga2O3 nanocrystals and their coatings, Pani P. George, Vilas G. Pol, Yuri Koltypin, Makluf Shirly Ben-David, I. Genish and Aharon Gedanken, RSC Adv., 2011, 1, 619-624

Network forming units in alkali borate and borophosphate glasses and the mixed glass former effect, Michael Schuch, Christian Trott and Philipp Maass, RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00583A, Paper

Cu2O microcrystals: a versatile class of self-templates for the synthesis of porous Au nanocages with various morphologies, Xiaowang Liu, RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00250C, Paper

Reduction of Cu2O nanocrystals: reactant-dependent influence of capping ligands and coupling between adjacent crystal planes, Qing Hua, Kai Chen, Sujie Chang, Huizhi Bao, Yunsheng Ma, Zhiquan Jiang and Weixin Huang, RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00431J, Communication

Please note: The above articles can be read for free upon a simple registration process.

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Latest advances in supercapacitors

30 Sep 2011

By Kathleen Too, Deputy Editor.

RSC Advances has published a number of articles displaying the recent advances in supercacitors.

Research conducted by Wei et al., University of Delaware, USA, provide a better understanding of the self-discharge mechanism for CNT-based supercapacitors. This type of study is of practical importance in order to produce supercapacitors with tunable energy retention.

A divided potential driving self-discharge process for single-walled carbon nanotube based supercapacitors, Qing Zhang, Jiepeng Rong and Bingqing Wei, RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00318F, Paper

Novel and interesting materials for supercapacitors are presented by:

Ultraflexible plasmonic nanocomposite aerogel, Yi Chen, Khee Chaw Ng, Wenyi Yan, Yue Tang and Wenlong Cheng
RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00532D, Paper

Controllable synthesis of ZnO-based core/shell nanorods and core/shell nanotubes, Zi-Long Wang, Rui Guo, Gao-Ren Li, Liang-Xin Ding, Yan-Nan Ou and Ye-Xiang Tong, RSC Adv., 2011, 1, 48-51, Communication

An electrochemically formed three-dimensional structure of polypyrrole/graphene nanoplatelets for high-performance supercapacitors, Peng Si, Shujiang Ding, Xiong-Wen (David) Lou and Dong-Hwan Kim, RSC Adv., 2011, Advance Article, DOI: 10.1039/C1RA00519G, Paper

Sequential crystallization of sea urchin-like bimetallic (Ni, Co) carbonate hydroxide and its morphology conserved conversion to porous NiCo2O4 spinel for pseudocapacitors, Junwu Xiao and Shihe Yang, RSC Adv., 2011, 1, 588-595, Paper

One-step synthesis of low defect density carbon nanotube-doped Ni(OH)2 nanosheets with improved electrochemical performances, Sheng Chen, Junwu Zhu, Hui Zhou and Xin Wang, RSC Adv., 2011, 1, 484-489, Paper

Hierarchical nickel sulfide hollow spheres for high performance supercapacitors, By Ting Zhu, Zhiyu Wang, Shujiang Ding, Jun Song Chen and Xiong Wen (David) Lou, RSC Adv., 2011, 1, 397-400, Communication

Peapod-like nickel@mesoporous carbon core-shell nanowires: a novel electrode material for supercapacitors, Hao Jiang, Ting Sun, Chunzhong Li and Jan Ma, RSC Adv., 2011, Advance Article, DOI:10.1039/C1RA00458A, Communication

All of the above articles are free to download after a simple registration process.

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RSC Advances sponsors young chemists at the Asian Chemical Congress

21 Sep 2011

By Kathleen Too, Deputy Editor.

The Royal Society of Chemistry was proud to sponsor the workshop on frontiers in drug discovery research as well as two Young Chemists Awards at the 14th Asian Chemical Congress which was held in Thailand on the 5-8th September 2011. It was one of the largest chemical symposium in Asia with approximately 2000 delegates from over 30 countries (Japan, Taiwan, China, Korea, Malaysia, India, Brunei etc…).

Delegates gathered at the Queen Sikirit Convention Centre, in Bangkok, for four days of chemistry extravaganza. They were exposed to 13 parallel sessions covering a number of subject areas from materials and polymer chemistry to analytical and environmental chemistry, including physical, organic, inorganic and drug discovery sessions. The plenary talks included two Nobel Prize Winners: Ada E Yonath (Nobel Prize in Chemistry, 2009) and Yuan Tseh Lee (Nobel Prize in Chemistry, 1986).

RSC Advances was pleased to present two Young Chemists Awards to MISS SUJITTRA POORAHONG and MISS SALUMA SAMANMAN who presented work on the following:

Cauliflower polyaniline sensor arrays and its applications to detect hydrogen peroxide, S. Poorahong et al.

Highly sensitive label-free capacitive immunosensor based on layer-by-layer self-assembled gold nanoparticles, S. Samanman et al.

Sujittra Poorahong and Kathleen Too

Saluma Samanman and Kathleen Too

Both winners were from the Prince of Songkla University, Trace Analysis and Biosensor Research Center, Faculty of Science, Thailand. The analytical young chemists sessions were chaired by Professors Orawan Chailapakul (Chulalongkorn University), Chongdee Thammakhet (Prince of Songkla University), Gunter Grampp (Graz University of Technology , Austria) and Chutintorn Punwong (Prince of Songkla University). Many congratulations to the winners!

From left to right: Kathleen Too, Chongdee Thammakhet, Sujittra Poorahong, Saluma Samanman, Gunter Grampp, Chutintorn Punwong

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Understanding explosives for safe manufacture

19 Sep 2011

By Kathleen Too, Deputy Editor.

RDX (hexahydro-1,3,5-trinitro-s-triazine) is a rocket propellant but its manufacture comes with high risk of explosion.

Ke-Li Han from the Dalian Institute of Chemical Physics, China, and colleagues have used a computational study to gauge which parts of the synthesis of the RDX precursor TRAT (hexahydro-1,3,5-triacetyl-s-triazine) are most likely to cause an explosion.

They found that of the four stages in the synthesis – imine formation, amino methylation, dehydration and trimerisation – the second and fourth stages are the most likely to release energy in the form of an explosion. The team suggests that more attention is paid to these stages of production.

The full article is free to access upon a simple registration process.

A reaction of formaldehyde with acetonitrile: understanding the preparation of RDX (I), X-F Chen, B-Z Wang and K-L Han, RSC Adv., 2011, DOI: 10.1039/c1ra00239b

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RSC Advances Blog

Top ten most accessed articles in September

Flexible HVO paper as cathode for Li-ion batteries

PVA excellent for solar cell encapsulation

Detecting vancomycin-resistant bug with DNA sensor

Quasicrystal clear for Nobel Academy

Latest advances in supercapacitors

Top ten most accessed articles in August

RSC Advances sponsors young chemists at the Asian Chemical Congress

Understanding explosives for safe manufacture

Top ten most accessed articles in July

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