Research

CO₂ conversions

 
Electrochemical CO₂ and water electrolysis

The electrochemical conversion of CO₂ to high energy density fuels and valuable chemicals is generally considered a sustainable method for reducing CO₂ emissions and storing intermittent renewable electricity. The overall CO₂ electrolysis process is typically divided into two half-cell redox reaction: CO₂ reduction reaction (CO₂RR) and oxygen evolution reaction (OER). Therefore, our lab studies have been focused on developing efficient electrocatalysts for OER and CO₂RR.

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✔Noble Metal based Electrocatalysts for OER

There is a growing interest in clean energy because of problems such as environmental pollution in the current energy supply and demand system based on fossil fuels. Particularly, researches for using as a clean energy source using electrochemical water splitting are being actively carried out. Among them, inhibitor of the efficiency of water splitting reaction is a large overpotential on the anode and is the catalyst instability in the oxidation condition. Our research group is evaluating the performance by synthesizing Noble metal-based catalysts to ensure excellent performance and stability. Furthermore, various research equipment are being used to investigate the relationship between various oxidation states and activity catalyst.

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✔Non-noble Metal based Electrocatalysts for OER

Both computational and experimental studies have recently shown that the noble metal-based oxides such as Ir and Ru are most active electrocatalysts for OER. However, high cost and scarcity of these noble metal-based materials hinder their large-scale application. To overcome this problem, Our lab focused to develop non-noble metal-based electrode for OER. Our simple and scalable method appear to be promising method to ensure economic feasibility

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✔Non-noble Metal based Electrocatalysts for CO₂RR

The electrochemical reduction of CO₂ using renewable electricity is an important future CO₂-to fuels/chemicals process, which converts the greenhouse gas CO₂ directly into useful chemicals, polymer precursors, and fuels, such as carbon monoxide (CO), acetaldehyde, ethylene, and ethanol. However, the CO₂RR faces formidable obstacles with respect to commercialization due to its low efficiency and poor selectivity. Our research has been dedicated to identifying efficient and selective catalysts for CO₂RR. Our studies highlight the need for a concomitant consideration of factors related to intrinsic catalytic activity of the active phase, its porous structure and its hydrophilicity/phobicity to achieve a sustained high product yield

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Electrochemical Devices

An electrochemical device is a cell capable of either generating electrical energy from chemical reactions or using electrical energy to cause chemical reactions. The electrochemical device which generate an electric current are called voltaic cells or galvanic cells and those that generate chemical reactions, via electrolysis for example, are called electrolytic cells.

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✔Electrolyzer for Water Splitting

Electrolysis of water is the decomposition of water into oxygen and hydrogen gas due to the passage of an electric current. The reaction has a standard potential of −1.23 V, meaning it ideally requires a potential difference of 1.23 volts to split water.  In our lab, electrode and cell design was investigated for high performance water splitting.

✔CO2 electrolyzer

The electrochemical reduction of carbon dioxide is the conversion of carbon dioxide(CO₂RR) to more reduced chemical species using electrical energy. The first examples of electrochemical reduction of carbon dioxide are from the 19th century, when carbon dioxide was reduced to carbon monoxide using a zinc cathode.

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✔Stack System for CO₂ Reduction Reaction (CO₂RR)

Electrochemical reduction of carbon dioxide represents a possible means of producing chemicals or fuels, converting carbon dioxide (CO₂) to organic feedstocks such as formic acid (HCOOH), methanol (CH3OH), ethylene (C2H4), methane (CH4), and carbon monoxide (CO).  In our lab, electrode and cell design was researched to produce large amount of valuable chemicals.

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✔Photo Electrochemical Devices

Solar to fuel is a synthetic chemical fuel produced directly/indirectly from solar energy sunlight/solar heat through photochemical/photobiological, thermochemical (i.e., through the use of solar heat supplied by concentrated solar thermal energy to drive a chemical reaction), and electrochemical reaction. Light is used as an energy source, with solar energy being transduced to chemical energy, typically by reducing protons to hydrogen, or carbon dioxide to organic compounds. In our lab, electrode and cell design was investigated for increasing solar to fuel efficiency.

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Electrochemical Flow Cell for in-situ/Operando Analysis

In-situ/Operando analysis is an analytical methodology wherein the spectroscopic characterization of materials undergoing reaction is coupled simultaneously with measurement of catalytic activity and selectivity. The primary concern of this methodology is to establish structure-reactivity/selectivity relationships of catalysts and thereby yield information about mechanisms. Other uses include those in engineering improvements to existing catalytic materials and processes and in developing new ones. In situ/operando analysis requires measurement of the catalyst under (ideally) real working conditions, involving comparable temperature and pressure environments to those of industrially catalyzed reactions. In our lab, various In situ/operando analysis was prepared for mechanism and characterize study using techniques such as XRD, ICP, XAFS, and Raman.

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