The Experts below are selected from a list of 3612 Experts worldwide ranked by ideXlab platform
Yi Cui - One of the best experts on this subject based on the ideXlab platform.
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Symmetrical MnO2–Carbon Nanotube–Textile Nanostructures for Wearable Pseudocapacitors with High Mass Loading
ACS Nano, 2011Co-Authors: Xing Xie, Mauro Pasta, Husam N Alshareef, Yuan Yang, Nian Liu, Yan Yao, Yi CuiAbstract:While MnO2 is a promising material for pseudocapacitor applications due to its high specific capacity and low cost, MnO2 electrodes suffer from their low electrical and ionic conductivities. In this article, we report a structure where MnO2 nanoflowers were conformally electrodeposited onto carbon nanotube (CNT)-enabled Conductive Textile fibers. Such nanostructures effectively decrease the ion diffusion and charge transport resistance in the electrode. For a given areal mass loading, the thickness of MnO2 on Conductive Textile fibers is much smaller than that on a flat metal substrate. Such a porous structure also allows a large mass loading, up to 8.3 mg/cm2, which leads to a high areal capacitance of 2.8 F/cm2 at a scan rate of 0.05 mV/s. Full cells were demonstrated, where the MnO2–CNT–Textile was used as a positive electrode, reduced MnO2–CNT–Textile as a negative electrode, and 0.5 M Na2SO4 in water as the electrolyte. The resulting pseudocapacitor shows promising results as a low-cost energy storag...
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symmetrical mno2 carbon nanotube Textile nanostructures for wearable pseudocapacitors with high mass loading
ACS Nano, 2011Co-Authors: Xing Xie, Mauro Pasta, Husam N Alshareef, Yuan Yang, Nian Liu, Yan Yao, Yi CuiAbstract:While MnO2 is a promising material for pseudocapacitor applications due to its high specific capacity and low cost, MnO2 electrodes suffer from their low electrical and ionic conductivities. In this article, we report a structure where MnO2 nanoflowers were conformally electrodeposited onto carbon nanotube (CNT)-enabled Conductive Textile fibers. Such nanostructures effectively decrease the ion diffusion and charge transport resistance in the electrode. For a given areal mass loading, the thickness of MnO2 on Conductive Textile fibers is much smaller than that on a flat metal substrate. Such a porous structure also allows a large mass loading, up to 8.3 mg/cm2, which leads to a high areal capacitance of 2.8 F/cm2 at a scan rate of 0.05 mV/s. Full cells were demonstrated, where the MnO2–CNT–Textile was used as a positive electrode, reduced MnO2–CNT–Textile as a negative electrode, and 0.5 M Na2SO4 in water as the electrolyte. The resulting pseudocapacitor shows promising results as a low-cost energy storag...
V Groza - One of the best experts on this subject based on the ideXlab platform.
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impact of skin electrode interface on electrocardiogram measurements using Conductive Textile electrodes
IEEE Transactions on Instrumentation and Measurement, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V Groza, Izmail BatkinAbstract:Physicians' understanding of biosignals as measured with medical instruments becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments' recordings exactly reflect what is happening in the patient's body so that the acquired signal is the real one or at least as close to the real in-body signal as possible. This is such an important issue that sometimes physicians use invasive measurements to obtain the real biosignal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this paper, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. To evaluate the performance of the device, we use it to measure ECG and apply Conductive Textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results, allowing us to investigate if ECG measured with the device is proper for applications where no skin preparation is allowed, such as ECG-assisted blood pressure monitoring devices. Next, we propose a method to reconstruct the ECG signal from the signal acquired by our device, with respect to the interface characteristics and their relation to the ECG. The interface in this paper is skin–electrode interface for Conductive Textiles. In the last stage of this paper, we explore the effects of pressure on skin–electrode interface impedance and its parametrical variation.
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measuring skin electrode impedance variation of Conductive Textile electrodes under pressure
The Journal of Thoracic and Cardiovascular Surgery, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V GrozaAbstract:Electrocardiogram (ECG) is the first bio-signal physicians use to diagnose cardiovascular diseases, since any kind of heart abnormality reflects on it. ECG electrodes play an important role in collecting this signal. One type of ECG electrodes which is recently getting more popular, especially due to its user friendly features compared to traditional Ag/AgCl electrodes, is Conductive Textile. Similar to any other type of electrode, Conductive Textile is associated with skin-electrode interface impedance located between the body (source of signal) and ECG monitoring device, thus affecting the recorded ECG quality. In this paper, we measure the skin-electrode impedance of Conductive Textile electrodes under various pressure levels, because in some applications ECG electrode is located under a blood pressure cuff and therefore it is under pressure when the cuff is inflated. We show that in fact under pressure the impedance decreases, resulting in a higher quality ECG measurement.
