Highly efficient electrocatalytic hydrogen evolution from neutral aqueous solution by a water-soluble anionic cobalt(ii) porphyrin

2015 ◽  
Vol 51 (81) ◽  
pp. 15067-15070 ◽  
Author(s):  
Belete B. Beyene ◽  
Sandeep B. Mane ◽  
Chen-Hsiung Hung
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Evolution ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Water Soluble ◽  
Applied Potential ◽  
Buffer Solution ◽  
Faradaic Efficiency ◽  
Highly Efficient ◽  
Neutral Aqueous Solution

CoTPPS is an efficient electrocatalyst for H2 generation from neutral phosphate buffer solution. It features quantitative Faradaic efficiency with a TOF of ∼1.83 s−1 and a TON of 1.9 × 104 mol of H2 per mole of catalyst at an applied potential of −1.29 V (vs. SHE).

scholarly journals Tunneling in the Hydrogen-Transfer Reaction from a Vitamin E Analog to an Inclusion Complex of 2,2-Diphenyl-1-picrylhydrazyl Radical with β-Cyclodextrin in an Aqueous Buffer Solution at Ambient Temperature

Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1966
Author(s):  
Ikuo Nakanishi ◽  
Yoshimi Shoji ◽  
Kei Ohkubo ◽  
Shunichi Fukuzumi
Keyword(s):  
Vitamin E ◽  
Phosphate Buffer ◽  
Hydrogen Transfer ◽  
Transfer Reaction ◽  
Phosphate Buffer Solution ◽  
Water Soluble ◽  
Quantum Mechanical ◽  
Buffer Solution ◽  
Quantum Mechanical Tunneling ◽  
Hydrogen Transfer Reaction

Recently, increasing attention has been paid to quantum mechanical behavior in biology. In this study, we investigated the involvement of quantum mechanical tunneling in the hydrogen-transfer reaction from Trolox, a water-soluble analog of vitamin E (α-tocopherol), to 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) in a phosphate buffer solution (0.05 M, pH 7.0). DPPH• was used as a reactivity model of reactive oxygen species and solubilized in water using β-cyclodextrin (β-CD). The second-order rate constants, kH and kD, in 0.05 M phosphate buffer solutions prepared with H2O (pH 7.0) and D2O (pD 7.0), respectively, were determined for the reaction between Trolox and DPPH•, using a stopped-flow technique at various temperatures (283–303 K). Large kinetic isotope effects (KIE, kH/kD) were observed for the hydrogen-transfer reaction from Trolox to the β-CD-solubilized DPPH• in the whole temperature range. The isotopic ratio of the Arrhenius prefactor (AH/AD = 0.003), as well as the isotopic difference in the activation energies (19 kJ mol−1), indicated that quantum mechanical tunneling plays a role in the reaction.

Ibuprofen removal from aqueous solution by in situ electrochemically generated ferrate(VI): proof-of-principle

2015 ◽  
Vol 73 (2) ◽  
pp. 389-395 ◽  
Author(s):  
Ljiljana Nikolić-Bujanović ◽  
Milan Čekerevac ◽  
Milena Tomić ◽  
Mladen Zdravković
Keyword(s):  
Aqueous Solution ◽  
Organic Carbon ◽  
Aqueous Solutions ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Oxygen Demand ◽  
Buffer Solution ◽  
Effective Removal ◽  
Proof Of Principle

The possibility of removing pharmaceuticals from aqueous solutions was examined using ibuprofen (Ibu) oxidation as an example, using in situ electrochemically synthesized ferrate(VI), a strong oxidant and coagulant, with forming of non-harmful byproducts. A solution of ibuprofen of 206 mg/L in 0.1 M phosphate buffer solution was treated with different amounts of fresh, electrochemically synthesized ferrate(VI). The changes of ibuprofen concentration in samples were determined using a UV-Vis spectrophotometer. The extent of mineralization was estimated using the changes in chemical oxygen demand (COD) values and total organic carbon (TOC) values of test samples. The largest reduction of the concentration of Ibu (41.75%) was obtained by adding 69.2 mg/L ferrate(VI) as Fe (Ibu: Fe = 1: 0.34). An effective removal of ibuprofen from aqueous solutions was recorded up to 68% and it can be done by using ferrate(VI) in the ratio Ibu: Fe = 1:3 as Fe. The possibility of ibuprofen removal by ferrate(VI) was confirmed by COD and TOC results, which demonstrated reduction up to 65% and 63.6%, respectively.

Photocatalytic hydrogen evolution from neutral aqueous solution by a water-soluble cobalt(ii) porphyrin

2018 ◽  
Vol 2 (9) ◽  
pp. 2036-2043 ◽  
Author(s):  
Belete B. Beyene ◽  
Chen-Hsiung Hung
Keyword(s):  
Aqueous Solution ◽  
Solar Energy ◽  
Hydrogen Evolution ◽  
Energy Demand ◽  
Water Soluble ◽  
Global Energy ◽  
Photocatalytic Hydrogen Evolution ◽  
Promising Strategy ◽  
Efficient Storage ◽  
Neutral Aqueous Solution

Efficient storage of solar energy via light-driven hydrogen evolution is an attractive and promising strategy to address challenges related to increasing global energy demand.

