1. Tungsten carbide electrocatalysts prepared from metallic tungsten nanoparticles for efficient hydrogen evolutionPlamen Stefanov, Abdullah Yildiz, Hasan Okuyucu, Saim Emin, Cesur Altinkaya, Ali Semerci, 2018, izvirni znanstveni članek Najdeno v: ključnih besedah Ključne besede: Tungsten carbide, Colloid, Hydrogen evolution, Overpotential, Electrocatalyst Objavljeno: 23.05.2018; Ogledov: 3875; Prenosov: 0
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2. Solvothermal synthesis of iron phosphides and their application for efficient electrocatalytic hydrogen evolutionSaim Emin, Takwa Chouki, Manel Machreki, 2020, izvirni znanstveni članek Opis: Abstract
In this paper, we present a solvothermal synthesis of iron phosphide electrocatalysts using a triphenylphosphine (TPP) precursor. The synthetic protocol generates Fe2P phase at 300 °C and FeP phase at 350 °C. To enhance the catalytic activities of obtained iron phosphide particles heat-treatments were carried out at elevated temperatures. Annealing at 500 °C under reductive atmosphere induced structural changes in the samples: (i) Fe2P provided a pure Fe3P phase (Fe3P−500 °C) and (ii) FeP transformed into a mixture of iron phosphide phases (Fe2P/FeP−500 °C). Pure Fe2P films was prepared under argon atmosphere at 450 °C (Fe2P−450 °C). The electrocatalytic activities of heat-treated Fe2P−450 °C, Fe3P−500 °C, and Fe2P/FeP−500 °C catalysts were studied for hydrogen evolution reaction (HER) in 0.5 M H2SO4. The HER activities of the iron phosphide catalyst were found to be phase dependent. The lowest electrode potential of 110 mV vs. a reversible hydrogen electrode (RHE) at 10 mA cm−2 was achieved with Fe2P/FeP−500 °C catalyst. Najdeno v: ključnih besedah Povzetek najdenega: ...Solvothermal synthesis, Iron phosphide, Electrocatalyst, Hydrogen evolution, Overpotential... Ključne besede: Solvothermal synthesis, Iron phosphide, Electrocatalyst, Hydrogen evolution, Overpotential Objavljeno: 20.07.2020; Ogledov: 1850; Prenosov: 0
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3. Growth of MoSe2 electrocatalyst from metallic molybdenum nanoparticles for efficient hydrogen evolutionSaim Emin, Plamen Stefanov, Burhancan Aktarla, Takwa Chouki, Boriana Donkova, 2021, izvirni znanstveni članek Opis: Molybdenum diselenide (MoSe2) is an emerging alternative to platinum-group-metal electrocatalysts for the
hydrogen evolution reaction (HER). Herein, the chemical vapor deposition (CVD) approach was demonstrated to
be a successful route to grow MoSe2 thin films using colloidal molybdenum nanoparticles (Mo NPs). T Najdeno v: ključnih besedah Ključne besede: Water splitting, electrocatalyst, MoSe2 Objavljeno: 15.01.2021; Ogledov: 1615; Prenosov: 0
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4. Synthesis of efficient iron phosphide catalyst for electrocatalytic hydrogen generationTakwa Chouki, D. Lazarević, B. Donkova, Saim Emin, 2021, izvirni znanstveni članek Opis: A solvothermal synthesis of iron phosphide electrocatalysts using triphenylphosphine (TPP) as phosphorus precursor
is presented. The synthetic protocol generates Fe2P/FeP phase at 350°C. After deposition of the catalyst onto graphite
substrate heat-treatment at higher temperature was carried out. Annealing at 500°C under reductive atmosphere induced
structural changes in the Fe2P/FeP samples which yielded a pure Fe2P phase. The electrocatalytic activity of the Fe2P
catalyst was studied for hydrogen evolution reaction (HER) in 0.5 M H2SO4. The recorded overpotential for HER was
about 130 mV vs. a reversible hydrogen electrode (RHE) at 10 mA cm−2 Najdeno v: ključnih besedah Povzetek najdenega: ...solvothermal synthesis, iron phosphide, electrocatalyst, hydrogen evolution... Ključne besede: solvothermal synthesis, iron phosphide, electrocatalyst, hydrogen evolution Objavljeno: 10.05.2021; Ogledov: 1368; Prenosov: 0
