A carregar...
Projeto de investigação
Not Available
Financiador
Autores
Publicações
Application of Covalent Organic Frameworks (COFs) as Dyes and Additives for Dye-Sensitized Solar Cells (DSSCs)
Publication . Inácio, Diogo; Pinto, Ana Lúcia; Paninho, Ana B.; Branco, Luís C.; Freitas, Sunny K. S.; Cruz, Hugo; LAQV@REQUIMTE; DQ - Departamento de Química; MDPI AG
Five Covalent Organic Frameworks (COFs) were synthesized and applied to Dye-Sensitized Solar Cells (DSSCs) as dyes and additives. These porous nanomaterials are based on cheap, abundant commercially available ionic dyes (thionin acetate RIO-43, Bismarck brown Y RIO-55 and pararosaniline hydrochloride RIO-70), and antibiotics (dapsone RIO-60) are used as building blocks. The reticular innovative organic framework RIO-60 is the most promising dye for DSSCs. It possesses a short-circuit current density (Jsc) of 1.00 mA/cm2, an open-circuit voltage (Voc) of 329 mV, a fill factor (FF) of 0.59, and a cell efficiency (η) of 0.19%. These values are higher than those previously reported for COFs in similar devices. This first approach using the RIO family provides a good perspective on its application in DSSCs as a dye or photoanode dye enhancer, helping to increase the cell’s lifespan.
Understanding the Absorption of Fluorinated Gases in Fluorinated Ionic Liquids for Recovering Purposes Using Soft-SAFT
Publication . Ferreira, Margarida L.; Araújo, João M. M.; Vega, Lourdes F.; Pereiro, Ana B.; LAQV@REQUIMTE; DQ - Departamento de Química; ACS - American Chemical Society
It is proven that fluorinated gases (F-gases) have a vast impact on climate change due to their high global warming potential. Hence, it is imperative to search for new molecules to replace them in current applications, as well as technologies to capture, recover, and recycle F-gases to avoid their emissions to the atmosphere. One of the attractive technologies for this purpose is to absorb them in fluorinated ionic liquids (FILs), given their solubilization power. However, the complexity of FILs and the time-consuming experimental methodologies to fully characterize them hinder their prompt usage in this urgent field. In this work, the soft-Statistical Associating Fluid Theory (soft-SAFT) Equation of State is used as a tool to investigate the solubility of six different F-gases (R-32, R-125, R-134a, R-14, R-116, R-218) in five FILs ([C2C1Im][C4F9SO3], [C2C1Im][C4F9CO2], [C2C1py][C4F9SO3], [C2(C6F13)C1Im][N(CF3SO2)2], and [C2(C6F13)C1Im][N(C2F5SO2)2]). The robustness of the soft-SAFT approach allowed the establishment of new FIL models in a simple and fast way, and the calculation of F-gases solubility in them, in excellent agreement with existing experimental data. Once the models were assessed, a systematic study was performed regarding the structural features of FILs favoring their performance to absorb F-gases by using the soft-SAFT approach as a screening tool. It has been obtained that the solubility is favored by the presence of a perfluoroalkyl chain in the imidazolium cation, together with a bulkier anion. In all cases, [C2(C6F13)C1Im][N(C2F5SO2)2] shows a superior solubility of F-gases than the [C2(C6F13)C1Im][N(CF3SO2)2], also indicating that the addition of one carbon to the two anionic symmetric fluorinated chains contributes to the gas-philicity of the FILs. This work proves the relevance of using the soft-SAFT framework to obtain insights into the behavior of such complex systems and key trends, even when experimental data are scarce, as a step forward in assessing systems for separating and recovering F-gases.
