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We fabricated the first solid state modules based on organometal halide perovskite CH3NH3PbI3−xClx using Spiro-OMeTAD and poly(3-hexylthiophene) as hole transport materials. Device up-scaling was performed using innovative procedures to realize large-area cells and the integrated series-interconnections. The perovskite-based modules show a maximum conversion efficiency of 5.1% using both poly(3-hexylthiophene) and Spiro-OMeTAD. A long-term stability test was performed (in air, under AM1.5G, 1 Sun illumination conditions) using both materials showing different behaviour under continuous light stress. Whilst the poly(3-hexylthiophene)-based module efficiency drops by about 80% with respect to the initial value after 170 hours, the Spiro-based module shows a promising long-term stability maintaining more than 60% of its initial efficiency after 335 hours.

We have analysed and optimised a laser process for the sintering of the TiO2 layers in dye solar cells (DSCs). Through a thermographic characterisation of the process, we show that it is possible to scale and process large areas uniformly (16 cm2). We fabricated DSCs with nanocrystalline (nc)-TiO2 films sintered by using pulsed ultraviolet laser with an average output power P varying from 1 W to 7 W whilst mainting a constant power conversion efficiency eta. The highest efficiency reached for a laser sintered DSC was 7%. The time required to sinter 1 m2 of nc-TiO2 film was found to decrease hyperbolically with P, which is important for determining process takt times. We quantified the embodied energy (EE) required to sinter 1 m2 of the active TiO2 layer for a variety of different processes, and found that the EE for the laser sintering process with a system wall plug efficiency of 3.5% to be competitive with the more conventional oven and belt furnace treatments. We outline the main features required from a laser system to carry out an efficient, energetically favourable and industrially applicable automated process with competitive throughput.

Here for the first time an high power, high repetition rate, ultra short pulses, Yb doped fiber laser has been used jointly with a trepanning head to carry out hole trepanning trials in 900 µm thick stainless steel L316. Holes with aspect ratio up to 24 have been shown. Holes geometry has been characterized showing a profile which is cylindrical. The trepanning time has been optimized and reduced to 1.5 s. These results show not only the huge potential introduced in material hole trepanning by coupling high power, high repetition rate, fs laser with an innovative trepanning head but also pave the way for the application of laser trepanning in future fields such as automotive and microelectronics.Here for the first time an high power, high repetition rate, ultra short pulses, Yb doped fiber laser has been used jointly with a trepanning head to carry out hole trepanning trials in 900 µm thick stainless steel L316. Holes with aspect ratio up to 24 have been shown. Holes geometry has been characterized showing a profile which is cylindrical. The trepanning time has been optimized and reduced to 1.5 s. These results show not only the huge potential introduced in material hole trepanning by coupling high power, high repetition rate, fs laser with an innovative trepanning head but also pave the way for the application of laser trepanning in future fields such as automotive and microelectronics.

Flexible Dye Solar Cells (FDSCs), in their most widespread architecture, are assembled with two opposing planar films or foil substrates in metal–plastic or plastic–plastic combinations. The use of one metal electrode enables the convenient utilization of materials and high temperature processes but is accompanied by issues including partial opacity of the electrolyte and catalyst layer. Constraints on the stability of plastic substrates have led to the development of a variety of alternative material formulations and processes to guarantee performance even at low temperatures compatible with plastic films. Recently, efforts in doing without transparent conducting oxides have led to the development of new unconventional architectures. Review of the operation of DSCs shows that initial target markets are represented by indoor applications where power output densities have been shown to outperform competing flexible photovoltaic technologies. Whereas performance, stability in particular, needs to be significantly improved for the adoption in long term outdoor installations, commercial products integrating FDCSs for indoor or portable use have already been launched. Issues pertaining progress in materials, processes, devices and industrialization of FDSCs will be analyzed and discussed in this review.