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I2MTC - Measuring skin-electrode impedance variation of Conductive Textile electrodes under pressure
2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V GrozaAbstract:Electrocardiogram (ECG) is the first bio-signal physicians use to diagnose cardiovascular diseases, since any kind of heart abnormality reflects on it. ECG electrodes play an important role in collecting this signal. One type of ECG electrodes which is recently getting more popular, especially due to its user friendly features compared to traditional Ag/AgCl electrodes, is Conductive Textile. Similar to any other type of electrode, Conductive Textile is associated with skin-electrode interface impedance located between the body (source of signal) and ECG monitoring device, thus affecting the recorded ECG quality. In this paper, we measure the skin-electrode impedance of Conductive Textile electrodes under various pressure levels, because in some applications ECG electrode is located under a blood pressure cuff and therefore it is under pressure when the cuff is inflated. We show that in fact under pressure the impedance decreases, resulting in a higher quality ECG measurement.
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Impact of Skin–Electrode Interface on Electrocardiogram Measurements Using Conductive Textile Electrodes
IEEE Transactions on Instrumentation and Measurement, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V Groza, Izmail BatkinAbstract:Physicians' understanding of biosignals as measured with medical instruments becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments' recordings exactly reflect what is happening in the patient's body so that the acquired signal is the real one or at least as close to the real in-body signal as possible. This is such an important issue that sometimes physicians use invasive measurements to obtain the real biosignal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this paper, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. To evaluate the performance of the device, we use it to measure ECG and apply Conductive Textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results, allowing us to investigate if ECG measured with the device is proper for applications where no skin preparation is allowed, such as ECG-assisted blood pressure monitoring devices. Next, we propose a method to reconstruct the ECG signal from the signal acquired by our device, with respect to the interface characteristics and their relation to the ECG. The interface in this paper is skin–electrode interface for Conductive Textiles. In the last stage of this paper, we explore the effects of pressure on skin–electrode interface impedance and its parametrical variation.
Bahareh Taji - One of the best experts on this subject based on the ideXlab platform.
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Effect of Pressure on Skin-Electrode Impedance in Wearable Biomedical Measurement Devices
IEEE Transactions on Instrumentation and Measurement, 2018Co-Authors: Bahareh Taji, Adrian D. C. Chan, Shervin ShirmohammadiAbstract:Objective: This paper investigates the effect of applied pressure on the skin-electrode impedance. Applied pressure, which affects the skin-electrode impedance, can fluctuate in many acquisition setups, particularly in wearable devices. The skin-electrode impedance, in turn, impacts the quality of the recorded signal in biomedical monitoring devices. Methods: Three types of electrodes were examined: Ag/AgCl electrodes, Conductive Textile electrodes, and dry electrodes with surface microfeatures (Orbital Research Inc.). Impedance measurements were conducted as pressure was repeatedly applied ( $P = 4$ kPa) and removed ( $P = 0$ kPa) over several trials. A Cole–Cole impedance model was utilized to model the skin-electrode interface. Significance and Results: Results demonstrated large decreases in the skin-electrode impedance of dry electrodes (Conductive Textile and orbital electrodes), especially with the initial application of the pressure. Model parameters also proved to be highly dependent on the level of pressure in dry electrodes but less dependent and more stable in wet electrodes. Decreases in skin-electrode impedance associated with applied pressure were thought to be caused by an increased effective electrode contact area. Changes in skin-electrode impedance were irreversible, lasting even after the applied pressure was released. Differences skin-electrode impedance associated with changes in applied pressure, decreased as the number of trials increased. Conclusion: Applied pressure has larger effect on dry electrodes than wet electrodes. Wearable devices that employ dry electrodes may have poorer biomedical signal quality when initially donned; however, the advantage of wet electrodes with their lower sensitivity to applied pressure is diminished in long-term monitoring applications.
