Browsing by Author "Gliniak, Jacek"

Now showing 1 - 6 of 6

A Ruthenium-Based Biomimetic Hydrogen Cluster for Efficient Photocatalytic Hydrogen Generation from Formic Acid
(2015-04-20)
Chang, Chin-Hao
;
Chen, Mei-Hua
;
Du, Wan-Shan
;
Gliniak, Jacek
;
Lin, Jia-Hoa
A ruthenium-based biomimetic hydrogen cluster, [Ru-2(CO)(6)(-SCH2CH2CH2S)] (1), has been synthesized and, in the presence of the P ligand tri(o-tolyl)phosphine, demonstrated efficient photocatalytic hydrogen generation from formic acid decomposition. Turnover frequencies (TOFs) of 5500h(-1) and turnover numbers (TONs) over 24700 were obtained with less than 50ppm of the catalyst, thus representing the highest TOFs for ruthenium complexes as well as the best efficiency for photocatalytic hydrogen production from formic acid. Moreover, 1 showed high stability with no significant degradation of the photocatalyst observed after prolonged photoirradiation at 90 degrees C.
Biomimic nickel thiolate catalyst with CdS nanomaterial for photocatalytic hydrogen production in aqueous phase
(2016-07-25)
Gliniak, Jacek
;
交大名義發表
;
National Chiao Tung University
Biomimic nickel thiolate catalyst with CdS nanomaterial for photocatalytic hydrogen production in aqueous phase
(2016-07-25)
Gliniak, Jacek
;
交大名義發表
;
National Chiao Tung University
Enhanced hydrogen generation from formic acid by a biomimetic ruthenium complex with a covalently bonded phosphine ligand
(2017-04-13)
Chen, Mei-Hua
;
Lin, Jia-Hoa
;
Li, Chuen-Ru
;
Gliniak, Jacek
;
Chang, Chin-Hao
A series of [Ru-2(CO)(5)(mu-SCH2CH2CH2S)PXS] complexes (Ru-2-S-2-PXS, X = phosphine ligands, S = 1-8) have been synthesized and evaluated for their photocatalytic H-2 generation efficiencies from formic acid decomposition. The [Ru-2(CO)(5)(mu-SCH2CH2CH2S)P(o-C6H4CH3)(3)] (Ru-2-S-2-PX4) catalyst + P(CH3)(3) ligand exhibited a high turnover frequency of 15,840h(-1) and turnover number of 24,536. A mechanistic investigation of the Ru-2-S-2-PX4 + FA/TEA catalyzed photocatalytic H-2 generation reaction using ATR-IR, EI-MS, and NMR techniques suggested that when Ru2-S2-PX4 was photoirradiated, the P(o-C6H4CH3)(3) was dissociated from the complex to form a new species, [Ru-2(CO)(5)(mu-SCH2CH2CH2S)]* (I). The free P(o-C6H4CH3)(3) then attacks a second molecule of Ru-2-S-2-PX4 to form Ru-2-S-2-(PX4)(2) and release of free CO, which is then combined with species I to form Ru-2-S-2. Subsequent attachment of formate ion to species Ru-2-S-2-PX4, Ru-2-S-2, and Ru-2-S-2-(PX4)(2) to form [Ru-2(CO)(5)(mu-SCH(2)CH(2)CH(2)SA]-HC00(-) (II), Ru-2-S-2-HCOO- (II') and Ru-2-S-2-PX4-HCOO- (II"), respectively. Rearrangement of complex II (or II' or II") and evolution of CO2 generate a transient complex [Ru-2(CO)(5)(mu-SCH2CH2CH2S)H (III), which then undergoes a protonation process to yield complex [Ru-2(CO)(5)(mu-SCH2CH2CH2S)H-2] (IV). Release of H-2 and re-incorporation of the formate anion as well as evolution of CO2 regenerates the active complex III and the cycle begins again. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
High-Rate Hydrogen Generation by Direct Sunlight Irradiation with a Triruthenium Complex
(2019-02-04)
Wu, Tung-Kung
;
Chen, Yi-Ting
;
Peng, Chun-Sheng
;
Lin, Jia-Hoa
;
Gliniak, Jacek
Herein we report a biomimetic triruthenium catalyst that, when under direct sunlight irradiation, facilitates high-rate H-2 production from formic acid (FA) dehydrogenation. The system consists of 2 mu mol of catalyst and 6 mu mol of tri-o-tolylphosphine in 1 mL of dimethylformamide (DMF) and 4 mL of FA/triethylamine (TEA; 5:2). With 0.4 mM catalyst loaded, a high turnover frequency of 1.15 X 10(6) h(-1) was detected when under direct sunlight irradiation. In an experiment with 0.2 mM catalyst loaded, more than 140 L of H-2 (280 L of H-2 + CO2) was produced, and a turnover number of approximately 2.78 X 10(6) was obtained within 5 h without decline in H-2 generation activity, making it suitable for high-rate H-2 production.
Sulfur-Doped Graphene Oxide Quantum Dots as Photocatalysts for Hydrogen Generation in the Aqueous Phase
(2017-08-24)
Gliniak, Jacek
;
Lin, Jia-Hoa
;
Chen, Yi-Ting
;
Li, Chuen-Ru
;
Jokar, Efat
Sulfur-doped graphene oxide quantum dots (S-GOQDs) were synthesized and investigated for efficient photocatalytic hydrogen generation application. The UV/Vis, FTIR, and photoluminescence spectra of the synthesized S-GOQDs exhibit three absorption bands at 333, 395, and 524 nm, characteristic of C=S and C=S stretching vibration signals at 1075 and 690 cm(-1), and two excitation-wavelength-independent emission signals with maxima at 451 and 520 nm, respectively, confirming the successful doping of S atom into the GOQDs. Electronic structural analysis suggested that the S-GOQDs exhibit conduction band minimum (CBM) and valence band maximum (VBM) levels suitable for water splitting. Under direct sunlight irradiation, an initial rate of 18166 mu molh(-1) g(-1) in pure water and 30519 mu molh(-1) g(-1) in 80% ethanol aqueous solution were obtained. Therefore, metal-free and inexpensive S-GOQDs hold great potential in the development of sustainable and environmentally friendly photocatalysts for efficient hydrogen generation from water splitting.