In polluted areas, a major issue is the correct assessment of the exposure of general population to industrial pollutants. The objectives were: to evaluate the exposure to heavy metals emitted from the industrial area of Taranto; to correlate biological monitoring data with environmental data, in order to clarify the impact of industrial pollution in terms of internal dose. A cross sectional study has been designed to measure levels of urinary arsenic, lead, cadmium, chromium, manganese in 300 inhabitants of Taranto, Statte and Laterza. Adult subjects have been selected by a two-stage random stratified sampling. Results are based on 272 subjects (131 men and 141 women). The observed concentrations of metals in the whole study population are overall high. The median values for lead (7.4 μg/l) and chromium (0.4 μg/l) are higher than the 95° percentile of the range of reference values. For manganese and arsenic the 95° percentile of concentration in the whole study population is higher than the 95° percentile of the range of reference values. Concentrations of mercury in the whole study population are comparable to reference.

The National Environmental Remediation programme in Italy includes sites with documented contamination and associated potential health impacts (National Priority Contaminated Sites—NPCSs). SENTIERI Project, an extensive investigation of mortality in 44 NPCSs, considered the area of Taranto, a NPCS where a number of polluting sources are present. Health indicators available at municipality level were analyzed, that is, mortality (2003–2009), mortality time trend (1980–2008), and cancer incidence (2006-2007). In addition, the cohort of individuals living in the area was followed up to evaluate mortality (1998–2008) and morbidity (1998–2010) by district of residence. The results of the study consistently showed excess risks for a number of causes of death in both genders, among them: all causes, all cancers, lung cancer, and cardiovascular and respiratory diseases, both acute and chronic. An increased infant mortality was also observed from the time trends analysis. Mortality/morbidity excesses were detected in residents living in districts near the industrial area, for several disorders including cancer, cardiovascular, and respiratory diseases. These coherent findings from different epidemiological approaches corroborate the need to promptly proceed with environmental cleanup interventions. Most diseases showing an increase in Taranto NPCS have a multifactorial etiology, and preventive measures of proven efficacy (e.g., smoking cessation and cardiovascular risk reduction programs, breast cancer screening) should be planned. The study results and public health actions are to be communicated objectively and transparently so that a climate of confidence and trust between citizens and public institutions is maintained.

The optimisation study of the fabrication of a compact TiO2 blocking layer (via Spray Pyrolysis Deposition) for poly(3-hexylthiopene) (P3HT) for Solid State Dye Sensitized Solar Cells (SDSCs) is reported. We used a novel spray TiO2 precursor solution composition obtained by adding acetylacetone to a conventional formulation (Diisopropoxytitanium bis(acetylacetonate) in ethanol). By Scanning Electron Microscopy a TiO2 layer with compact morphology and thickness of around 100 nm is shown. Through a Tafel plot analysis an enhancement of the device diode-like behaviour induced by the acetylacetone blocking layer respect to the conventional one is observed. Significantly, the device fabricated with the acetylacetone blocking layer shows an overall increment of the cell performance with respect to the cell with the conventional one (ΔJsc/Jsc = +13.8%, ΔFF/FF = +39.7%, ΔPCE/PCE = +55.6%). A conversion efficiency optimum is found for 15 successive spray cycles where the diode-like behaviour of the acetylacetone blocking layer is more effective. Over three batches of cells (fabricated with P3HT and dye D35) an average conversion efficiency value of 3.9% (under a class A sun simulator with 1 sun A.M. 1.5 illumination conditions) was measured. From the best cell we fabricated a conversion efficiency value of 4.5% was extracted. This represents a significant increment with respect to previously reported values for P3HT/dye D35 based SDSCs.

