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In article number 1805279, Luis Pereira and co‐workers demonstrate how to implement chiral nematic films from cellulose nanocrystals into transistors that are capable of circular polarized light detection. The resulting devices effectively use the cellulose films simultaneously as gate dielectrics and photonic filters. Right‐handed circular polarized light is transmitted and excites the semiconductor giving rise to distinct photocurrents from left‐handed radiation. publishersversion published

This research was funded by FEDER funds through the COMPETE 2020 Programme and National Funds through FCT-Portuguese Foundation for Science and Technology under project number POCI-01-0145-FEDER-007688, Reference UID/CTM/50025. J.D. acknowledges funding received from the European Union's Horizon 2020 Research and Innovation Programme through the project HERACLES (Project No. 700395) and the German Science Foundation through the collaborative research center SFB 595 (Electrical Fatigue of Functional Materials). A. Kiazadeh acknowledges FCT for the postdoctoral grant SFRH/BPD/99136/2013 and for funding received through the project NeurOxide (PTDC/NAN-MAT/30812/2017). Multi-level resistive switching characteristics of a Cu₂O/Al₂O₃ bilayer device are presented. An oxidation state gradient in copper oxide induced by the fabrication process was found to play a dominant role in defining the multiple resistance states. The highly conductive grain boundaries of the copper oxide-an unusual property for an oxide semiconductor-are discussed for the first time regarding their role in the resistive switching mechanism. publishersversion published

Entrevista a Elvira Fortunato: Vice-Reitora da Universidade NOVA de Lisboa. Parte II. Faces de Eva. Estudos sobre a Mulher. Faces de Eva. Estudos sobre a Mulher. 2019, n.41, pp.146-150. ISSN 0874-6885, Entrevista a Elvira Fortunato, Professora Catedrática e Vice-reitora da Universidade Nova de Lisboa, com enfoque no seu percurso profissional e de vida.

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The development of Rapid Diagnostic Tests (RDTs) for malaria diagnosis is an area of intense research. Here, we describe two nanoimmunoassays for malaria parasite detection; one based on agarose gel electrophoresis; and another employing lab-onpaper technology. Both nanoimmunoassays use gold nanoparticles (AuNPs) functionalized with 11-mercaptoundecanoic acid (MUA) or with the pentapeptide CALNN, and further conjugated with a monoclonal antibody (anti- PfHRP2) that specifically recognizes Plasmodium falciparum Histidine Rich Protein 2 (PfHRP2) antigen. The formation of AuNP-anti-PfHRP2 bionanoconjugates was confirmed by agarose gel electrophoresis, demonstrating that AuNP functionalization and mode of conjugation (by physiosorption or by chemical cross-linking) control antibody binding to AuNP. The agarose gel-based nanoimmunoassay showed that AuNP-MUA-anti- PfHRP2 bionanoconjugates could detect an antigen concentration of 12 μg/mL, one order of magnitude less than that detected by AuNPCALNN- anti-PfHRP2 bionanoconjugates (700 μg/mL). AuNP-MUA-anti-PfHRP2 bionanoconjugates were also shown to be effective for direct colorimetric detection of the antigen by Western Blot, eliminating the need for a secondary antibody. The lab-on-paper technology-based RDT was developed on a filter cellulose filter paper-based strip, eliminating the traditional plastic casing. The amount of bionanoconjugates, and the components in test and control lines were optimized. In the future, our goal is to apply this RDT in the analysis of clinical samples., Anais do Instituto de Higiene e Medicina Tropical, v. 14 (2015): 3º CONGRESSO NACIONAL DE MEDICINA TROPICAL & 1º CONGRESSO LUSÓFONO DE DOENÇAS TRANSMITIDAS POR VETORES

