Tahir Saif | COMSATS Institute of Information Technology Lahore (original) (raw)
Papers by Tahir Saif
Journal of nanoscience and nanotechnology, 2021
A facile and peculiar synthesis strategy is designed for the fabrication of transparent superhydr... more A facile and peculiar synthesis strategy is designed for the fabrication of transparent superhydrophobic surfaces on simple glass substrate. The synthesis methodology comprises of two steps of hydrothermal treatment of cleaned glass substrate with ultrapure water as a solvent followed by coating of 1H, 1H, 2H, 2H-perflourooctyltriethoxysilane (POTS) also by hydrothermal treatment in hydrothermal reactor. The hydrothermal treatment of glass substrate lead to the nanostructured surface morphology consisting of nanofibers and a blend of nanofibers/nanoflakes. Aforesaid nanostructured surface morphology upon hydrophobic coating resulted in superhydrophobic properties, increasing the water contact angle (WCA) from 92.0° to as high as 145.3°. Moreover, the developed synthesis approach also resulted in the optical transparent superhydrophobic glass substrate thus offering an attractive methodology to employ for self-cleaning applications.
Journal of Nanoscience and Nanotechnology, 2021
In this investigation we report the formation of thin ZnO recombination barrier layer at TiO2/CdS... more In this investigation we report the formation of thin ZnO recombination barrier layer at TiO2/CdS interface aimed for the improvement in performance of CdS sensitized solar cell. The film was deposited upon nanocrystalline mesoporous TiO2 surface by following a simple chemical process and characterized, using UV-Visible spectroscopy, X-ray diffraction and electron dispersive X-ray measurements. The insertion of ZnO thin layer enhances the QDSC (Quantum dot sensitized solar cell) performance, contributed mainly by an increase in open circuit voltage (Voc) due to reduced electron back transfer from TiO2 conduction band. Moreover, the analysis of photovoltaic characteristics upon increasing the thickness of the ZnO film reveals that the ZnO recombination barrier layer with optimum thickness at porous TiO2/CdS interface proved to be an effective potential barrier for minimizing electron back recombination.
New Trends in Alloy Development, Characterization and Application, 2015
The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alar... more The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alarmingly with industrial progress and it is estimated to be around 300 billion dollars or 3 to 4.5% of the GNP of developed nations. Thousands of alloys have been developed to control corrosion, which is a major consideration in the development of new ferrous and non-ferrous alloys. Several corrosion control techniques such as inhibitor treatment, coatings, cathodic protection, alloying additions, and designing for corrosion protection have been developed to combat corrosion. Despite their merits, techniques such as inhibition treatment and coatings are limited by their adverse effect on the environment because of their volatile organic components. Due to an increasingly alarming carbon footprint, there is a growing global concern to keep the environment clean. Hence, a great need exists to replace the current control methods by ecofriendly methods. The potential of the green technology of hydrophobicity has therefore been exploited to control corrosion by fabricating hydrophobic surfaces on alloys and these surfaces have shown highly promising results. This technology offers a novel method to control corrosion of metals, alloys, polymers and composites.
High Temperature Corrosion, 2016
There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion... more There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion, erosion, and corrosion-resistant coatings for petroleum, chemical, aerospace industry, and processes encountering harsh environments such as paper and pulp equipment (the ball valve for high-pressure leaching). Whereas sufficient information on mechanical properties, such as abrasion, wear, and fatigue, has been gathered over the years, work on the resistance of these coatings to erosion and corrosion is seriously lacking. In the work reported, it has been shown that nanostructured TiO 2 coatings offer superior physical and mechanical properties compared to conventional TiO 2 coatings. Three different types of plasma-sprayed titanium dioxide coated samples on mild steel substrate were employed for investigation. The feedstocks used were Sulzer Metco nanopowders designated as AE 9340, AE 9342, and AE 9309. Powder 9340 was a precursor. The corrosion resistance of nanostructured TiO 2 coating was dictated largely by surface structure and morphology. The distribution and geometry of splat lamellae, contents of unmelted nanoparticles, and magnitude of porosity are the important factors that affect corrosion resistance. TiO 2 showed excellent resistance to corrosion in 3% NaCl. The maximum corrosion rate was observed to be 4 mils per year as shown by polarization potential and weight loss studies. The erosion-corrosion resistance of the plasmasprayed nanostructured titanium dioxide coatings depends largely upon the characteristics of feed powder and its reconstitution. Dense, uniform, and evenly dispersed nanostructured constituents provide a high coating integrity, which offers high resistance to erosion-corrosion. A mechanism of erosion-corrosion is explained in the chapter with a schematic diagram. The findings show that the nanostructured TiO2 coatings offer superior resistance to corrosion, erosion, and environmental degradation.
The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alar... more The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alarmingly with industrial progress and it is estimated to be around 300 billion dollars or 3 to 4.5% of the GNP of developed nations. Thousands of alloys have been developed to control corrosion, which is a major consideration in the development of new ferrous and non-ferrous alloys. Several corrosion control techniques such as inhibitor treatment, coatings, cathodic protection, alloying additions, and designing for corrosion protection have been developed to combat corrosion. Despite their merits, techniques such as inhibition treatment and coatings are limited by their adverse effect on the environment because of their volatile organic components. Due to an increasingly alarming carbon footprint, there is a growing global concern to keep the environment clean. Hence, a great need exists to replace the current control methods by ecofriendly methods. The potential of the green technology of hydrophobicity has therefore been exploited to control corrosion by fabricating hydrophobic surfaces on alloys and these surfaces have shown highly promising results. This technology offers a novel method to control corrosion of metals, alloys, polymers and composites.