28th European Photovoltaic Solar Energy Conference and Exhibition; 2761-2763, In this work, we present the application of platinum (Pt) electrodeposition (ED) over a large area flexible dye-sensitized solar cells (DSCs) counterelectrodes (CEs). The goal was solving the well-known uniformity problems of Pt deposition over resistive substrates [1], ensuring both high transparency and an effective catalytic activity, fundamental and contrasting requirements for devices based on metallic photoelectrodes (PEs). We successfully fabricated a DSC parallel module scaling the ED process up to 8x10cm2 area, by means of a conducting grid over the substrate. Interestingly, the same grid is also used as sealant in the module architecture. We also optimised the ED process parameters and obtained a transparent, homogeneous and catalytic Pt layer on ITOPEN substrates. By assembling this CE on a titanium (Ti) based PE, we obtained a parallel module with a power conversion efficiency of 2.7% on active area, using commercial available materials. To the best of our knowledge, this is the first functioning flexible DSC module using an electrodeposited Pt CE on plastic substrate and a TiO2- based PE on Ti foil.

in Taranto IPS (Italian polluted site, made up of 2 municipalities) the Decree defining site boundaries lists the presence of a refinery, a steel plant, a harbour area and waste landfills together with illegal dumping sites. Previous environmental and epidemiological investigations in the area documented the presence of environmental contamination and increased mortality from respiratory and cardiovascular diseases as well as a number of cancer sites; for these same health outcomes the cohort study of residents showed increased risk both in terms of mortality and morbidity.to describe the health status of residents in Taranto IPS analyzing different health indicators available at municipal level, i.e. mortality (2003-2009), mortality time trend (1980-2008) and cancer incidence (2006-2007).the analyses were carried out for residents in Taranto IPS. Mortality update (SENTIERI Project, 2003-2009) regards 63 single or grouped causes (all ages, both genders); for a selection of causes 0-1 and 0-14 age classes were analyzed (both genders combined). Standardized mortality ratio crude (SMR) and deprivation adjusted together with 90% confidence intervals (90%CI) were computed using regional rates for comparison. Mortality time trend (1980-2008, triennial intervals) were analyzed calculating standardized rates (0-99 years, both genders, per 100,000, Italian population at 2001 Census as reference) and 90%CI. Time trends were computed for all causes, all neoplasms (and lung cancer), cardiovascular diseases (and ischemic heart diseases), respiratory diseases (also acute and chronic) and all causes infant mortality (both genders combined). For cancer incidence (2006-2007) Standardized incidence ratio (SIR) and 90%CI were calculated for both genders; incidence rates of cancer registries of the macroarea South and Islands (2005-2007) and rates of Taranto Province excluding SIN municipalities (2006-2007) were used for comparison.in Taranto IPS mortality among men is in excess in both periods (SENTIERI Project 1995-2002 and 2003-2009) for all causes, all neoplasms (including lung and pleural cancer), dementia, cardiovascular diseases (including hypertension and ischemic heart diseases), respiratory diseases (including the acute ones) and digestive diseases (including liver cirrhosis). All causes infant mortality is in excess in both periods. Time trends show that Taranto IPS rates are higher than regional average in the majority of time intervals for most causes in both genders. Rates are often higher than national average form any triennial intervals. Among males, over the whole period, mortality in Taranto IPS is higher than regional and national average for causes as lung cancer, diseases of the respiratory system, including the chronic ones. Among females, since the early Nineties, lung cancer and ischemic heart diseases are in excess in Taranto IPS. Also infant mortality is higher for the whole period in Taranto IPS than regional and national averages. Cancer incidence results show excesses for cancer sites already indicated by mortality data.mortality analyzed in the context of SENTIERI Project (1995-2002 and 2003-2009), time trend mortality (1980-2008) and cancer incidence (2006- 2007) show, in both genders, excesses for causes for which an etiologic role of environmental exposure present in Taranto IPS are either ascertained or suspected on the basis of a priori evaluation of the epidemiological evidence. The finding of excess infant mortality is of the utmost importance in public health terms. Most diseases showing an increased risk have multifactorial etiology, therefore interventions of proven efficacy, such as smoking cessation, food education, measures for cardiovascular risk reduction and breast cancer and colon screening programmes should be planned. To build a climate of confidence and trust between citizens and public institutions study results and public health actions are to be communicated objectively and transparently.