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impact of skin electrode interface on electrocardiogram measurements using Conductive Textile electrodes
IEEE Transactions on Instrumentation and Measurement, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V Groza, Izmail BatkinAbstract:Physicians' understanding of biosignals as measured with medical instruments becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments' recordings exactly reflect what is happening in the patient's body so that the acquired signal is the real one or at least as close to the real in-body signal as possible. This is such an important issue that sometimes physicians use invasive measurements to obtain the real biosignal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this paper, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. To evaluate the performance of the device, we use it to measure ECG and apply Conductive Textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results, allowing us to investigate if ECG measured with the device is proper for applications where no skin preparation is allowed, such as ECG-assisted blood pressure monitoring devices. Next, we propose a method to reconstruct the ECG signal from the signal acquired by our device, with respect to the interface characteristics and their relation to the ECG. The interface in this paper is skin–electrode interface for Conductive Textiles. In the last stage of this paper, we explore the effects of pressure on skin–electrode interface impedance and its parametrical variation.
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measuring skin electrode impedance variation of Conductive Textile electrodes under pressure
The Journal of Thoracic and Cardiovascular Surgery, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V GrozaAbstract:Electrocardiogram (ECG) is the first bio-signal physicians use to diagnose cardiovascular diseases, since any kind of heart abnormality reflects on it. ECG electrodes play an important role in collecting this signal. One type of ECG electrodes which is recently getting more popular, especially due to its user friendly features compared to traditional Ag/AgCl electrodes, is Conductive Textile. Similar to any other type of electrode, Conductive Textile is associated with skin-electrode interface impedance located between the body (source of signal) and ECG monitoring device, thus affecting the recorded ECG quality. In this paper, we measure the skin-electrode impedance of Conductive Textile electrodes under various pressure levels, because in some applications ECG electrode is located under a blood pressure cuff and therefore it is under pressure when the cuff is inflated. We show that in fact under pressure the impedance decreases, resulting in a higher quality ECG measurement.
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I2MTC - Measuring skin-electrode impedance variation of Conductive Textile electrodes under pressure
2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V GrozaAbstract:Electrocardiogram (ECG) is the first bio-signal physicians use to diagnose cardiovascular diseases, since any kind of heart abnormality reflects on it. ECG electrodes play an important role in collecting this signal. One type of ECG electrodes which is recently getting more popular, especially due to its user friendly features compared to traditional Ag/AgCl electrodes, is Conductive Textile. Similar to any other type of electrode, Conductive Textile is associated with skin-electrode interface impedance located between the body (source of signal) and ECG monitoring device, thus affecting the recorded ECG quality. In this paper, we measure the skin-electrode impedance of Conductive Textile electrodes under various pressure levels, because in some applications ECG electrode is located under a blood pressure cuff and therefore it is under pressure when the cuff is inflated. We show that in fact under pressure the impedance decreases, resulting in a higher quality ECG measurement.
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Impact of Skin–Electrode Interface on Electrocardiogram Measurements Using Conductive Textile Electrodes
IEEE Transactions on Instrumentation and Measurement, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V Groza, Izmail BatkinAbstract:Physicians' understanding of biosignals as measured with medical instruments becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments' recordings exactly reflect what is happening in the patient's body so that the acquired signal is the real one or at least as close to the real in-body signal as possible. This is such an important issue that sometimes physicians use invasive measurements to obtain the real biosignal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this paper, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. To evaluate the performance of the device, we use it to measure ECG and apply Conductive Textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results, allowing us to investigate if ECG measured with the device is proper for applications where no skin preparation is allowed, such as ECG-assisted blood pressure monitoring devices. Next, we propose a method to reconstruct the ECG signal from the signal acquired by our device, with respect to the interface characteristics and their relation to the ECG. The interface in this paper is skin–electrode interface for Conductive Textiles. In the last stage of this paper, we explore the effects of pressure on skin–electrode interface impedance and its parametrical variation.
Shervin Shirmohammadi - One of the best experts on this subject based on the ideXlab platform.
