Dr. Yasir Faiz | Nanjing University (original) (raw)

Papers by Dr. Yasir Faiz

Journal of Trace Elements and Minerals, 2024

Introduction: Contamination of water is a critical threat to human health at a global level. Wate... more Introduction: Contamination of water is a critical threat to human health at a global level. Water pollutants, such as heavy metals, can have adverse effects on the well-being of humans, animals, and the natural ecosystem of a region. Study Area: Murree is the most visited tourist destination in Pakistan. The rural population of Murree uses natural spring water for drinking, household use, and irrigation. Methods: This study assessed the elemental concentration of water from 20 natural springs in Murree using Inductively Coupled Plasma Optical Emission Spectroscopy. Source apportionment and spatial distribution of heavy metals were assessed using statistical approaches such as Pearson's correlation coefficient, principal component analysis, and interpolation. The study assessed the quality of water for drinking and irrigation in Murree's natural spring water using the metal index, sodium absorption ratio, magnesium absorption ratio, percentage sodium, Kelly's ratio, and salinity hazard. The health risks associated with heavy metals were assessed by computing Average daily dose, Hazard quotient, Hazard Index, and Cancer Risk. Results: The mean concentration of metals in mgL-1 varied in the following order: Ca (51.23) > Na (22.3) > Mg (16.26) > Si (6.51) > K (1.59) > Se (1.17) > Sr (0.48) > Ba (0.209) > Al (0.060) > Li (0.015) > Zn (0.005) > Fe (0.0033) > Ni (0.0032) > Cr (0.001). Metal index was calculated for Al (0.3), Ba (0.29), Cr (0.024), Ni (0.14), Fe (0.004), Zn (0.002), Sr (0.07), Mg (0.32), and Ca (0.25), revealing low levels of metal pollution. The geology of the study area was identified as the primary source of heavy metals in the water. The estimated values of health hazards showed that ingestion is the primary exposure pathway, with children having a higher risk. The health hazards posed by the heavy metal contact from the waters of Murree are not alarming. Quality indices show that the irrigation water sourced from the natural springs is of satisfactory quality. Conclusion: The study concluded that the spring water of Murree has low concentrations of heavy metals; their concentration is dependent upon the geology of the study area and is good for drinking and irrigation.

Applied Surface Science, 2024

The fabrication of supercapacitors with outstanding performance is presented with a distinct defe... more The fabrication of supercapacitors with outstanding performance is presented with a distinct defect-rich nanostructures. A one-pot, energy-efficient method for synthesizing defective manganese dioxide nanowires doped with potassium (K 0.35 MnO2) was developed. The introduction of potassium ions at 35 % birnessite resulted in a significant increase in lattice defects and an improvement in conductivity. Addition of KOH induces a phase transition from α-MnO2 to δ-MnO2. These imperfections result in a greater quantity of active sites, which are crucial for the process of energy storage. The K 0.35 MnO2 structure demonstrates a 405F/g increased capacity at a current density of 1 A/g. The asymmetric supercapacitor (K 0.35 MnO2 /AC) that was manufactured exhibits a capacitance of 106.4F/g when operating at 1 A/g, while maintaining a maximum energy density of 71.5 Wh kg−1 and a power density of 672 W kg−1. Furthermore, 92.7 % of the initial capacitance of the device is retained even after 8,000 cycles at 20 A/g. This study presents novel insights into the production of defective materials for energy storage applications through the utilization of a one-pot process as opposed to the multi-step method. In order to produce high-performance supercapacitors for practical applications, the results indicate that defect engineering is a crucial factor.