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5. Solvothermal synthesis of iron phosphides and their application for efficient electrocatalytic hydrogen evolutionSaim Emin, Manel Machreki, Takwa Chouki, 2020, objavljeni povzetek znanstvenega prispevka na konferenci Opis: We report the solvothermal synthesis of iron phosphide electrocatalysts using a low-cost phosphorus precursor [1]. The synthetic protocol allows for the preparation of a Fe2P phase at 300°C and FeP phase at 350°C. To enhance the catalytic activities of obtained iron phosphide particles, heat-treatments were carried out at elevated temperatures. Annealing at 500°C induced structural changes in the samples: (i) Fe2P provided a pure Fe3P phase (Fe3P−500°C) and (ii) FeP transformed into a mixture of iron phosphide phases (Fe2P/FeP−500°C). The electrocatalytic activities of heat-treated Fe2P−450°C, Fe3P−500°C, and Fe2P/FeP−500°C catalysts were studied for hydrogen evolution reaction (HER) in 0.5 M sulfuric acid (H2SO4). The HER activities of the iron phosphide catalyst were found to be phase dependent. The lowest recorded overpotential of 110 mV at 10 mA cm−2 vs. a reversible hydrogen electrode was achieved with Fe2P/FeP−500°C catalyst. The present approach allows the preparation of immobilized iron phsphide catalyst onto carbon support which is essential for application purpose. The procedure developed by us is an elegant approach to tune the composition of iron phosphide catalyst and control the morphology of particles. Najdeno v: ključnih besedah Povzetek najdenega: ...solvothermal synthesis, iron phosphide, electrocatalyst, hydrogen evolution, overpotential... Ključne besede: solvothermal synthesis, iron phosphide, electrocatalyst, hydrogen evolution, overpotential Objavljeno: 13.05.2021; Ogledov: 1371; Prenosov: 0
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6. Iron phosphides as efficient electrocatalyst for hydrogen evolution and energy conversionTakwa Chouki, Saim Emin, 2021, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Transition metal phosphides have been demonstrated as outstanding multifunctional catalysts in a broad range of energy conversion technologies. We developed a solvothermal synthesis approach for iron phosphide electrocatalystsusing a low-cost phosphorus precursor.The synthetic protocol allows for the preparation of a Fe2P phase at 300°C and FeP phase at 350°C. The obtained compounds were coated on conductive substrates to prepare catalysts thin films. Here, we exploited different phases of iron phosphide as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs) with an I−/I3− based electrolyte [2]. The solar-to-current conversion efficiency of the solar cells assembled with the Fe2P material reached 3.96±0.06%,which is comparable to the device assembled with a platinum (Pt) CE. In addition to DSSC
applications, the iron phosphides were used as electrocatalyst for H2 evolution (Fig. 1). To enhance the catalytic activities of obtained iron phosphide particles, heat-treatments were carried out at elevated temperatures.Annealing at 500°C induced structural changes in the samples: (i) Fe2P provided a pure Fe3P phase (Fe3P−500°C) and (ii) FeP transformed into a mixture of iron phosphide phases (Fe2P/FeP−500°C). The electrocatalytic activities for H2 evolution of heat-treated catalysts were studied in 0.5 M sulfuric acid (H2SO4). The HER activities of the iron phosphide catalyst were found to be phase dependent. The lowest recorded overpotential of 110 mV at 10 mA cm−2 vs. a reversible hydrogen electrode was achieved with Fe2P/FeP−500°C catalyst. The developed procedure is an elegant approach to tune the composition of iron phosphide catalyst and control the morphology of particles. Najdeno v: ključnih besedah Ključne besede: Iron phosphides
electrocatalyst
hydrogen evolution
energy conversion Objavljeno: 06.02.2023; Ogledov: 276; Prenosov: 0
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