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Effect of Pressure on Skin-Electrode Impedance in Wearable Biomedical Measurement Devices
IEEE Transactions on Instrumentation and Measurement, 2018Co-Authors: Bahareh Taji, Adrian D. C. Chan, Shervin ShirmohammadiAbstract:Objective: This paper investigates the effect of applied pressure on the skin-electrode impedance. Applied pressure, which affects the skin-electrode impedance, can fluctuate in many acquisition setups, particularly in wearable devices. The skin-electrode impedance, in turn, impacts the quality of the recorded signal in biomedical monitoring devices. Methods: Three types of electrodes were examined: Ag/AgCl electrodes, Conductive Textile electrodes, and dry electrodes with surface microfeatures (Orbital Research Inc.). Impedance measurements were conducted as pressure was repeatedly applied ( $P = 4$ kPa) and removed ( $P = 0$ kPa) over several trials. A Cole–Cole impedance model was utilized to model the skin-electrode interface. Significance and Results: Results demonstrated large decreases in the skin-electrode impedance of dry electrodes (Conductive Textile and orbital electrodes), especially with the initial application of the pressure. Model parameters also proved to be highly dependent on the level of pressure in dry electrodes but less dependent and more stable in wet electrodes. Decreases in skin-electrode impedance associated with applied pressure were thought to be caused by an increased effective electrode contact area. Changes in skin-electrode impedance were irreversible, lasting even after the applied pressure was released. Differences skin-electrode impedance associated with changes in applied pressure, decreased as the number of trials increased. Conclusion: Applied pressure has larger effect on dry electrodes than wet electrodes. Wearable devices that employ dry electrodes may have poorer biomedical signal quality when initially donned; however, the advantage of wet electrodes with their lower sensitivity to applied pressure is diminished in long-term monitoring applications.
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impact of skin electrode interface on electrocardiogram measurements using Conductive Textile electrodes
IEEE Transactions on Instrumentation and Measurement, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V Groza, Izmail BatkinAbstract:Physicians' understanding of biosignals as measured with medical instruments becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments' recordings exactly reflect what is happening in the patient's body so that the acquired signal is the real one or at least as close to the real in-body signal as possible. This is such an important issue that sometimes physicians use invasive measurements to obtain the real biosignal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this paper, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. To evaluate the performance of the device, we use it to measure ECG and apply Conductive Textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results, allowing us to investigate if ECG measured with the device is proper for applications where no skin preparation is allowed, such as ECG-assisted blood pressure monitoring devices. Next, we propose a method to reconstruct the ECG signal from the signal acquired by our device, with respect to the interface characteristics and their relation to the ECG. The interface in this paper is skin–electrode interface for Conductive Textiles. In the last stage of this paper, we explore the effects of pressure on skin–electrode interface impedance and its parametrical variation.
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measuring skin electrode impedance variation of Conductive Textile electrodes under pressure
The Journal of Thoracic and Cardiovascular Surgery, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V GrozaAbstract:Electrocardiogram (ECG) is the first bio-signal physicians use to diagnose cardiovascular diseases, since any kind of heart abnormality reflects on it. ECG electrodes play an important role in collecting this signal. One type of ECG electrodes which is recently getting more popular, especially due to its user friendly features compared to traditional Ag/AgCl electrodes, is Conductive Textile. Similar to any other type of electrode, Conductive Textile is associated with skin-electrode interface impedance located between the body (source of signal) and ECG monitoring device, thus affecting the recorded ECG quality. In this paper, we measure the skin-electrode impedance of Conductive Textile electrodes under various pressure levels, because in some applications ECG electrode is located under a blood pressure cuff and therefore it is under pressure when the cuff is inflated. We show that in fact under pressure the impedance decreases, resulting in a higher quality ECG measurement.
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I2MTC - Measuring skin-electrode impedance variation of Conductive Textile electrodes under pressure
2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V GrozaAbstract:Electrocardiogram (ECG) is the first bio-signal physicians use to diagnose cardiovascular diseases, since any kind of heart abnormality reflects on it. ECG electrodes play an important role in collecting this signal. One type of ECG electrodes which is recently getting more popular, especially due to its user friendly features compared to traditional Ag/AgCl electrodes, is Conductive Textile. Similar to any other type of electrode, Conductive Textile is associated with skin-electrode interface impedance located between the body (source of signal) and ECG monitoring device, thus affecting the recorded ECG quality. In this paper, we measure the skin-electrode impedance of Conductive Textile electrodes under various pressure levels, because in some applications ECG electrode is located under a blood pressure cuff and therefore it is under pressure when the cuff is inflated. We show that in fact under pressure the impedance decreases, resulting in a higher quality ECG measurement.