We have carried out a systematic and combined I- V, electrochemical impedance spectroscopy (EIS), and scanning emission microscopy (SEM) investigation of dye solar cells (DSCs) fabricated with laser-sintered TiO2 photoanodes as a function of laser-integrated fluence Φ. We show that the electron lifetime τoc in the TiO2 film extracted from EIS spectra monotonically increases with laser sintering fluence both at constant illumination and, even more significantly, at constant photoinduced charge Qoc. The increase in τoc between the poorly sintered and the best laser-sintered devices is an order of magnitude at constant illumination (equivalent to the increase in device efficiency) and even greater at constant Qoc. A strong correlation between τoc and the cell electrical parameters is observed, although device efficiency peaks with Φ whereas τoc does not. The rise of τoc with Φ indicates improved electromechanical bonding between TiO2 nanoparticles due to the improved sintering carried out by the raster scanning laser process, as also confirmed by SEM images. The strong correlation between device performance and τoc indicates that laser processing may also have significant potential in many other device applications that require high-surface-area TiO2 coupled with good electronic transduction.

After the introduction in 1991 by B. O’Regan and M. Gratzel, Dye Solar Cells (DSCs) have reached power conversion efficiency values over small area device as high as 11%. Being manufactured with relatively easy fabrication processes often borrowed from the printing industry and utilizing low cost materials, DSC technology can be considered nowadays a proper candidate for a large scale production in industrial environment for commercial purposes. This scenario passes through some challenging issues which need to be addressed such as the set-up of a reliable, highly automated and cost-effective production line and the increase of large area panels performances, in terms of efficiency, stability and life-time of the devices. In this work, an overview of the most utilized DSCs materials and fabrication techniques are highlighted, and some of the most significant characterization methods are described. In this direction, different approaches used to improves devices performances are presented. In particular, several methods and techniques known as Light Management (LM) have been reported, based to the ability of the light to be confined most of the time in the cell structure. This behavior contributes to stimulate higher levels of charge generation by exploiting scattering and reflection effects. The use of diffusive scattering layers (SLs), nanovoids, photonic crystals (PCs), or photoanodes co-sensitization approaches consisting in the use of two Dyes absorbing in two different parts of the visible range, have been demonstrated to be effective strategies to carry out the highest values of device electrical parameters. Finally, to increase the light path inside the DSCs active layer, the use of refractive element on the topside (a complementary approach to SL) has been shown a promising possibility to further improve the generated photocurrent.

A geographic analysis of the causes of death is an important tool for assessing the effectiveness of Public Health initiatives. The aim of this study is to analyse the causes of death between 2000 and 2004, to discover any excess mortality from cancer in Province of Taranto, an area at high environmental risk.Mortality data from cancer were selected from the Puglia Regional Nominative Causes of Death Registry. Crude and standardized rates and Standardized Mortality Ratios (SMR) were calculated for the five Provinces of the Puglia Region, their capital cities and in four concentric rings around the industrial area located in Province of Taranto.. Even if the highest death rate for all tumours resulted in the Province of Lecce (24.9 x 10,000), in the cities of Lecce and Bari (29 x 10,000), the distribution of the SMRs in Province of Taranto showed an excess of mortality (+10%) in the ring next to industrial area. For lung cancer the highest rate was reported in city of Taranto (6 x 10,000) and the highest risk (+24%) in the ring next to industrial area. Moreover, in this area 9 (70%) of the 13 considered malignant tumours types presented an excess of mortality.The results uphold the data reported in the published literature. It is fundamental to intensify research into other risk factors (exposure at work and aberrant lifestyles). Moreover, there is an increasing need for a Regional Cancer Register.

