Microscopic and spectroscopic investigation of poly(3-hexylthiophene) interaction with carbon nanotubes

The inclusion of carbon nanotubes in polymer matrix has been proposed to enhance the polymer’s physical and electrical properties. In this study, microscopic and spectroscopic techniques are used to investigate the interaction between poly(3-hexylthiophene) (P3HT) and nanotubes and the reciprocal modification of physical properties. The presence of P3HT-covered nanotubes dispersed in the polymer matrix has been observed by atomic force microscopy and transmission electron microscopy. Then, the modification of P3HT optical properties due to nanotube inclusion has been evidenced with spectroscopic techniques like absorption and Raman spectroscopy. The study is completed with detailed nanoscale analysis by scanning probe techniques. The ordered self assembly of polymer adhering on the nanotube is unveiled by showing an example of helical wrapping of P3HT. Scanning tunneling spectroscopy study provides information on the electronic structure of nanotube-polymer assembly, revealing the charge transfer from P3HT to the nanotube.

Towards a global carbon integrity system : learning from the GFC and avoiding a GCC

This paper examines some of the central global ethical and governance challenges of climate change and carbon emis-sions reduction in relation to globalization, the “global financial crisis” (GFC), and unsustainable conceptions of the “good life”, and argues in favour of the development of a global carbon “integrity system”. It is argued that a funda-mental driver of our climate problems is the incipient spread of an unsustainable Western version of the “good life”, where resource-intensive, high-carbon western lifestyles, although frequently criticized as unsustainable and deeply unsatisfying, appear to have established an unearned ethical legitimacy. While the ultimate solution to climate change is the development of low carbon lifestyles, the paper argues that it is also important that economic incentives support and stimulate that search: the sustainable versions of the good life provide an ethical pull, whilst the incentives provide an economic push. Yet, if we are going to secure sustainable low carbon lifestyles, it is argued, we need more than the ethical pull and the economic push. Each needs to be institutionalized—built into the governance of global, regional, national, sub-regional, corporate and professional institutions. Where currently weakness in each exacerbates the weaknesses in others, it is argued that governance reform is required in all areas supporting sustainable, low carbon versions of the good life.

Microscale study of electrical characteristics of epoxy-multiwall carbon nanotube nanocomposites

Epoxy-multiwall carbon nanotube nanocomposite thin films were prepared by spin casting. High power air plasma was used to preferentially etch a coating of epoxy and expose the underlying carbon nanotube network. Scanning electron microscopy (SEM) examination revealed well distributed and spatially connected carbon nanotube network in both the longitudinal direction (plasma etched surface) and traverse direction (through-thickness fractured surface). Topographical examination and conductive mode imaging of the plasma etched surface using atomic force microscope (AFM) in the contact mode enabled direct imaging of topography and current maps of the embedded carbon nanotube network. Bundles consisting of at least three single carbon nanotubes form part of the percolating network observed under high resolution current maps. Predominantly non-ohmic response is obtained in this study; behaviour attributed to less than effective polymer material removal when using air plasma etching.

Novel corrosion sensor based on carbon nanotube composites for structural health monitoring

Bridges are important infrastructures of all nations and are required for transportation of goods as well as human. A catastrophic failure can result in loss of lives and enormous financial hardship to the nation. Hence, there is an urgent need to monitor our infrastructures to prolong their life span, at the same time catering for heavier and faster moving traffics. Although various kinds of sensors are now available to monitor the health of the structures due to corrosion, they do not provide permanent and long term measurements. This paper investigates the fabrication of Carbon Nanotube (CNT) based composite sensors for structural health monitoring. The CNTs, a key material in nanotechnology has aroused great interest in the research community due to their remarkable mechanical, electrochemical, piezoresistive and other physical properties. Multi-wall CNT (MWCNT)/Nafion composite sensors were fabricated to evaluate their electrical properties when subjected to chemical solutions, to simulate a chemical reaction due to corrosion and real life corrosion experimental tests. The electrical resistance of the sensor electrode was dramatically changed due to corrosion. The novel sensor is expected to effectively detect corrosion in structures based on the measurement of electrical impedances of the CNT composite.