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Impact of Skin–Electrode Interface on Electrocardiogram Measurements Using Conductive Textile Electrodes
IEEE Transactions on Instrumentation and Measurement, 2014Co-Authors: Bahareh Taji, Shervin Shirmohammadi, V Groza, Izmail BatkinAbstract:Physicians' understanding of biosignals as measured with medical instruments becomes the foundation of their decisions and diagnoses of patients, as they rely strongly on what the instruments show. Thus, it is critical and very important to ensure that the instruments' recordings exactly reflect what is happening in the patient's body so that the acquired signal is the real one or at least as close to the real in-body signal as possible. This is such an important issue that sometimes physicians use invasive measurements to obtain the real biosignal. Generating an in-body signal from what a measurement device shows is called “signal purification” or “reconstruction” and can be done only when we have adequate information about the interface between the body and the monitoring device. In this paper, first, we present a device that we developed for electrocardiogram (ECG) acquisition and transfer to PC. To evaluate the performance of the device, we use it to measure ECG and apply Conductive Textile as our ECG electrode. Then, we evaluate ECG signals captured by different electrodes, specifically traditional gel Ag/AgCl and dry golden plate electrodes, and compare the results, allowing us to investigate if ECG measured with the device is proper for applications where no skin preparation is allowed, such as ECG-assisted blood pressure monitoring devices. Next, we propose a method to reconstruct the ECG signal from the signal acquired by our device, with respect to the interface characteristics and their relation to the ECG. The interface in this paper is skin–electrode interface for Conductive Textiles. In the last stage of this paper, we explore the effects of pressure on skin–electrode interface impedance and its parametrical variation.
Xing Xie - One of the best experts on this subject based on the ideXlab platform.
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Symmetrical MnO2–Carbon Nanotube–Textile Nanostructures for Wearable Pseudocapacitors with High Mass Loading
ACS Nano, 2011Co-Authors: Xing Xie, Mauro Pasta, Husam N Alshareef, Yuan Yang, Nian Liu, Yan Yao, Yi CuiAbstract:While MnO2 is a promising material for pseudocapacitor applications due to its high specific capacity and low cost, MnO2 electrodes suffer from their low electrical and ionic conductivities. In this article, we report a structure where MnO2 nanoflowers were conformally electrodeposited onto carbon nanotube (CNT)-enabled Conductive Textile fibers. Such nanostructures effectively decrease the ion diffusion and charge transport resistance in the electrode. For a given areal mass loading, the thickness of MnO2 on Conductive Textile fibers is much smaller than that on a flat metal substrate. Such a porous structure also allows a large mass loading, up to 8.3 mg/cm2, which leads to a high areal capacitance of 2.8 F/cm2 at a scan rate of 0.05 mV/s. Full cells were demonstrated, where the MnO2–CNT–Textile was used as a positive electrode, reduced MnO2–CNT–Textile as a negative electrode, and 0.5 M Na2SO4 in water as the electrolyte. The resulting pseudocapacitor shows promising results as a low-cost energy storag...
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symmetrical mno2 carbon nanotube Textile nanostructures for wearable pseudocapacitors with high mass loading
ACS Nano, 2011Co-Authors: Xing Xie, Mauro Pasta, Husam N Alshareef, Yuan Yang, Nian Liu, Yan Yao, Yi CuiAbstract:While MnO2 is a promising material for pseudocapacitor applications due to its high specific capacity and low cost, MnO2 electrodes suffer from their low electrical and ionic conductivities. In this article, we report a structure where MnO2 nanoflowers were conformally electrodeposited onto carbon nanotube (CNT)-enabled Conductive Textile fibers. Such nanostructures effectively decrease the ion diffusion and charge transport resistance in the electrode. For a given areal mass loading, the thickness of MnO2 on Conductive Textile fibers is much smaller than that on a flat metal substrate. Such a porous structure also allows a large mass loading, up to 8.3 mg/cm2, which leads to a high areal capacitance of 2.8 F/cm2 at a scan rate of 0.05 mV/s. Full cells were demonstrated, where the MnO2–CNT–Textile was used as a positive electrode, reduced MnO2–CNT–Textile as a negative electrode, and 0.5 M Na2SO4 in water as the electrolyte. The resulting pseudocapacitor shows promising results as a low-cost energy storag...