Journal of trace elements and minerals, Apr 1, 2024

Environmental earth sciences, May 27, 2024

Nanotechnology, Apr 3, 2024

Materials science in semiconductor processing, Apr 1, 2024

Research Square (Research Square), Jan 4, 2024

The accurate measurement of cholesterol in clinical diagnosis is very important for precise monit... more The accurate measurement of cholesterol in clinical diagnosis is very important for precise monitoring of multiple disease biomarkers. The increased level of cholesterol in the human body results in various life-threatening diseases. This leads to a top-notch priority for designing and fabricating a novel highly stable and reliable electrocatalyst for the measurement of cholesterol. In this work, Co 3 O 4 nanosheets loaded with various amounts of CdS NPs (0.02, 0.026 and 0.033 mg) are prepared combining hydrothermal process and modified SILAR method. The developed Co 3 O 4 @CdS-3 (0.026 mg) electrode demonstrates excellent sensing capability towards cholesterol in a wide linear range from 250 to 5000 μM. The electrode shows an outstanding high sensitivity of 13564.8 μA mM − 1 cm − 2 which is much larger than the previously reported nanomaterials based non-enzymatic cholesterol biosensors. The Co 3 O 4 @CdS-3 exhibits lower detection limit of 0.001 μM with good reproducibility for a period of 4 weeks and good selectivity. Moreover, the electrode displays good sensitivity towards cholesterol detection in the real samples, suggesting a new path to design and develop Co 3 O 4 @CdS-based extremely sensitive non-enzymatic biosensors for practical utilization.

Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycle... more Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycles and high rates due to electrode degradations. In this prospective, an effective strategy is employed to develop advanced electrode materials for lithium-ion batteries (LIBs). In the present work, a mesoporous Co 3 O 4 @CdS hybrid sructure is developed and investigated as anode for LiBs. The hybrid structure owning porous nature and large specific surface area, provides an opportunity to boost the lithium storage capabilities of Co 3 O 4 nanorods. The Co 3 O 4 @CdS electrode delivers an initial discharge capacity of 1292 mA h g −1 at 0.1C and a very stable reversible capacity of 760 mA h g −1 over 200 cycles with a capacity retention rate of 92.7%. In addition, the electrode exhibits excellent cyclic stability even after 800 cycles and good rate performance as compared to previously reported electrodes. Moreover, density functional theory (DFT) and electrochemical impedance spectroscopy (EIS) confirm the enhanced kinetics of the Co 3 O 4 @CdS electrode. The efficient performance of the electrode may be due to the increased surface reactivity, abundant active sites/interfaces for rapid Li + ion diffusion and the synergy between Co 3 O 4 and CdS NPs. This work demonstrates that Co 3 O 4 @CdS hybrid structures have great potential for high performance batteries.

RSC Adv., 14, 11900-11907, 2024

Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycle... more Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycles and high rates due to electrode degradations. In this prospective, an effective strategy is employed to develop advanced electrode materials for lithium-ion batteries (LIBs). In the present work, a mesoporous Co3O4@CdS hybrid sructure is developed and investigated as anode for LiBs. The hybrid structure owning porous nature and large specific surface area, provides an opportunity to boost the lithium storage capabilities of Co3O4 nanorods. The Co3O4@CdS electrode delivers an initial discharge capacity of 1292 mAhg−1 at 0.1C and a very stable reversible capacity of 760 mAhg−1 over 200 cycles with a capacity retention rate of 92.7%. In addition, the electrode exhibits excellent cyclic stability even after 800 cycles and good rate performance as compared to previously reported electrodes. Moreover, density functional theory (DFT) and electrochemical impedance spectroscopy (EIS) confirm the enhanced kinetics of the Co3O4@CdS electrode. The efficient performance of the electrode may be due to the increased surface reactivity, abundant active sites/interfaces for rapid Li+ ion diffusion and the synergy between Co3O4 and CdS NPs. This work demonstrates that Co3O4@CdS hybrid structures have great potential for high performance batteries.

Environmental Research

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issu... more Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t 5% of AZNCT IAC is 46 min, which is considerably higher than the t 5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.

Environmental Research, Sep 1, 2023

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issu... more Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t 5% of AZNCT IAC is 46 min, which is considerably higher than the t 5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.