Triazaphosphaadamantane-functionalized terpyridine metal complexes
Publication . Librando, Ivy L.; Paul, Anup; Mahmoud, Abdallah G.; Gurbanov, Atash V.; Carabineiro, Sónia A. C.; Silva, M. Fátima C. Guedes da; Geraldes, Carlos F. G. C.; Pombeiro, Armando J. L.; LAQV@REQUIMTE; DQ - Departamento de Química; RSC - Royal Society of Chemistry
In accordance with UN's Sustainable Development Goal (UN's SDG) 12 which encompasses the sustainable use of chemical products and a sound circular economy, this work is focused on the synthesis of Co(II), Ni(II) and Mn(II) complexes bearing combined 1,3,5-triaza-7-phosphaadamantane and benzyl terpyridine core moieties (PTA–Bztpy) as ligand, followed by their evaluation as catalysts for the microwave-assisted cyclohexane oxidation using tert-butyl hydroperoxide (TBHP) as oxidant. The most active catalyst, with a manganese metal center, was heterogenized on six different carbon materials. The results disclosed the influence of several reaction parameters, such as catalyst loading, temperature, reaction time and solvent, on the catalytic activity and selectivity of the homogeneous and carbon-supported catalysts. Recyclability of the carbon-supported catalyst allowed facile separations, recovery and reuse for five consecutive cycles.
Bioactivity of Ionic Liquids Based on Valproate in SH-SY5Y Human Neuroblastoma Cell Line
Publication . Dias, Ana Rita; Ferraz, Ricardo; Costa-Rodrigues, João; Santos, Andreia F. M.; Jacinto, Manuel L.; Prudêncio, Cristina; Noronha, João Paulo; Branco, Luis C.; Petrovski, Zeljko; DQ - Departamento de Química; LAQV@REQUIMTE; MDPI - Multidisciplinary Digital Publishing Institute
The search for alternative and effective therapies to fight cancer is one of the main goals of the pharmaceutical industry. Recently, ionic liquids (ILs) have emerged as potential therapeutic agents with antitumor properties. The goal of this study was to synthesize and evaluate the bioactivity of different ILs coupled with the active pharmaceutical ingredient (API) valproate (VPA) as an antitumor agent. The toxicity of the prepared ionic liquids was evaluated by the MTT cell metabolic assay in human neuroblastoma SH-SY5Y and human primary Gingival Fibroblast (GF) cell lines, in which they showed inhibitory effects during the study period. In addition, low cytotoxicity against GF cell lines was observed, suggesting that these compounds are not toxic to human cell lines. [C2OHDMiM][VPA] demonstrated an outstanding antitumor activity against SH-SY5Y and lower activity against the non-neoplastic GF line. The herein assessed compounds played an important role in the modulation of the signaling pathways involved in the cellular behavior. This work also highlights the potential of these ILs-API as possible antitumor agents
Bioelectrochemical systems (BESs) for agro-food waste and wastewater treatment, and sustainable bioenergy
Publication . Ramanaiah, S. V.; Chandrasekhar, K.; Cordas, Cristina M.; Potoroko, Irina; LAQV@REQUIMTE; DQ - Departamento de Química; Elsevier
Producing food by farming and subsequent food manufacturing are central to the world's food supply, accounting for more than half of all production. Production is, however, closely related to the creation of large amounts of organic wastes or byproducts (agro-food waste or wastewater) that negatively impact the environment and the climate. Global climate change mitigation is an urgent need that necessitates sustainable development. For that purpose, proper agro-food waste and wastewater management are essential, not only for waste reduction but also for resource optimization. To achieve sustainability in food production, biotechnology is considered as key factor since its continuous development and broad implementation will potentially benefit ecosystems by turning polluting waste into biodegradable materials; this will become more feasible and common as environmentally friendly industrial processes improve. Bioelectrochemical systems are a revitalized, promising biotechnology integrating microorganisms (or enzymes) with multifaceted applications. The technology can efficiently reduce waste and wastewater while recovering energy and chemicals, taking advantage of their biological elements' specific redox processes. In this review, a consolidated description of agro-food waste and wastewater and its remediation possibilities, using different bioelectrochemical-based systems is presented and discussed together with a critical view of the current and future potential applications.
Unidades organizacionais
Descrição
Palavras-chave
Contribuidores
Financiadores
Entidade financiadora
Fundação para a Ciência e a Tecnologia
Programa de financiamento
DL 57/2016
Número da atribuição
dl 57/2016/CP1364/CT0010