Recent progress in the development and use of organic ionic plastic crystal electrolytes

Significant progress has been made recently in the development of Organic Ionic Plastic Crystals (OIPCs), a unique family of solid state electrolytes with applications in electrochemical devices such as lithium batteries and dye-sensitised solar cells. The negligible volatility of OIPCs renders them more suitable than molecular species for long-term device use, while the high thermal and electrochemical stability of many OIPCs fulfils an essential requirement for solid state electrolytes for many device applications. However, the complex mechanisms of conduction through these materials, both in their pure state and in the presence of a small amount of a second component (such as lithium salts to enable their use in lithium batteries) are still not fully understood. At the same time, the range of anions and cations utilised in the synthesis of plastic crystal phases continues to increase. This perspective concentrates on recent research into both fundamental and device-oriented aspects of these materials. Important fundamental understanding of the physical properties and transport mechanisms of different OIPCs has been achieved through use of techniques including variable temperature solid-state NMR and crystallographic analysis, as well as detailed molecular dynamics simulations. In parallel, the applicability of these materials as electrolytes for dye-sensitised solar cells and lithium batteries is being more widely demonstrated. The possibility of using OIPCs as solid state electrolytes for fuel cells is also discussed.

Beyond the usual suspects: complexity of fragility and analytical framework

Development in so-called ‘fragile states’ has become a key priority for the international community over the past few years, but international actors have not yet adequately incorporated sufficiently nuanced understandings of fragility into policies or practices. The increasing proportion of the world’s poor living in fragile contexts, the depth of human need in these contexts, and the potential regional spillover implications of this fragility, all make this an urgent concern. This chapter examines this growing need and discusses the origins and methodological approach in this volume, before setting up the rest of the book with definitions and an analysis framework. The chapter concludes with a summary of the book chapters and contributions.

Remittances and economic growth: larger impacts in smaller countries?

This paper examines the impact of remittances on economic growth in Small Island Developing States (SIDS). Results from variants of an empirical model suggest that while, on average, there is at best no association between remittances and growth in developing countries, there is a positive association between these variables in SIDS. This finding holds for SIDS in sub-Saharan Africa and the Pacific but not for those in Latin America and the Caribbean. Relationships between remittances, economic volatility, and household labour supply are offered as reasons for these findings.

Quotas, spillovers, and the transfer paradox in an economy with tourism

This paper examines the welfare implications of quotas for an economy that is small in terms of traditionally traded goods and has monopoly power over the trade of goods consumed by tourists. Inbound tourism converts local nontraded goods into tradable goods, creating a tourism terms-of-trade effect for the touristreceiving economy. Through this effect, quotas result in a spillover to the nontraded sector. Hence, in the presence of tourism, the traditional free-trade prescription for the small open economy is no longer valid. This lends support to the setting of import quotas. Using the optimal quota as a benchmark, we further examine the welfare effect of tied aid. If tied aid brings about an excessive supply of importable goods, then the transfer paradox of the immiserization of the tourist- receiving economy may occur.

Characterization of decamethylferrocene and ferrocene in ionic liquids : Argon and vacuum effect on their electrochemical propertiesce

The electrochemistry of decamethylferrocene (DmFc) has been studied in organic solvent systems and proven to be a superior internal reference redox standard to ferrocene (Fc). However, the electrochemical information on this redox couple in ionic liquids is still limited. Therefore, the voltammetric and amperometric behaviour of DmFc was investigated under argon and vacuum conditions in six different ionic liquids and compared to that of Fc under the same experimental conditions. Consequently, the concentration, the heterogeneous electron-transfer rate constant (k0), volatility, and diffusion coefficients (D) of Fc and Fc+, as well as the solubility, k 0, and D values for DmFc and DmFc+ were determined under argon and vacuum conditions by fitting the experimental chronoamperometric and voltammetric data with numerical and digital simulations. The rate of mass transport of ferrocene and decamethylferrocene was observed to decreases between 6-37% by changing the working atmosphere from argon to vacuum. The D Fc/DFc+ ratios are in the range 1.31-2.01 in the different ILs. Importantly, the DDmFc/DDmFc+ ratio is ≈ 1 in 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)amide, 1-methyl-1-butylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate, and 1-methyl-3-ethylimidazolium tris(pentafluoroethyl)trifluorophosphate. The experimental mid-point potential and half-wave potential of Fc0/+ vs. DmFc0/+, as well as the formal potential obtained after correction for inequality in the respective diffusion coefficients of both redox processes are presented. Even though DmFc is not freely soluble in the different ILs, the results presented in this work suggest that the DmFc0/+ redox process is less dependent than Fc on the IL nature. This is a very relevant finding for the application of this transition-metal sandwich complex as an internal reference redox system in IL solutions. © 2014 Elsevier Ltd.