Journal of Environmental Science and Health, Part A, 2012

Thirteen road dust and four soil samples were analyzed using instrumental neutron activation anal... more Thirteen road dust and four soil samples were analyzed using instrumental neutron activation analysis (INAA) to determine the elemental composition of road dust collected from Islamabad Expressway. The amounts of most of the elements determined were generally in the lower range of the global data with the exception of Ce, Nd, Sn and Zr, which were measured at higher concentrations in Islamabad. The magnitudes of Enrichment Factors (EFs) showed that the area around Islamabad Expressway is low to moderately polluted especially by elements such as Mg and Sb. Elemental health risk was assessed through dose calculations for carcinogenic and non-carcinogenic metals; and by the determination of LADD (lifetime average daily dose). The carcinogenic metals studied showed the following variation in their LADD values; Cr>Ni>Co>Cd>As. Dose calculations for non-cancerous and cancerous elements showed the data obtained to lie within the safe threshold of 10(-3)-10(-6) mg kg(-1) day(-1) for most elements. The Soil-based elements Al, Fe, K, Mg, Na and Ti were the exception and originated from the exposed soil around the highway. Moreover highest Hazard Index (HI) was found to be associated with the presence of Al, Cr, Pb and V in road dust showing soil, transport and industry to be the major sources of road dust.

Journal of the Chemical Society of Pakistan, 2011

Applied Radiation and Isotopes, 2012

Multani mitti clay was studied for 19 essential and other elements. Four different radio-assay sc... more Multani mitti clay was studied for 19 essential and other elements. Four different radio-assay schemes were adopted for instrumental neutron activation analysis (INAA) using miniature neutron source reactor. The estimated weekly intakes of Cr and Fe are high for men, women, pregnant and lactating women and children while intake of Co is higher in adult categories and Mn by pregnant women. Comparison of MM clay with other type of clays shows that it is a good source of essential elements.

Journal of Trace Elements and Minerals, 2024

Introduction: Contamination of water is a critical threat to human health at a global level. Wate... more Introduction: Contamination of water is a critical threat to human health at a global level. Water pollutants, such as heavy metals, can have adverse effects on the well-being of humans, animals, and the natural ecosystem of a region. Study Area: Murree is the most visited tourist destination in Pakistan. The rural population of Murree uses natural spring water for drinking, household use, and irrigation. Methods: This study assessed the elemental concentration of water from 20 natural springs in Murree using Inductively Coupled Plasma Optical Emission Spectroscopy. Source apportionment and spatial distribution of heavy metals were assessed using statistical approaches such as Pearson's correlation coefficient, principal component analysis, and interpolation. The study assessed the quality of water for drinking and irrigation in Murree's natural spring water using the metal index, sodium absorption ratio, magnesium absorption ratio, percentage sodium, Kelly's ratio, and salinity hazard. The health risks associated with heavy metals were assessed by computing Average daily dose, Hazard quotient, Hazard Index, and Cancer Risk. Results: The mean concentration of metals in mgL-1 varied in the following order: Ca (51.23) > Na (22.3) > Mg (16.26) > Si (6.51) > K (1.59) > Se (1.17) > Sr (0.48) > Ba (0.209) > Al (0.060) > Li (0.015) > Zn (0.005) > Fe (0.0033) > Ni (0.0032) > Cr (0.001). Metal index was calculated for Al (0.3), Ba (0.29), Cr (0.024), Ni (0.14), Fe (0.004), Zn (0.002), Sr (0.07), Mg (0.32), and Ca (0.25), revealing low levels of metal pollution. The geology of the study area was identified as the primary source of heavy metals in the water. The estimated values of health hazards showed that ingestion is the primary exposure pathway, with children having a higher risk. The health hazards posed by the heavy metal contact from the waters of Murree are not alarming. Quality indices show that the irrigation water sourced from the natural springs is of satisfactory quality. Conclusion: The study concluded that the spring water of Murree has low concentrations of heavy metals; their concentration is dependent upon the geology of the study area and is good for drinking and irrigation.