Background. A geographic analysis of the causes of death is an important tool for assessing the effectiveness of Public Health initiatives. The aim of this study is to analyse the causes of death between 2000 and 2004, to discover any excess mortality from can- cer in Province of Taranto, an area at high environmental risk. Methods. Mortality data from cancer were selected from the Puglia Regional Nominative Causes of Death Registry. Crude and standardized rates and Standardized Mortality Ratios (SMR) were calculated for the five Provinces of the Puglia Region, their capital cities and in four concentric rings around the industrial area located in Province of Taranto. Results. Even if the highest death rate for all tumours resulted in the Province of Lecce (24.9 x 10,000), in the cities of Lecce and Bari (29 x 10,000), the distribution of the SMRs in Province of Taranto showed an excess of mortality (+10%) in the ring next to industrial area. For lung cancer the highest rate was reported in city of Taranto (6 x10,000) and the highest risk (+24%) in the ring next to industrial area. Moreover, in this area 9 (70%) of the 13 considered malignant tumours types presented an excess of mortality. Conclusion. The results uphold the data reported in the pub- lished literature. It is fundamental to intensify research into other risk factors (exposure at work and aberrant lifestyles). Moreover, there is an increasing need for a Regional Cancer Register., Journal of Preventive Medicine and Hygiene, Vol 50, No 3 (2009)

Scanning laser processing has become a useful and often used tool in thin film solar cell industries, since it enables precise, low cost, non-contact and highly automated fabrication processes such as scribing, patterning, marking, edge deletion, local melting and sintering. Dye Solar Cells (DSCs) are electrochemical photovoltaic devices representing an attractive technology for large area solar energy conversion since they utilize relatively cheap materials and simple manufacturing processes often “borrowed” from the printing industry. In this paper we show successful application of laser processing to this technology.

We present and experimentally test a simple model for difference frequency generation (DFG) in periodically-poled crystals with gaussian pumping beams. Focusing of input beams originates several non-collinear quasi-phase-matching configurations of the interacting wavevectors, which contribute to the idler output field. In this picture, we accurately describe a number of effects, such as the occurrence of annular idler intensity profiles and the asymmetric trend of DFG power vs temperature. Finally, we quantitatively test the model by means of an indirect measurement of the crystal poling period.

Nowadays, the relevance of ultrashort laser is well established for many medical or industrial applications. Indeed, the ultrashort laser technology has reached a high level of robustness which makes it compatible with the needs of industry. This laser technology combines the unique capacity to process any type of material with an outstanding precision and a minimal heat affected zone. Thanks to high average power and high repetition rate it is possible to achieve high throughput providing that the operating parameters are finely tuned to the application, otherwise heat accumulation and heat affected zone may appear. In this paper, the authors report on high throughput single pass ablation of stainless steel with a high average power Yb-doped fiber ultrashort pulse laser which is tunable in pulse duration from 350 fs to 10 ps and in repetition rate from 200 kHz to 2 MHz. The influence of pulse duration, repetition rate, fluence, energy dose, and scanning velocity will be discussed in terms of ablation eff...

Novel approaches for the fabrication of dye-sensitized solar cells (DSCs) are reported in which all the main constituent materials are processed by laser radiation. In addition to laser sintering of the nanocrystalline TiO2 film it is shown that lasers can be successfully utilized for nc-TiO2 film patterning, platinization of the counter-electrode, and efficient gasket sealing. All the mentioned processes are optimized and utilized for the fabrication of the first efficient and durable all-laser-based DSCs. Under one sun A.M. 1.5 illumination the power conversion efficiency (PCE) is 5.3% (6.2% unmasked) and also greater than or equal to the PCE of the cell fabricated with the same materials set but processed using conventional procedures (5.2%). These results open up a new scenario for DSC technology, i.e., that of setting up an entire, laser-based, three-step DSC pilot production line with tangible advantages in terms of effective processing, automation, large area scalability, and embedded energy.