Ionic liquid electrolytes as a platform for rechargeable metal–air batteries: a perspective

Metal-air batteries are a well-established technology that can offer high energy densities, low cost and environmental responsibility. Despite these favourable characteristics and utilisation of oxygen as the cathode reactant, these devices have been limited to primary applications, due to a number of problems that occur when the cell is recharged, including electrolyte loss and poor efficiency. Overcoming these obstacles is essential to creating a rechargeable metal-air battery that can be utilised for efficiently capturing renewable energy. Despite the first metal-air battery being created over 100 years ago, the emergence of reactive metals such as lithium has reinvigorated interest in this field. However the reactivity of some of these metals has generated a number of different philosophies regarding the electrolyte of the metal-air battery. Whilst much is already known about the anode and cathode processes in aqueous and organic electrolytes, the shortcomings of these electrolytes (i.e. volatility, instability, flammability etc.) have led some of the metal-air battery community to study room temperature ionic liquids (RTILs) as non-volatile, highly stable electrolytes that have the potential to support rechargeable metal-air battery processes. In this perspective, we discuss how some of these initial studies have demonstrated the capabilities of RTILs as metal-air battery electrolytes. We will also show that much of the long-held mechanistic knowledge of the oxygen electrode processes might not be applicable in RTIL based electrolytes, allowing for creative new solutions to the traditional irreversibility of the oxygen reduction reaction. Our understanding of key factors such as the effect of catalyst chemistry and surface structure, proton activity and interfacial reactions is still in its infancy in these novel electrolytes. In this perspective we highlight the key areas that need the attention of electrochemists and battery engineers, in order to progress the understanding of the physical and electrochemical processes in RTILs as electrolytes for the various forms of rechargeable metal-air batteries.

Does cash flow predict returns?

In this paper, we propose the hypothesis that cash flow and cash flow volatility predict returns. We categorize firms listed on the New York Stock Exchange into sectors, and apply tests for both in-sample and out-of-sample predictability. While we find strong evidence that cash flow volatility predicts returns for all sectors, the evidence obtained when using cash flow as a predictor is relatively weak. Estimated profits and utility gains also suggest that it is cash flow volatility that is more relevant as a source of information than cash flow.

The role of positive and negative affectivity on job satisfaction and life satisfaction

This study examines the relationship between positive affectivity, negative affectivity, job satisfaction, and life satisfaction using a sample of 558 urban employees from Dalian. Positive and negative affectivity were measured with Watson's PANAS scale, job satisfaction was measured with Spector's JSS scale, and life satisfaction was measured with the International Wellbeing Group's PWI scale. All the scales are well established multi-item scales that have been validated both in English speaking populations and in China. The statistical analysis found that affectivity is a source of both job satisfaction and life satisfaction. Job satisfaction is positively related to life satisfaction, supporting the spillover theory. Job satisfaction partly mediates the relationship between affectivity and life satisfaction. The practical implications for managers is that because of the dispositional source of job and life satisfaction, managers need to put more emphasis on improving job satisfaction and subjective quality of life by improving the workplace environment. ©2009 IEEE.

New empirical evidence on the bid-ask spread

In this article, we model the determinants of spread for 734 firms listed on the NYSE over the period 1 January 1998 to 31 December 2008. We propose a panel data model of the determinants of spread. There are four main messages emerging from our work. We find a statistically significant effect of volume on spread inconsistent with the work of Johnson (2008). On price, we find mixed results, consistent with the literature. On the effect of price volatility on spread, our results are completely the opposite of the cross-sectional literature but sides with the relatively recent work of Chordia et al. (2001). We allow for persistence of spread as a determinant of spread and find significant evidence of spread persistence across all 16 sectors. Finally, we examine size effects and find statistically strong evidence of size effects based on the relationship between price and spread, persistence and spread, and volatility and spread.

Call auction transparency and market liquidity: Evidence from China

This paper uses the natural experiment offered by the Shanghai Stock Exchange to investigate the impact of opening call auction transparency on market liquidity. We find that the dissemination of indicative trade information during the pre-open call auction session leads to an overall improvement in stock liquidity in the continuous trading session. Bid-ask spreads narrow in the first trading hour because adverse selection risk fell significantly and there is less price volatility in the continuous market. This effect is greater for actively traded securities than illiquid securities. Our findings are robust for different lengths of sample period, different lengths of trading hours after market open, and stocks that had (and had not) reformed the share split structure during our research period.

No news is not good news: evidence from the intra-day return volatility–volume relationship in Shanghai Stock Exchange

Through this research, we find that the asymmetric volatility phenomenon is reversed in the Shanghai Stock Exchange during bull markets. That is, volatility increases more with good news than with bad news. This evidence is inconsistent with the US markets. Further examination of this phenomenon reveals that the positive impact of good news on volatility is driven by the return-chasing behaviour of investors during bull markets. We also find that volatility increases after stock price declines in bear markets. After controlling for liquidity shifts, we observe similar patterns in volatility in both bull and bear markets. We posit that institutional and behavioural factors are the major driving forces of observed volatility patterns in the Chinese stock market.

Stock price comovement: Evidence from India

We examine the extent to which stock prices comove in an emerging economy, India. We first document that stocks listed on the National Stock Exchange (NSE) comove. Further, we find that synchronicity is positively associated with growth and earnings volatility and negatively associated with business group affiliation and leverage.