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The outstanding physical properties of dots-in-host (QD@Host) hetero semiconductors demand detailed methods to fundamentally understand the best routes to optimize their potentialities for different applications. In this work, a 4-band k.p-based method was developed for rocksalt QDs that describes the complete optical properties of arbitrary QD@Host systems, trailblazing the way for the full opto-electronic analysis of quantum-structured solar cells. Starting with the determination of the QD bandgap, and validation against well-established literature results, the electron transition rate is then computed and analysed against the main system parameters. This is followed by a multi-parameter optimization, considering intermediate band solar cells as a promising application, where the best QD configuration was determined, together with the corresponding QD@Host absorption spectrum, in view of attaining the theoretical maximum efficiency (~ 50%) of this photovoltaic technology. The results show the creation of pronounced sub-bandgap absorption due to the electronic transitions from/to the quantum-confined states, which enables a much broader exploitation of the sunlight spectrum.

Funding Information: S. Goswami would like to thank to Lisboa2020 Programme, Centro 2020 programme, Portugal 2020, European Union, through the European Social Fund who supported LISBOA-05-3559-FSE-000007 and CENTRO-04-3559-FSE-000094 operations as well as to Fundação para a Ciência e Tecnologia (FCT) and Agência Nacional de Inovação (ANI). Publisher Copyright: © 2022 The Authors Polymer material provides significant advantages over the conventional inorganic material-based electronics due to its attractive features including miniaturized dimension and feasible improvisations in physical properties through molecular design and chemical synthesis. In particular, conjugate polymers are of great interest because of their ability to control the energy gap and electronegativity through molecular design that has made possible the synthesis of conducting polymers with a range of ionization potentials and electron affinities. Polyaniline (PANI) is one of the most popular conjugated polymers that has been widely explored so far for its multifunctionality in diverse potential applications. This review is focusing on the recent advances of PANI for smart energy applications including supercapacitors, batteries, solar cells and nanogenerators and the development in its synthesis, design, and fabrication processes. A details investigation on the different types of chemical process has been discussed to fabricate PANI in nanostructures, film, and composites form. The paper includes several studies which are advantageous for understanding: the unique chemical and physical properties of this polymer; and the easily tunable electrical properties along with its redox behavior; and different processes to develop nanostructures, film, or bulk form of PANI that are useful to derive its applicability in smart objects or devices. publishersversion published

Funding Information: This study was financed in part by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001. The authors would like to thank the financial support given by CNPq—National Council for Scientific and Technological Development (Grant Nos. 402287/2013–4, 304044/2019–9, and 442575/2019–0), SISNANO/MCTI, Financier of Studies and Projects (FINEP) and Brazilian Agricultural Research Corp. (Embrapa) AgroNano research network. The authors would like to acknowledge the European Commission under the Project NewFun (Grant No. ERC-StG-2014, GA 640598). This work was also supported by European Research Council (ERC) Advanced Grant DIGISMART (Grant No. ERC-AdG-2017, GA 787410) and the FEDER funds through the COMPETE 2020 Program and the National Funds through the FCT—Portuguese Foundation for Science and Technology under the Project No. POCI-01–0145-FEDER-007688, Reference UID/CTM/50025; Project CHIHC, Grant No. PTDC/NAN-MAT/32558/2017; and Project BEST, Grant Nos. ALT20–03-0247-FEDER-113469 and LISBOA-01–0247-FEDER-113469. J. C. acknowledges the Santander/NOVA 2021 Collaborative Research Award—Graphene Smart Bandages for Diabetic Foot Ulcer Monitoring, Reference GSBDFULM. P. C. acknowledges BI-84-Mestre-DIGISMART and CAPES/Embrapa (Grant No. 88882.157024/2017 01) for the scholarships received. S. S. and T. P. also acknowledge the funding from National Foundation for Science and Technology, through the Ph.D. Grant Nos. SFRH/BD/149751/2019 and 2020.08606.BD. Publisher Copyright: © 2022 Author(s). Since the discovery of laser-induced graphene (LIG), significant advances have been made to obtain green LIG (gLIG) from abundant, eco-friendly, natural, and organic renewable bio-based carbon sources. Recently, some sustainable and cost-effective electronic devices have been designed with gLIG, resulting in diverse solutions to the environmental impact caused by electronic waste (e-waste). However, there are still several challenges that must be addressed regarding the widespread market implementation of gLIG-based products, from synthesis to practical applications. In this review, we focus on sustainable precursor sources, their conversion mechanisms, physical and chemical properties and applications, along with the challenges related to its implementation, showing the future opportunities and perspectives related to this promising new material. Various systems based on gLIG for energy storage, electrocatalysis, water treatment, and sensors have been reported in the literature. Additionally, gLIG has been proposed for ink formulation or incorporation into polymer matrices, to further expand its use to non-carbon-based substrates or applications for which pristine LIG cannot be directly used. In this way, it is possible to apply gLIG on diverse substrates, aiming at emerging wearable and edible electronics. Thus, this review will bring an overview of gLIG developments, in accordance with the European Green Deal, the United Nations Sustainable Development Goals and the new era of internet-of-things, which demands cost-effective electronic components based on the principles of energy efficiency and sustainable production methods. publishersversion published

LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB Publisher Copyright: © 2022 by the authors. FucoPol is an acylated polysaccharide with demonstrated valuable functional properties that include a shear thinning fluid behaviour, a film-forming capacity, and an emulsion forming and stabilizing capacity. In this study, the different conditions (concentration, temperature, and time) for alkaline treatment were investigated to deacylate FucoPol. Complete deacetylation and desuccinylation was achieved with 0.02 M NaOH, at 60 °C for 15 min, with no significant impact on the biopolymer’s sugar composition, pyruvate content, and molecular mass distribution. FucoPol depyruvylation by acid hydrolysis was attempted, but it resulted in a very low polymer recovery. The effect of the ionic strength, pH, and temperature on the deacetylated/desuccinylated polysaccharide, d-FucoPol, was evaluated, as well as its emulsion and film-forming capacity. d-FucoPol aqueous solutions maintained the shear thinning behaviour characteristic of FucoPol, but the apparent viscosity decreased significantly. Moreover, contrary to FucoPol, whose solutions were not affected by the media’s ionic strength, the d-FucoPol solutions had a significantly higher apparent viscosity for a higher ionic strength. On the other hand, the d-FucoPol solutions were not affected by the pH in the range of 3.6–11.5, while FucoPol had a decreased viscosity for acidic pH values and for a pH above 10.5. Although d-FucoPol displayed an emulsification activity for olive oil similar to that of FucoPol (98 ± 0%) for an oil-to-water ratio of 2:3, the emulsions were less viscous. The d-FucoPol films were flexible, with a higher Young′s modulus (798 ± 152 MPa), a stress at the break (22.5 ± 2.5 MPa), and an elongation at the break (9.3 ± 0.7%) than FucoPol (458 ± 32 MPa, 15.5 ± 0.3 MPa and 8.1 ± 1.0%, respectively). Given these findings, d-FucoPol arises as a promising novel biopolymer, with distinctive properties that may render it useful for utilization as a suspending or emulsifier agent, and as a barrier in coatings and packaging films. publishersversion published

Laser irradiation of polymeric materials has drawn great attention as a fast, simple, and cost-effective method for the formation of porous graphene films that can be subsequently fabricated into low-cost and flexible electronic and energy-storage devices. In this work, we report a systematic study of the formation of laser-induced graphene (LIG) with sheet resistances as low as 9.4 Ω/sq on parylene-C ultrathin membranes under a CO