Measuring and monitoring soil organic carbon stocks in agricultural lands for climate mitigation

Policies that encourage greenhouse-gas emitters to mitigate emissions through terrestrial carbon (C) offsets – C sequestration in soils or biomass – will promote practices that reduce erosion and build soil fertility, while fostering adaptation to climate change, agricultural development, and rehabilitation of degraded soils. However none of these benefits will be possible until changes in C stocks can be documented accurately and cost-effectively. This is particularly challenging when dealing with changes in soil organic C (SOC) stocks. Precise methods for measuring C in soil samples are well established, but spatial variability in the factors that determine SOC stocks makes it difficult to document change. Widespread interest in the benefits of SOC sequestration has brought this issue to the fore in the development of US and international climate policy. Here, we review the challenges to documenting changes in SOC stocks, how policy decisions influence offset documentation requirements, and the benefits and drawbacks of different sampling strategies and extrapolation methods.

Using Fiber Bragg Grating (FBG) sensors for vertical displacement measurement of bridges

In many bridges, vertical displacements are one of the most relevant parameters for structural health monitoring in both the short and long terms. Bridge managers around the globe are always looking for a simple way to measure vertical displacements of bridges. However, it is difficult to carry out such measurements. On the other hand, in recent years, with the advancement of fiber-optic technologies, fiber Bragg grating (FBG) sensors are more commonly used in structural health monitoring due to their outstanding advantages including multiplexing capability, immunity of electromagnetic interference as well as high resolution and accuracy. For these reasons, using FBG sensors is proposed to develop a simple, inexpensive and practical method to measure vertical displacements of bridges. A curvature approach for vertical displacement measurement using curvature measurements is proposed. In addition, with the successful development of a FBG tilt sensors, an inclination approach is also proposed using inclination measurements. A series of simulation tests of a full-scale bridge was conducted. It shows that both the approaches can be implemented to determine vertical displacements for bridges with various support conditions, varying stiffness (EI) along the spans and without any prior known loading. These approaches can thus measure vertical displacements for most of slab-on-girder and box-girder bridges. Moreover, with the advantages of FBG sensors, they can be implemented to monitor bridge behavior remotely and in real time. Further recommendations of these approaches for developments will also be discussed at the end of the paper.

Fiber Bragg Grating sensors for railway systems

Fiber Bragg grating (FBG) sensor technology has been attracting substantial industrial interests for the last decade. FBG sensors have seen increasing acceptance and widespread use for structural sensing and health monitoring applications in composites, civil engineering, aerospace, marine, oil & gas, and smart structures. One transportation system that has been benefitted tremendously from this technology is railways, where it is of the utmost importance to understand the structural and operating conditions of rails as well as that of freight and passenger service cars to ensure safe and reliable operation. Fiberoptic sensors, mostly in the form of FBGs, offer various important characteristics, such as EMI/RFI immunity, multiplexing capability, and very long-range interrogation (up to 230 km between FBGs and measurement unit), over the conventional electrical sensors for the distinctive operational conditions in railways. FBG sensors are unique from other types of fiber-optic sensors as the measured information is wavelength-encoded, which provides self-referencing and renders their signals less susceptible to intensity fluctuations. In addition, FBGs are reflective sensors that can be interrogated from either end, providing redundancy to FBG sensing networks. These two unique features are particularly important for the railway industry where safe and reliable operations are the major concerns. Furthermore, FBGs are very versatile and transducers based on FBGs can be designed to measure a wide range of parameters such as acceleration and inclination. Consequently, a single interrogator can deal with a large number of FBG sensors to measure a multitude of parameters at different locations that spans over a large area.

Legal issues in carbon farming : biosequestration, carbon pricing, and carbon rights

This paper critically analyses the proposed Australian regulatory approach to the crediting of biological sequestration activities (biosequestration) under the Australian Carbon Farming Initiative and its interaction with State-based carbon rights, the national carbon-pricing mechanism, and the international Kyoto Protocol and carbon-trading markets. Norms and principles have been established by the Kyoto Protocol to guide the creation of additional, verifiable, and permanent credits from biosequestration activities. This paper examines the proposed arrangements under the Australian Carbon Farming Initiative and Carbon Pricing Mechanism to determine whether they are consistent with those international norms and standards. This paper identifies a number of anomalies associated with the legal treatment of additionality and permanence and issuance of carbon credits within the Australian schemes. In light of this, the paper considers the possible legal implications for the national and international transfer, surrender and use of these offset credits.