International audience

This study reports on the qualitative analysis of photoluminescence effect generated from waste carbon of cooking oven by facile cost-effective material engineering. The waste carbon product as a form of carbon nanoparticles (CNPs) is incorporated within a conjugate polymer, namely, polyaniline (PANI) to produce CNP-PANI composites that have shown excitation-wavelength-independent triple-band photoluminescence emission effect and highly sensitive Fe+3 ion detection ability. Herein the waste carbon material, while functionalized within the conjugated polymer, needs no further acid treatment or surface modification thus making the process cheaper, environmentally benign, and useful for green nanotechnology. The excitation-wavelength-independent unique triple-band photoluminescence spectrum is the direct consequence of carbon-polyaniline synergy in pi-pi transition and the surface passivation of CNPs by the -NH2 group rich aniline during in-situ polymerization. The current scenario has been studied for the samples prepared with different CNP concentrations for different reaction times and discussed in details with supportive physico-chemical characterizations. Moreover, the present study has demonstrated that the current material can be used as a fluorescent sensing platform for Fe+3 ions with high sensitivity and selectivity criteria where the detection limit of the sensing probe has a value as low as 12 x 10(-9) nM. proof published

The copper zinc tin sulfide (CZTS) compound is a promising candidate as an alternative absorber material for thin-film solar cells. In this study, we investigate the direct formation of Cu1.92ZnSnx(Sb1-x)S-4 compounds [CZT(A)S], with x = 1, 0.85, 0.70, and 0.50, via a mechanochemical synthesis (MCS) approach, starting from powders of the corresponding metals, zinc sulfide, and sulfur. The thermal stability of the CZT(A)S compounds was evaluated in detail by in situ synchrotron high-energy x-ray diffraction measurements up to 700 degrees C. The CZT(A)S compounds prepared via MCS revealed a sphalerite-type crystal structure with strong structural stability over the studied temperature range. The contribution of the MCS to the formation of such a structure at room temperature is analyzed in detail. Additionally, this study provides insights into the MCS of CZTS-based compounds: the possibility of a large-scale substitution of Sn by Sb and the production of single phase CZT(A)S with a Cupoor/Zn-poor composition. A slight increase in the band gap from 1.45 to 1.49-1.51 eV was observed with the incorporation of Sb, indicating that these novel compounds can be further explored for thin-film solar cells. info:eu-repo/semantics/publishedVersion

PTDC/CTM-ENE/5125/2014 PTDC/CTM-NAN/2912/2014 SFRH/BPD/115566/2016 SFRH/BPD/114833/2016 A novel generation of flexible opto-electronic smart applications is now emerging, incorporating photovoltaic and sensing devices driven by the desire to extend and integrate such technologies into a broad range of low cost and disposable consumer products of our everyday life and as a tool to bring together the digital and physical worlds. Several flexible polymeric materials are now under investigation to be used as mechanical supports for such applications. Among them, cellulose, the most abundant organic polymer on the Earth, commonly used in the form of paper, has attracted much research interest due to the advantages of being recyclable, flexible, lightweight, biocompatible and extremely low-cost, when compared to other materials. Cellulose substrates can be found in many forms, from the traditional micro-cellulose paper used for writing, printing and food/beverage packaging (e.g. liquid packaging cardboard), to the nano-cellulose paper which has distinct structural, optical, thermal and mechanical properties that can be tailored to its end use. The present article reviews the state-of-the-art related to the integration and optimization of photonic structures and light harvesting technologies on paper-based platforms, for applications such as Surface Enhanced Raman Scattering (SERS), supporting remarkable 107 signal enhancement, and photovoltaic solar cells reaching ∼5% efficiency, for power supply in standalone applications. Such paper-supported technologies are now possible due to innovative coatings that functionalize the paper surfaces, together with advanced light management solutions (e.g. wave-optical light trapping structures and NIR-to-visible up-converters). These breakthroughs open the way for an innovative class of disposable opto-electronic products that can find widespread use and bring important added value to existing commercial products. By making these devices ubiquitous, flexible and conformable to any object or surface, will also allow them to become part of the core of the Internet of Things (IoT) revolution, which demands systems' mobility and self-powering functionalities to satisfy the requirements of comfort and healthcare of the users. authorsversion published