8 documents found, page 1 of 1
Stable cellulose-based carbon molecular sieve membranes with very high selectiv...
Tiago Araújo; Márcia Andrade; Gabriel Bernardo; Adélio MendesCarbon molecular sieve membranes (CMSMs) with a remarkable separation performance and stability were prepared from an ionic liquid regenerated cellulose precursor. Extremely high selectivities to H2 and CO2 are reported (H2/CH4 > 206 000 and CO2/CH4 > 14 600) due to the precise pore size of the produced membranes. Selectivity results >3590 are reported for the first time for the C3H6/C3H8 separation using cellu...
Propane selective carbon adsorbents from phenolic resin precursor
Márcia Andrade; Andrew Parnell; Gabriel Bernardo; Adélio MendesNovel carbon adsorbents for propane/propylene separation, with an unprecedented adsorption selectivity to propane - the minority component - were prepared from a phenolic resin precursor. The preparation conditions of the carbon molecular sieve adsorbents, such as pre-treatment with phosphoric acid, carbonization and posttreatment with propylene, were carefully investigated concerning their role on the separati...
Graded Morphologies and the Performance of PffBT4T-2OD:PC71BM Devices Using Add...
Hugo Gaspar; Andrew Parnell; Gabriel Pérez; Júlio Viana; Stephen King; Adélio Mendes; Luiz Pereira; Gabriel BernardoThe impact of several solvent processing additives (1-chloronaphthalene, methylnaphthalene, hexadecane, 1-phenyloctane, and p-anisaldehyde), 3% v/v in o-dichlorobenzene, on the performance and morphology of poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3'-di(2-octyldodecyl)-2,2 ',5 ',22033,5 '',2'-quaterthiophen-5,5'-diyl)] (PffBT4T-2OD):[6,6]-phenyl-C71-butyric acid methyl ester (PC71BM)-based poly...
Progress in Upscaling Organic Photovoltaic Devices
Gabriel Bernardo; Lopes, T.; David Lidzey; Adélio MendesOrganic photovoltaic (OPV) cells have recently undergone a rapid increase in power conversion efficiency (PCE) under AM1.5G conditions, as certified by the National Renewable Energy Laboratory (NREL), which have jumped from 11.5% in October 2017 to 18.2% in December 2020. However, the NREL certified PCE of large area OPV modules is still lagging far behind (11.7% in July 2020). Additionally, there has been a ra...
Recent advances in membrane technologies for hydrogen purification
Gabriel Bernardo; Araujo, T.; da Silva Lopes, T.; J. M. Sousa; Adélio MendesPlanet Earth is facing accelerated global warming due to greenhouse gas emissions from human activities. The United Nations agreement at the Paris Climate Conference in 2015 highlighted the importance of reducing CO2 emissions from fossil fuel combustion. Hydrogen is a clean and efficient energy carrier and a hydrogen-based economy is now widely regarded as a potential solution for the future of energy security...
Cellulose-Based Carbon Molecular Sieve Membranes for Gas Separation: A Review
Araújo, T.; Gabriel Bernardo; Adélio MendesIn the field of gas separation and purification, membrane technologies compete with conventional purification processes on the basis of technical, economic and environmental factors. In this context, there is a growing interest in the development of carbon molecular sieve membranes (CMSM) due to their higher permeability and selectivity and higher stability in corrosive and high temperature environments. Howeve...
Development of hermetic glass frit encapsulation for perovskite solar cells
Seyedali Emami; Jorge Martins; Ruben Madureira; Daniel Hernandez; Gabriel Bernardo; Joaquim Mendes; Adélio MendesA hermetic laser-assisted glass frit encapsulation, at a process temperature of 120 degrees C, was developed for perovskite solar cell application. The hermeticity and long-term stability of the sealing was examined based on standard tests for photovoltaic (PV) applications. Encapsulations using fluorine doped tin oxide (FTO)-coated glass substrates displayed 8.93 x 10(-8) atm center dot cm(3) center dot s(-1) ...
Recent Developments in the Optimization of the Bulk Heterojunction Morphology o...
Adélio Mendes; Gabriel Bernardo; Hugo Gaspar; Flávio Figueira; Luiz Pereira; Júlio C. VianaOrganic photovoltaic (OPV) devices, made with semiconducting polymers, have recently attained a power conversion efficiency (PCE) over 14% in single junction cells and over 17% in tandem cells. These high performances, together with the suitability of the technology to inexpensive large-scale manufacture, over lightweight and flexible plastic substrates using roll-to-roll (R2R) processing, place the technology ...