Polymer self assembly on carbon nanotubes

This chapter analyses the poly(3-hexylthiophene) self-assembly on carbon nanotubes and the interaction between the two materials forming a new hybrid nanostructure. The chapter starts with a review of the several studies investigating polymers and biomolecules self-assembled on nanotubes. Then conducting polymers and polythiophenes are briefly introduced. Accordingly, carbon nanotube structure and properties are reported in Sect. 3. The experimental section starts with the bulk characterisation of polymer thin films with the inclusion of uniformly distributed carbon nanotubes. By using volume film analysis techniques (AFM, TEM, UV–Vis and Raman), we show how the polymer’s higher degree of order is a direct consequence of interaction with carbon nanotubes. Nevertheless, it is through the use of nanoscale analysis and molecular dynamic simulations that the self-assembly of the polymer on the nanotube surface can be clearly evidenced and characterised. In Sect. 6, the effect of the carbon templating structure on the P3HT organisation on the surface is investigated, showing the chirality-driven polymer assembly on the carbon nanotube surface. The interaction between P3HT and CNTs brings also to charge transfer, with the modification of physical properties for both species. In particular, the alteration of the polymer electronic properties and the modification of the nanotube mechanical structure are a direct consequence of the P3HT p-p stacking on the nanotube surface. Finally, some considerations based on molecular dynamics studies are reported in order to confirm and support the experimental results discussed.

Real estate issues associated with the implementation of a carbon trading framework : a rural landholders perspective

The issue of carbon sequestration rights has become topical following the United Nations Convention on Climate Change and the subsequent Kyoto Protocol which identified emissions trading as one of the mechanisms to reduce greenhouse gas emissions. The Australian Government has responded by initiating the Garnaut Climate Change Review which in its final report, proposed that an emissions trading scheme be introduced and set out some of the desirable features of such a trading scheme. This proposal has been the subject of much debate and at this stage there still seems to be little clarity surrounding the topic of emissions trading in Australia. The treatment of rights to carbon sequestered in vegetation is also an issue when reconciled with the system of land tenure and ownership in many jurisdictions. These carbon property rights are treated differently in different Australian and international jurisdictions ranging from recognition of their new and unique nature to fitting them within a more established common law framework, e.g.a profit a prendre. This paper identifies the treatment of these sequestered carbon rights within the wider property rights framework in Australia and considers issues that this treatment may inflict on land holders when there is a fracturing of ownership between the rights of the carbon in vegetation and the ownership of the land.

The legal framework for Australia's carbon pricing mechanism : a critique

As part of the Australian Government’s Clean Energy Plan, the Government has attempted to harness the legal innovation of the tradeable emissions unit, within a capped carbon trading system, to reduce greenhouse gas emissions. Such an approach promises to send a price signal to the market which will influence emitting behaviours and reduce our emissions in a cost-effective manner. However, if the carbon trading scheme is to successfully achieve cost-effective emissions reductions then the carbon market must be supported by an appropriate legal framework. This paper will consider the key features of the Australian Carbon Pricing Mechanism, including the Carbon Farming Initiative, and critique whether it has all the hallmarks of an effective legal framework to reduce Australia’s net greenhouse gas emissions. The likely future of the trading scheme, following the 2013 elections, will also be addressed.

Book review : "Carbon Capture and Storage Emerging Legal and Regulatory Issues" edited by Ian Havercroft, Richard Macrory, Richard B Stewart, Oxford, Hart Publishing, 2011

As the international community struggles to find a cost-effective solution to mitigate climate change and reduce greenhouse gas emissions, carbon capture and storage (CCS) has emerged as a project mechanism with the potential to assist in transitioning society towards its low carbon future. Being a politically attractive option, legal regimes to promote and approve CCS have proceeded at an accelerated pace in multiple jurisdictions including the European Union and Australia. This acceleration and emphasis on the swift commercial deployment of CCS projects has left the legal community in the undesirable position of having to advise on the strengths and weaknesses of the key features of these regimes once they have been passed and become operational. This is an area where environmental law principles are tested to their very limit. On the one hand, implementation of this new technology should proceed in a precautionary manner to avoid adverse impacts on the atmosphere, local community and broader environment. On the other hand, excessive regulatory restrictions will stifle innovation and act as a barrier to the swift deployment of CCS projects around the world. Finding the balance between precaution and innovation is no easy feat. This is an area where lawyers, academics, regulators and industry representatives can benefit from the sharing of collective experiences, both positive and negative, across the jurisdictions. This exemplary book appears to have been collated with this philosophy in mind and provides an insightful addition to the global dialogue on establishing effective national and international regimes for the implementation of CCS projects...

