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This preliminary work shows a new and innovative way to produce laser scribed reduced graphene oxide (LSGO) electrodes using different porous substrates (ranging from paper to plastic and fabric). The obtained electrodes were also tested as electrochemical sensors towards the detection of phosphate ions in water. To obtain the electrodes, a water suspension of GO was filtered on top of substrate (such as Whatman® filter paper) and a complete sensor was obtained from its reduction using a CO2 laser. The electrode is composed of working and counter electrodes made of LSGO and a reference electrode of a Ag/AgCl obtained by using a commercial AgCl conductive paste. Phosphate ions were detected by exploiting the reaction between molybdate and phosphate ions in acidic media (known in literature as molybdenum blue method). This chemical reaction produces the Keggin-type complex (PMo12O40)3-, that can be reduced under applied potential. The obtained results show that phosphate ions can be detected in a wide linear range, from 0.001 mM to 1mM, in presence of 1mM molybdate with a very satisfying selectivity. We also tried to pre-treatment the paper substrate with acidic molybdate ions in order to obtain a ready-made sensor directly usable for the detection of phosphate ions in situ avoiding any kind of real sample manipulation For this aim, the paper substrate was soaked with sulphuric acid and molybdate solution and dried in order to desorb these chemicals directly into the water sample to be analyzed. Preliminary results, shows that the process of absorption and desorption can be carried out by optimizing the volume and concentration of the absorbed solution and thus can be used to obtain a portable, easy to use and fast phosphate sensor for in situ and real time monitoring of water quality.

Nitrogen, in the forms of nitrate (NO3-), nitrite, or ammonium, is a nutrient needed for plant growth and it is a common constituent of fertilizers [1]. When fertilizers are overused, they contaminate the ground water and then the food chain. For humans, a low level of nitrate is advisable because it increases the blood flow and has a good effect on both blood pressure and cardiovascular system. On the contrary, a high concentration of nitrate can be dangerous for humans. Nitrate ions undergoes different chemical transformations (i.e. to nitrite ions by Escherichia coli) producing different nitrogen-based compound such as nitrite ions, nitric oxide and ammonia [2]. These chemicals lead to several problems such as cancer, neurodegenerative disease and gastritis. Furthermore, nitrate ions are responsible of the blu-baby disease because they oxide hemoblogin to methemoglobine which has a lower capability to transport oxygen [3]-[4]. Considering all these hazards, the Environmental Protection Agency (EPA) has fixed the maximum allowed concentration of nitrates in drinking water to 44 ppm [5]. Nowadays, nitrate ions quantification is performed by spectroscopy ensuring Limit Of Detection (LOD) in the ppb range [6]-[7]. However, this technique consists of hard procedure (conversion of nitrates to nitrite using cadmium or zinc salts) and requires skilled personnel. Furthermore, it lacks of sensitivity when coloured or opaque samples are analysed. Such disadvantages confine this technique to a lab-based analysis making impossible to detect nitrate ions in real time and/or in situ.

Dopamine (DA) is one of the most important neurotransmitters that influences the processes that involve memory, sleep, mood, learning among others [1]. In fact, in the last years, dopamine concentration in human body fluids has been related to some neurodegenerative diseases, such as Parkinson and Alzheimer's diseases [2]. The possibility to have a bio-marker for these disease is of extreme importance because, disease related with dementia, are diagnosed when they are already developed and their management become almost impossible. The possibility to continuously monitor DA level in fluids, such as blood and urine, could accelerate the early diagnosis of these diseases. The principal analytical method to detected dopamine is High Pressure Liquid Chromatrography (HPLC), but this technique does not allow any kind of real time or in situ analysis and, furthermore, is highly expensive and hard to use [3] - [4]. To achieve a real-time screening of DA, electrochemical sensors are perfect candidates [5]. In this work we show the preliminary results concerning the development and the optimization of a flexible and cheap electrochemical DA sensor. The active material of sensors is based on reduced graphene oxide with Au nanoparticles (NPs) and was obtained by co-electrodeposition into a ITO-PET substrate. The electrodeposition parameters have been optimized in order to increase the DA peak in Phosphate Buffer Solution (PBS) and obtain a Limit Of Detection (LOD) in the nM range. A very wide linear range (0.1-30 μM) and a low LOD, down to 50 nM, have been found. The main issue to electrochemically detect dopamine concern the presence of other compounds able to react on the surface of the electrode, leading overlapping peak [6-9]. Ascorbic acid (AA) and Uric Acid (UA), two of these interference species, have oxidation peak of about 0.1 V and 0.4 V, respectively [10]. Furthermore, in biological samples, these chemicals are present in a concentration range of about 100-1000 times higher than dopamine one, making this issue even more challenging [10]. We found by voltammetry studies that in presence of all these chemicals (AA,UA and DA) DA can be still detected. Moreover, we found that is possible to use our electrode to quantify even UA at low concertation. In order to validate the technology, the sensor was also tested using synthetic urine and cerebrospinal fluid, from a patient with alcoholic neuropathy. Excitingly, we have found that both these matrixes don't interfere with DA detection (or in a negligible way). The results of this work are so really promising and thrilling because can allow a in-situ, low cost and real time screening of DA to permits early diagnosis of different diseases.

In this work we present innovative lead-acid batteries with nanostructured electrodes, which are cycled in a wide range of temperatures typically of lead-acid commercial batteries (EN 61427-1: 2013). In comparison to parameters usually used to commercial batteries, much more stressful conditions in terms of cut-off, charge/discharge rate and discharge were imposed.

Electrodeposition is a convenient technique for the development of low cost materials for photovoltaic (PV) device processing. Using a single step electrodeposition route, several groups have fabricated CIS (CuInSe) and CIGS (CuInGaSe) films [1]. One of the most important requirements for successful application of one-step electrodeposition film formation, is the ability to control composition of the deposited films and to develop polycrystalline microstructures with a low surface roughness and high sintered density. In this preliminary work, CIS films were produced by single bath electrodeposition finding the optimal conditions in order to achieve a dense film with high crystallinity and uniform, flat surfaces, which are of critical importance for photovoltaic applications. Electrodeposition was carried out in the potentiostatic mode using a conventional three-electrode configuration.

This work presents our preliminary results regarding an electrochemical process which allows the growth of nanostructured materials by means of nanopore templates. Also we analyze possible applications of this process to fabricate nanostructured semiconductors, such as CIGS, suitable for photovoltaic devices, and we consider the implications from the perspective of characterization techniques and device modelling when using such a technology.