A water-soluble glucose-functionalized cobalt(iii) complex as an efficient electrocatalyst for hydrogen evolution under neutral conditions

2015 ◽  
Vol 44 (4) ◽  
pp. 1526-1529 ◽  
Author(s):  
Xuguang Yin ◽  
Cuibo Liu ◽  
Sifei Zhuo ◽  
You Xu ◽  
Bin Zhang
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Production ◽  
Hydrogen Evolution ◽  
Water Soluble ◽  
Neutral Aqueous Solution ◽  
Neutral Conditions

A water-soluble glucose functionalized cobalt(iii) complex [CoIII(dmgH)2(py-glucose)Cl] is active and stable for electrocatalytic hydrogen production in neutral aqueous solution.

scholarly journals Efficient solar hydrogen production from neutral electrolytes using surface-modified Cu(In,Ga)Se2photocathodes

2015 ◽  
Vol 3 (16) ◽  
pp. 8300-8307 ◽  
Author(s):  
Hiromu Kumagai ◽  
Tsutomu Minegishi ◽  
Naotoshi Sato ◽  
Taro Yamada ◽  
Jun Kubota ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Hydrogen Evolution ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Buffer Solution ◽  
Solar Hydrogen ◽  
Thin Conductor ◽  
Solar Hydrogen Production ◽  
Surface Modified

Surface thin conductor layers enhance sunlight driven hydrogen evolution from water using Cu(In,Ga)Se2photocathodes in a concentrated phosphate buffer solution.

scholarly journals Platinum(ii)–porphyrin as a sensitizer for visible-light driven water oxidation in neutral phosphate buffer

2015 ◽  
Vol 8 (3) ◽  
pp. 975-982 ◽  
Author(s):  
Hung-Cheng Chen ◽  
Dennis G. H. Hetterscheid ◽  
René M. Williams ◽  
Jarl Ivar van der Vlugt ◽  
Joost N. H. Reek ◽  
...  
Keyword(s):  
Visible Light ◽  
Water Oxidation ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
High Potential ◽  
Water Soluble ◽  
Buffer Solution ◽  
Visible Light Driven

A water-soluble Pt(ii)–porphyrin with a high potential for one-electron oxidation (∼1.42 V vs. NHE) proves very suitable for visible-light driven water oxidation in neutral phosphate buffer solution in combination with a variety of WOCs.

Bioceramic Hydroxyapatite Granules for Purification of Biotechnological Products

2011 ◽  
Vol 284-286 ◽  
pp. 1764-1769 ◽  
Author(s):  
Vitalijs Lakevics ◽  
Janis Locs ◽  
Dagnija Loca ◽  
Valentina Stepanova ◽  
Liga Berzina-Cimdina ◽  
...  
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Phosphate Buffer ◽  
Bovine Serum ◽  
Phosphate Buffer Solution ◽  
Sorption Process ◽  
Buffer Solution ◽  
Ph Values ◽  
Bovine Serum Albumin Adsorption ◽  
Albumin Adsorption

Sorption experiments of bovine serum albumin (BSA) on hydroxyapatite (HAp) ceramic granules, prepared at three temperatures 900°C, 1000°C and 1150°C were performed at room temperature 18,6 °C and phosphate buffer, pH 5,83; 6.38 and 7,39. Thermal treatment contributed to the decrease of bovine serum albumin immobilization indicating that sorption process depended on HAp ceramics specific surface area and pH values of phosphate buffer solution. However, it was confirmed that granule size was also an important parameter for bovine serum albumin adsorption. As a result of these experiments, the most appropriate adsorption conditions and phosphate buffer pH values influence on to BSA sorption were analyzed.

Reduction of Escherichia coli O157:H7 Counts on Whole Fresh Apples by Treatment with Sanitizers

2000 ◽  
Vol 63 (6) ◽  
pp. 703-708 ◽  
Author(s):  
MARCY A. WISNIEWSKY ◽  
BONITA A. GLATZ ◽  
MARK L. GLEASON ◽  
CHERYLL A. REITMEIER
Keyword(s):  
Escherichia Coli ◽  
Chlorine Dioxide ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Escherichia Coli O157 ◽  
Peroxyacetic Acid ◽  
Water Control ◽  
Buffer Solution ◽  
E Coli ◽  
Log Reduction

The objectives of this study were to determine if washing of whole apples with solutions of three different sanitizers (peroxyacetic acid, chlorine dioxide, or a chlorine-phosphate buffer solution) could reduce a contaminating nonpathogenic Escherichia coli O157:H7 population by 5 logs and at what sanitizer concentration and wash time such a reduction could be achieved. Sanitizers were tested at 1, 2, 4, 8, and 16 times the manufacturer's recommended concentration at wash times of 5, 10, and 15 min. Whole, sound Braeburn apples were inoculated with approximately 1 × 108 or 7 × 106 CFU per apple, stored for 24 h, then washed with sterile water (control) or with sanitizers for the prescribed time. Recovered bacteria were enumerated on trypticase soy agar. Washing with water alone reduced the recoverable population by almost 2 logs from the starting population; this can be attributed to physical removal of organisms from the apple surface. No sanitizer, when used at the recommended concentration, reduced the recovered E. coli population by 5 logs under the test conditions. The most effective sanitizer, peroxyacetic acid, achieved a 5-log reduction when used at 2.1 to 14 times its recommended concentration, depending on the length of the wash time. The chlorine-phosphate buffer solution reduced the population by 5 logs when used at 3 to 15 times its recommended concentration, depending on wash time. At no concentration or wash time tested did chlorine dioxide achieve the 5-log reduction.

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