Applied Surface Science, 2024

The fabrication of supercapacitors with outstanding performance is presented with a distinct defe... more The fabrication of supercapacitors with outstanding performance is presented with a distinct defect-rich nanostructures. A one-pot, energy-efficient method for synthesizing defective manganese dioxide nanowires doped with potassium (K 0.35 MnO2) was developed. The introduction of potassium ions at 35 % birnessite resulted in a significant increase in lattice defects and an improvement in conductivity. Addition of KOH induces a phase transition from α-MnO2 to δ-MnO2. These imperfections result in a greater quantity of active sites, which are crucial for the process of energy storage. The K 0.35 MnO2 structure demonstrates a 405F/g increased capacity at a current density of 1 A/g. The asymmetric supercapacitor (K 0.35 MnO2 /AC) that was manufactured exhibits a capacitance of 106.4F/g when operating at 1 A/g, while maintaining a maximum energy density of 71.5 Wh kg−1 and a power density of 672 W kg−1. Furthermore, 92.7 % of the initial capacitance of the device is retained even after 8,000 cycles at 20 A/g. This study presents novel insights into the production of defective materials for energy storage applications through the utilization of a one-pot process as opposed to the multi-step method. In order to produce high-performance supercapacitors for practical applications, the results indicate that defect engineering is a crucial factor.

Journal of trace elements and minerals, Apr 1, 2024

Environmental earth sciences, May 27, 2024

Nanotechnology, Apr 3, 2024

Materials science in semiconductor processing, Apr 1, 2024

Research Square (Research Square), Jan 4, 2024

The accurate measurement of cholesterol in clinical diagnosis is very important for precise monit... more The accurate measurement of cholesterol in clinical diagnosis is very important for precise monitoring of multiple disease biomarkers. The increased level of cholesterol in the human body results in various life-threatening diseases. This leads to a top-notch priority for designing and fabricating a novel highly stable and reliable electrocatalyst for the measurement of cholesterol. In this work, Co 3 O 4 nanosheets loaded with various amounts of CdS NPs (0.02, 0.026 and 0.033 mg) are prepared combining hydrothermal process and modified SILAR method. The developed Co 3 O 4 @CdS-3 (0.026 mg) electrode demonstrates excellent sensing capability towards cholesterol in a wide linear range from 250 to 5000 μM. The electrode shows an outstanding high sensitivity of 13564.8 μA mM − 1 cm − 2 which is much larger than the previously reported nanomaterials based non-enzymatic cholesterol biosensors. The Co 3 O 4 @CdS-3 exhibits lower detection limit of 0.001 μM with good reproducibility for a period of 4 weeks and good selectivity. Moreover, the electrode displays good sensitivity towards cholesterol detection in the real samples, suggesting a new path to design and develop Co 3 O 4 @CdS-based extremely sensitive non-enzymatic biosensors for practical utilization.

Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycle... more Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycles and high rates due to electrode degradations. In this prospective, an effective strategy is employed to develop advanced electrode materials for lithium-ion batteries (LIBs). In the present work, a mesoporous Co 3 O 4 @CdS hybrid sructure is developed and investigated as anode for LiBs. The hybrid structure owning porous nature and large specific surface area, provides an opportunity to boost the lithium storage capabilities of Co 3 O 4 nanorods. The Co 3 O 4 @CdS electrode delivers an initial discharge capacity of 1292 mA h g −1 at 0.1C and a very stable reversible capacity of 760 mA h g −1 over 200 cycles with a capacity retention rate of 92.7%. In addition, the electrode exhibits excellent cyclic stability even after 800 cycles and good rate performance as compared to previously reported electrodes. Moreover, density functional theory (DFT) and electrochemical impedance spectroscopy (EIS) confirm the enhanced kinetics of the Co 3 O 4 @CdS electrode. The efficient performance of the electrode may be due to the increased surface reactivity, abundant active sites/interfaces for rapid Li + ion diffusion and the synergy between Co 3 O 4 and CdS NPs. This work demonstrates that Co 3 O 4 @CdS hybrid structures have great potential for high performance batteries.