Funding Information: The authors acknowledge the financial support of EU-Horizon 2020 (Symbiotic, FET-Open, GA665046), and from national funds from FCT - Fundação para a Ciência e a Tecnologia, I.P., in the scope of the projects LA/P/0037/2020, UIDP/50025/2020, UIDB/50025/2020 and UID/EMS/00532/2019. Nádia Ferreira (SFRH/BD/122955/2016), Liliana Carneiro (SFRH/BD/122954/2016), and Ana Carolina Marques (SFRH/BD/115173/2016) acknowledge Fundação para a Ciência e Tecnologia (FCT) for financial support. Publisher Copyright: © 2022 The Author(s) This work describes an innovative electrochemical biosensor that advances its autonomy toward an equipment-free design. The biosensor is powered by a passive direct methanol fuel cell (DMFC) and signals the response via an electrochromic display. Briefly, the anode side of the DMFC power source was modified with a biosensor layer developed using molecularly imprinted polymer (MIP) technology to detect sarcosine (an amino acid derivative that is a potential cancer biomarker). The biosensor layer was anchored on the surface of the anode carbon electrode (carbon black with Pt/Ru, 40:20). This was done by bulk radical polymerization with acrylamide, bis-acrylamide, and vinyl phosphonic acid. This layer selectively interacted with sarcosine when integrated into the passive DMFC (single or multiple, in a stack of 4), which acted as a transducer element in a concentration-dependent process. Serial assembly of a stack of hybrid DMFC/biosensor devices triggered an external electrochromic cell (EC) that produced a colour change. Calibrations showed a concentration-dependent sarcosine response from 3.2 to 2000 µM, which is compatible with the concentration of sarcosine in the blood of prostate cancer patients. The final DMFC/biosensor-EC platform showed a colour change perceptible to the naked eye in the presence of increasing sarcosine concentrations. This colour change was controlled by the DMFC operation, making this approach a self-controlled and self-signalling device. Overall, this approach is a proof-of-concept for a fully autonomous biosensor powered by a chemical fuel. This simple and low-cost approach offers the potential to be deployed anywhere and is particularly suitable for point-of-care (POC) analysis. publishersversion published

info:eu-repo/semantics/publishedVersion

Funding Information: This work was supported by Fundação para a Ciência e Tecnologia, Ministério da Ciência, Tecnologia e Ensino Superior (FCT-MCTES), through the grant number PTDC/QUI/64248/2006 (to A.S.P.), the Radiation Biology and Biophysics Doctoral Training Programme—RaBBiT (PD/00193/2012), Applied Molecular Biosciences Unit—UCIBIO (UIDP/04378/2020, i4HB—Institute for Health and Bioeconomy (LA/P/0140/2020) and CEFITEC (UIDB/00068/2020). A.V.A. (PD/BD/135477/2017 and COVID/BD/152498/2022) is supported by the RaBBiT programme. This work benefited from STSM funding by COST Action (CA15126 MOBIEU) and by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. Publisher Copyright: © 2022 by the authors. Encapsulins are protein nanocages capable of harboring smaller proteins (cargo proteins) within their cavity. The function of the encapsulin systems is related to the encapsulated cargo proteins. The Myxococcus xanthus encapsulin (EncA) naturally encapsulates ferritin-like proteins EncB and EncC as cargo, resulting in a large iron storage nanocompartment, able to accommodate up to 30,000 iron atoms per shell. In the present manuscript we describe the binding and protection of circular double stranded DNA (pUC19) by EncA using electrophoretic mobility shift assays (EMSA), atomic force microscopy (AFM), and DNase protection assays. EncA binds pUC19 with an apparent dissociation constant of 0.3 ± 0.1 µM and a Hill coefficient of 1.4 ± 0.1, while EncC alone showed no interaction with DNA. Accordingly, the EncAC complex displayed a similar DNA binding capacity as the EncA protein. The data suggest that initially, EncA converts the plasmid DNA from a supercoiled to a more relaxed form with a beads-on-a-string morphology. At higher concentrations, EncA self-aggregates, condensing the DNA. This process physically protects DNA from enzymatic digestion by DNase I. The secondary structure and thermal stability of EncA and the EncA−pUC19 complex were evaluated using synchrotron radiation circular dichroism (SRCD) spectroscopy. The overall secondary structure of EncA is maintained upon interaction with pUC19 while the melting temperature of the protein (Tm) slightly increased from 76 ± 1 °C to 79 ± 1 °C. Our work reports, for the first time, the in vitro capacity of an encapsulin shell to interact and protect plasmid DNA similarly to other protein nanocages that may be relevant in vivo. publishersversion published