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To evaluate the photoelectrochemical performances of TNTs for seawater splitting, linear sweep voltammetry (LSV) measurements were carried out in seawater (pH ~8) electrolyte under simulated solar light illumination (AM 1.5G, 100 mW cm-2). As shown in Figure 46 (a), the LSV curve exhibited no observable dark current even up to a high potential of 1.6 VRHE, and a significant photocurrent density as high as ~1.42 mA/cm2 at 1.23 VRHE was observed under light illumination as well as low onset potential of 0.2 VRHE. The photoconversion efficiency (ηAPE) of the TNTs photoanode was calculated. Figure 43 shows the change of photoconversion efficiency as a function of applied bias potential (VRHE). The maximum value of ηAPE reached 0.5% at 0.68 VRHE, which is comparable to the reported value for pristine TiO2 nanostructures.134 The transient photocurrent response of TNTs was measured at 0.7 VRHE with on and off cycles of light illumination (Figure 46 (b)). When the light was switched on, the photocurrent increased suddenly to a transient maximum, and then, it gradually decayed to a relatively steady-state. The current returned to nearly zero immediately once the illumination was switched off. Such photocurrent responses were fast and reproducible during repeated light on/off cycles, thus demonstrating the stability and reproducibility of a TNTs under successive cycles. On the other hand, we observed photocurrent decay in transients, which could have been attributed to the redistribution of the interfacial potential through the charge carrier accumulation at the electrode–electrolyte interface or trapping of electrons or holes in intermediate surface states. For further understanding of the photocharge carrier transport and recombination properties, the open-circuit potential response was measured under light on and off cycles, which were accompanied by photovoltage relaxation from a quasi-equilibrium state (i.e., pseudo Fermi level for photogenerated holes) under illumination to the equilibrium (Fermi level of TNTs for electrons) at darkness. In other words, as shown in Figure 44 (a), when switching the light on from a steady-state in the dark, the TNTs exhibited a negative shift of photovoltage due to photogenerated electron accumulation, thus resulting in rapid shifts of the Fermi level to cathodic potentials. Meanwhile, when switching the light off, subsequently, gradual photovoltage decay was observed until the Fermi level returned to an original level due to the charge recombination. The corresponding response time clearly increased with photovoltage decay, thus indicating a long electron lifetime (Figure 44 (b)). In addition, we measured the electrochemical impedance spectroscopy (EIS) at 0.7 VRHE with an AC frequency range from 0.01 Hz to 700 kHz under simulated sunlight. Figure 45 presents the comparison of Nyquist (Figure 45 (a)) and Bode plots (Figure 45 (b)) of EIS data in different 1 M KOH (pH = ~14) and seawater (pH = ~8) electrolytes. Interestingly, we observed one single semicircle and one broad peak in the Nyquist and Bode phase at the low frequency range irrespective of electrolytes, thus demonstrating evidence of a single lifetime or relaxation time of charge carriers. The electron lifetime (τe) in the TNTs can be obtained from the characteristic angular frequency (ω) of the middle frequency (f) peak in the Bode phase plots by using the relation of τe = 1/ ω = 1/2 πf. The characteristic frequency for the TNTs was 1.21 Hz and 2.17 Hz, 71PDF Image | China solar seawater battery
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ORC Waste Heat Turbine and ORC System Build Plans: All turbine plans are $10,000 each. This allows you to build a system and then consider licensing for production after you have completed and tested a unit.Redox Flow Battery Technology: With the advent of the new USA tax credits for producing and selling batteries ($35/kW) we are focussing on a simple flow battery using shipping containers as the modular electrolyte storage units with tax credits up to $140,000 per system. Our main focus is on the salt battery. This battery can be used for both thermal and electrical storage applications. We call it the Cogeneration Battery or Cogen Battery. One project is converting salt (brine) based water conditioners to simultaneously produce power. In addition, there are many opportunities to extract Lithium from brine (salt lakes, groundwater, and producer water).Salt water or brine are huge sources for lithium. Most of the worlds lithium is acquired from a brine source. It's even in seawater in a low concentration. Brine is also a byproduct of huge powerplants, which can now use that as an electrolyte and a huge flow battery (which allows storage at the source).We welcome any business and equipment inquiries, as well as licensing our turbines for manufacturing.CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)