scholarly journals Toward enhanced hydrogen generation from water using oxygen permeating LCF membranes

2015 ◽  
Vol 17 (15) ◽  
pp. 10093-10107 ◽  
Author(s):  
Xiao-Yu Wu ◽  
Le Chang ◽  
Mruthunjaya Uddi ◽  
Patrick Kirchen ◽  
Ahmed F. Ghoniem

Oxygen permeating La0.9Ca0.1FeO3−δ membranes significantly enhance hydrogen production rate from water thermolysis, especially when coupled with fuel oxidation.

RSC Advances ◽  
2017 ◽  
Vol 7 (28) ◽  
pp. 17551-17558 ◽  
Author(s):  
Lan Sun ◽  
Zhi Wu ◽  
Siwan Xiang ◽  
Jiangdong Yu ◽  
Yingying Wang ◽  
...  

A photoelectrocatalytic hydrogen production rate of 37.8 μmol h−1 cm−2 was obtained by a newly designed NiO nanoparticle modified TiO2 nanotube array photoanode.


2010 ◽  
Vol 61 (9) ◽  
pp. 2303-2308 ◽  
Author(s):  
X. Wang ◽  
K. Shih ◽  
X. Y. Li

A microemulsion technique was employed to synthesize nano-sized photocatalysts with a core (CdS)/shell (ZnS) structure. The primary particles of the photocatalysts were around 10 nm, and the mean size of the catalyst clusters in water was about 100 nm. The band gaps of the catalysts ranged from 2.25 to 2.46 eV. The experiments of photocatalytic H2 generation showed that the catalysts (CdS)x/(ZnS)1−x with x ranging from 0.1 to 1 were able to produce hydrogen from water photolysis under visible light. The catalyst with x = 0.9 had the highest rate of hydrogen production. The catalyst loading density also influenced the photo-hydrogen production rate, and the best catalyst concentration in water was 1 g L−1. The stability of the nano-catalysts in terms of size, morphology and activity was satisfactory during an extended test period for a specific hydrogen production rate of 2.38 mmol g−1 L−1 h−1 and a quantum yield of 16.1% under visible light (165 W Xe lamp, λ > 420 nm). The results demonstrate that the (CdS)/(ZnS) core/shell nano-particles are a novel photo-catalyst for renewable hydrogen generation from water under visible light. This is attributable to the large band-gap ZnS shell that separates the electron/hole pairs generated by the CdS core and hence reduces their recombinations.


2021 ◽  
Vol 71 (1) ◽  
Author(s):  
Jiang-Yu Ye ◽  
Yue Pan ◽  
Yong Wang ◽  
Yi-Chao Wang

Abstract Purpose This study utilized the principle that the bacteriorhodopsin (BR) produced by Halobacterium salinarum could increase the hydrogen production of Rhodobacter sphaeroides. H. salinarum are co-cultured with R. sphaeroides to determine the impact of purple membrane fragments (PM) on R. sphaeroides and improve its hydrogen production capacity. Methods In this study, low-salinity in 14 % NaCl domesticates H salinarum. Then, 0–160 nmol of different concentration gradient groups of bacteriorhodopsin (BR) and R. sphaeroides was co-cultivated, and the hydrogen production and pH are measured; then, R. sphaeroides and immobilized BR of different concentrations are used to produce hydrogen to detect the amount of hydrogen. Two-chamber microbial hydrogen production system with proton exchange membrane-assisted proton flow was established, and the system was operated. As additional electricity added under 0.3 V, the hydrogen production rate increased with voltages in the coupled system. Results H salinarum can still grow well after low salt in 14% NaCl domestication. When the BR concentration is 80 nmol, the highest hydrogen production reached 217 mL per hour. Both immobilized PC (packed cells) and immobilized PM (purple membrane) of H. salinarum could promote hydrogen production of R. sphaeroides to some extent. The highest production of hydrogen was obtained by the coupled system with 40 nmol BR of immobilized PC, which increased from 127 to 232 mL, and the maximum H2 production rate was 18.2 mL−1 h−1 L culture. In the 192 h experiment time, when the potential is 0.3 V, the hydrogen production amount can reach 920 mL, which is 50.3% higher than the control group. Conclusions The stability of the system greatly improved after PC was immobilized, and the time for hydrogen production of R. sphaeroides significantly extended on same condition. As additional electricity added under 0.3 V, the hydrogen production rate increased with voltages in the coupled system. These results are helpful to build a hydrogen production-coupled system by nitrogenase of R. sphaeroides and proton pump of H. salinarum. Graphical abstract


2015 ◽  
Vol 98 ◽  
pp. 383-389 ◽  
Author(s):  
Chiung-Yi Cheng ◽  
Kuang-Li Cheng ◽  
Terng-Jou Wan ◽  
Wei-Nung Kuo ◽  
Feng-Jen Chu ◽  
...  

Nanoscale ◽  
2017 ◽  
Vol 9 (43) ◽  
pp. 17029-17036 ◽  
Author(s):  
Arka Saha ◽  
Apurba Sinhamahapatra ◽  
Tong-Hyun Kang ◽  
Subhash C. Ghosh ◽  
Jong-Sung Yu ◽  
...  

An efficient ‘noble metal free’ hydrogenated MoS2 QD-TiO2 heterojunction photocatalyst with a superior hydrogen production rate of 3.1 mmol g−1 h−1 is reported.


2014 ◽  
Vol 50 (14) ◽  
pp. 1731-1734 ◽  
Author(s):  
Zheng Wang ◽  
Jungang Hou ◽  
Chao Yang ◽  
Shuqiang Jiao ◽  
Hongmin Zhu

Three-dimensional MoS2–CdS–γ-TaON hollow nanostructures as novel photocatalysts were firstly synthesized via a facile hydrothermal method and they exhibit a high photocatalytic hydrogen production rate without a noble metal.


Author(s):  
Alicia Keow ◽  
Zheng Chen

Abstract Proton exchange membrane (PEM) electrolyzers with the ability to produce gases at a pressure suitable for direct metal hydride storage are desirable because they do not require the use of compressors and other auxiliary components. Direct storage into metal hydride cylinders is made feasible when the pressure and flow rate of hydrogen is controlled. The nonlinear dynamics of the PEM electrolyzer change with temperature and pressure, both of which change with the hydrogen production rate, and are thus difficult to estimate. Therefore, a model-free, relay-feedback, auto-tuning approach is used to tune a proportional integral (PI) controller. This allows for the determination of the voltage supply to the electrolyzer by tracking the current set-point and correlating it to the hydrogen production rate. A gain scheduling approach is used to record the tuned controller’s parameters at different set-points, minimizing the frequency of tuning the device. A self-assessment test is used to determine situations where the auto-tuner should activate to update the PI parameters, thus, allowing for the system to operate without supervision. The auto-tuning PI control is successfully tested with a PEM electrolyzer setup. Experimental results showed that an auto-tuner can tune the controller parameters and produce favorable transient behaviors, allowing for a degree of adaptability for variations in system set-points.


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