Temperature dependent electrical resistivity in expoxy : multiwall carbon nanotube nanocomposites

Thin films of expoxy nanocomposites modified by multiwall carbon nanotubes (MWCNTs) were prepared by shear mixing and spin casting. The electrical behaviour and its dependence with temperature between 243 and 353 degrees Kelvin were characterized by measuring the direct current (DC) conductivity. Depending on the fabrication process, both linear and non-linear relationships between conductivity and temperature were observed. In addition, the thermal history also played a role in dictating the conductivity. The implications of these observations for potential application of these files as strain sensors are discussed.

Legal liability for carbon capture and storage in Australia : where should the losses fall?

This article presents a critical analysis of the current and proposed CCS legal frameworks across a number of jurisdictions in Australia in order to examine the legal treatment of the risks of carbon leakage from CCS operations. It does so through an analysis of the statutory obligations and liability rules established under the offshore Commonwealth and Victorian regimes, and onshore Queensland and Victorian legislative frameworks. Exposure draft legislation for CCS laws in Western Australia is also examined. In considering where the losses will fall in the event of leakage, the potential tortious and statutory liabilities of private operators and the State are addressed alongside the operation of statutory protections from liability. The current legal treatment of CCS under the new Australian Carbon Pricing Mechanism is also critiqued.

Controlled growth of carbon nanotubes for electronic and photovoltaic applications

Carbon nanotubes (CNTs), experimentally observed for the first time twenty years ago, have triggered an unprecedented research effort, on the account of their astonishing structural, mechanical and electronic properties. Unfortunately, the current inability in predicting the CNTs’ properties and the difficulty in controlling their position on a substrate are often limiting factors for the application of this material in actual devices. This research aims at the creation of specific methodologies for controlled synthesis of CNTs, leading to effectively employ them in various fields of electronics, e.g. photovoltaics. Focused Ion Beam (FIB) patterning of Si surfaces is here proposed as a means for ordering the assembly of vertical-aligned CNTs. With this technique, substrates with specific nano-structured morphologies have been prepared, enabling a high degree of control over CNTs’ position and size. On these nano-structured substrates, the growth of CNTs has been realized by chemical vapor deposition (CVD), i.e. thermal decomposition of hydrocarbon gases over a heated catalyst. The most common materials used as catalysts in CVD are transition metals like Fe and Ni; however, their presence in the CNT products often results in shortcomings for electronic applications, especially for those based on silicon, being the metallic impurities incompatible with very-large-scale integration (VLSI) technology. In the present work the role of Ge dots as an alternative catalysts for CNTs synthesis on Si substrates has been thoroughly assessed, finding a close connection between the catalytic activity of such material and the CVD conditions, which can affect both size and morphology of the dots. Successful CNT growths from Ge dots have been obtained by CVD at temperatures ranging from 750 to 1000°C, with mixtures of acetylene and hydrogen in an argon carrier gas. The morphology of the Si surface is observed to play a crucial role for the outcome of the CNT synthesis: natural (i.e. chemical etching) and artificial (i.e. FIB patterning, nanoindentation) means of altering this morphology in a controlled way have been then explored to optimize the CNTs yield. All the knowledge acquired in this study has been finally applied to synthesize CNTs on transparent conductive electrodes (indium-tin oxide, ITO, coated glasses), for the creation of a new class of anodes for organic photovoltaics. An accurate procedure has been established which guarantees a controlled inclusion of CNTs on ITO films, preserving their optical and electrical properties. By using this set of conditions, a CNTenhanced electrode has been built, contributing to improve the power conversion efficiency of polymeric solar cells.