RSC Adv., 14, 11900-11907, 2024

Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycle... more Transition metal oxides based anodes are facing crucial problems of capacity fading at long cycles and high rates due to electrode degradations. In this prospective, an effective strategy is employed to develop advanced electrode materials for lithium-ion batteries (LIBs). In the present work, a mesoporous Co3O4@CdS hybrid sructure is developed and investigated as anode for LiBs. The hybrid structure owning porous nature and large specific surface area, provides an opportunity to boost the lithium storage capabilities of Co3O4 nanorods. The Co3O4@CdS electrode delivers an initial discharge capacity of 1292 mAhg−1 at 0.1C and a very stable reversible capacity of 760 mAhg−1 over 200 cycles with a capacity retention rate of 92.7%. In addition, the electrode exhibits excellent cyclic stability even after 800 cycles and good rate performance as compared to previously reported electrodes. Moreover, density functional theory (DFT) and electrochemical impedance spectroscopy (EIS) confirm the enhanced kinetics of the Co3O4@CdS electrode. The efficient performance of the electrode may be due to the increased surface reactivity, abundant active sites/interfaces for rapid Li+ ion diffusion and the synergy between Co3O4 and CdS NPs. This work demonstrates that Co3O4@CdS hybrid structures have great potential for high performance batteries.

Environmental Research

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issu... more Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t 5% of AZNCT IAC is 46 min, which is considerably higher than the t 5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.

Environmental Research, Sep 1, 2023

Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issu... more Removal of methyl iodide (CH3I) from the air present within nuclear facilities is a critical issue. In case of any nuclear accident, there is a great need to mitigate the radioactive organic iodide immediately as it accumulates in human bodies, causing severe consequences. Current research focuses on removing organic iodides, for which the surface of activated carbon (AC) was modified by impregnating it with different metals individually, i.e. Ag, Ni, Zn, Cu and with the novel combination of these four metals (AZNC). After the impregnation of metals, triethylenediamine (TEDA) was coated on metal impregnated activated carbon (IAC) surface. The adsorption capacity of the combination of four metals IAC was found to be 276 mg/g as the maximum for the trapping of CH3I. Whereas TEDA-metal impregnation on ACs enhanced the removal efficiency of CH3I up to 352 mg/g. After impregnation, adsorption capacity of AZNC and AZNCT is significantly higher as compared to AC. According to the finding, t 5% of AZNCT IAC is 46 min, which is considerably higher than the t 5% of other tested adsorbents. According to isotherm fitting data, Langmuir isotherm was found superior for describing CH3I sorption onto AC and IACs. Kinetics study shows that pseudo second order model represented the sorption of CH3I more accurately than the pseudo first order. Thermodynamic studies gave negative value of ΔG which shows that the reaction is spontaneous in nature. Based on the findings, AZNCT IAC appears to have a great potential for air purification applications in order to obtain clean environment.

Journal of Environmental Science and Health, Part A, 2012

Thirteen road dust and four soil samples were analyzed using instrumental neutron activation anal... more Thirteen road dust and four soil samples were analyzed using instrumental neutron activation analysis (INAA) to determine the elemental composition of road dust collected from Islamabad Expressway. The amounts of most of the elements determined were generally in the lower range of the global data with the exception of Ce, Nd, Sn and Zr, which were measured at higher concentrations in Islamabad. The magnitudes of Enrichment Factors (EFs) showed that the area around Islamabad Expressway is low to moderately polluted especially by elements such as Mg and Sb. Elemental health risk was assessed through dose calculations for carcinogenic and non-carcinogenic metals; and by the determination of LADD (lifetime average daily dose). The carcinogenic metals studied showed the following variation in their LADD values; Cr>Ni>Co>Cd>As. Dose calculations for non-cancerous and cancerous elements showed the data obtained to lie within the safe threshold of 10(-3)-10(-6) mg kg(-1) day(-1) for most elements. The Soil-based elements Al, Fe, K, Mg, Na and Ti were the exception and originated from the exposed soil around the highway. Moreover highest Hazard Index (HI) was found to be associated with the presence of Al, Cr, Pb and V in road dust showing soil, transport and industry to be the major sources of road dust.

Journal of the Chemical Society of Pakistan, 2011

Applied Radiation and Isotopes, 2012

Multani mitti clay was studied for 19 essential and other elements. Four different radio-assay sc... more Multani mitti clay was studied for 19 essential and other elements. Four different radio-assay schemes were adopted for instrumental neutron activation analysis (INAA) using miniature neutron source reactor. The estimated weekly intakes of Cr and Fe are high for men, women, pregnant and lactating women and children while intake of Co is higher in adult categories and Mn by pregnant women. Comparison of MM clay with other type of clays shows that it is a good source of essential elements.