Books by Tahir Saif
There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion... more There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion, erosion, and corrosion-resistant coatings for petroleum, chemical, aerospace industry, and processes encountering harsh environments such as paper and pulp equipment (the ball valve for high-pressure leaching). Whereas sufficient information on mechanical properties, such as abrasion, wear, and fatigue, has been gathered over the years, work on the resistance of these coatings to erosion and corrosion is seriously lacking. In the work reported, it has been shown that nanostructured TiO 2 coatings offer superior physical and mechanical properties compared to conventional TiO 2 coatings. Three different types of plasma-sprayed titanium dioxide coated samples on mild steel substrate were employed for investigation. The feedstocks used were Sulzer Metco nanopowders designated as AE 9340, AE 9342, and AE 9309. Powder 9340 was a precursor. The corrosion resistance of nanostructured TiO 2 coating was dictated largely by surface structure and morphology. The distribution and geometry of splat lamellae, contents of unmelted nanoparticles, and magnitude of porosity are the important factors that affect corrosion resistance. TiO 2 showed excellent resistance to corrosion in 3% NaCl. The maximum corrosion rate was observed to be 4 mils per year as shown by polarization potential and weight loss studies. The erosion-corrosion resistance of the plasmasprayed nanostructured titanium dioxide coatings depends largely upon the characteristics of feed powder and its reconstitution. Dense, uniform, and evenly dispersed nanostructured constituents provide a high coating integrity, which offers high resistance to erosion-corrosion. A mechanism of erosion-corrosion is explained in the chapter with a schematic diagram. The findings show that the nanostructured TiO2 coatings offer superior resistance to corrosion, erosion, and environmental degradation.
Journal of nanoscience and nanotechnology, 2021
A facile and peculiar synthesis strategy is designed for the fabrication of transparent superhydr... more A facile and peculiar synthesis strategy is designed for the fabrication of transparent superhydrophobic surfaces on simple glass substrate. The synthesis methodology comprises of two steps of hydrothermal treatment of cleaned glass substrate with ultrapure water as a solvent followed by coating of 1H, 1H, 2H, 2H-perflourooctyltriethoxysilane (POTS) also by hydrothermal treatment in hydrothermal reactor. The hydrothermal treatment of glass substrate lead to the nanostructured surface morphology consisting of nanofibers and a blend of nanofibers/nanoflakes. Aforesaid nanostructured surface morphology upon hydrophobic coating resulted in superhydrophobic properties, increasing the water contact angle (WCA) from 92.0° to as high as 145.3°. Moreover, the developed synthesis approach also resulted in the optical transparent superhydrophobic glass substrate thus offering an attractive methodology to employ for self-cleaning applications.
Journal of Nanoscience and Nanotechnology, 2021
In this investigation we report the formation of thin ZnO recombination barrier layer at TiO2/CdS... more In this investigation we report the formation of thin ZnO recombination barrier layer at TiO2/CdS interface aimed for the improvement in performance of CdS sensitized solar cell. The film was deposited upon nanocrystalline mesoporous TiO2 surface by following a simple chemical process and characterized, using UV-Visible spectroscopy, X-ray diffraction and electron dispersive X-ray measurements. The insertion of ZnO thin layer enhances the QDSC (Quantum dot sensitized solar cell) performance, contributed mainly by an increase in open circuit voltage (Voc) due to reduced electron back transfer from TiO2 conduction band. Moreover, the analysis of photovoltaic characteristics upon increasing the thickness of the ZnO film reveals that the ZnO recombination barrier layer with optimum thickness at porous TiO2/CdS interface proved to be an effective potential barrier for minimizing electron back recombination.
New Trends in Alloy Development, Characterization and Application, 2015
The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alar... more The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alarmingly with industrial progress and it is estimated to be around 300 billion dollars or 3 to 4.5% of the GNP of developed nations. Thousands of alloys have been developed to control corrosion, which is a major consideration in the development of new ferrous and non-ferrous alloys. Several corrosion control techniques such as inhibitor treatment, coatings, cathodic protection, alloying additions, and designing for corrosion protection have been developed to combat corrosion. Despite their merits, techniques such as inhibition treatment and coatings are limited by their adverse effect on the environment because of their volatile organic components. Due to an increasingly alarming carbon footprint, there is a growing global concern to keep the environment clean. Hence, a great need exists to replace the current control methods by ecofriendly methods. The potential of the green technology of hydrophobicity has therefore been exploited to control corrosion by fabricating hydrophobic surfaces on alloys and these surfaces have shown highly promising results. This technology offers a novel method to control corrosion of metals, alloys, polymers and composites.
High Temperature Corrosion, 2016
There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion... more There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion, erosion, and corrosion-resistant coatings for petroleum, chemical, aerospace industry, and processes encountering harsh environments such as paper and pulp equipment (the ball valve for high-pressure leaching). Whereas sufficient information on mechanical properties, such as abrasion, wear, and fatigue, has been gathered over the years, work on the resistance of these coatings to erosion and corrosion is seriously lacking. In the work reported, it has been shown that nanostructured TiO 2 coatings offer superior physical and mechanical properties compared to conventional TiO 2 coatings. Three different types of plasma-sprayed titanium dioxide coated samples on mild steel substrate were employed for investigation. The feedstocks used were Sulzer Metco nanopowders designated as AE 9340, AE 9342, and AE 9309. Powder 9340 was a precursor. The corrosion resistance of nanostructured TiO 2 coating was dictated largely by surface structure and morphology. The distribution and geometry of splat lamellae, contents of unmelted nanoparticles, and magnitude of porosity are the important factors that affect corrosion resistance. TiO 2 showed excellent resistance to corrosion in 3% NaCl. The maximum corrosion rate was observed to be 4 mils per year as shown by polarization potential and weight loss studies. The erosion-corrosion resistance of the plasmasprayed nanostructured titanium dioxide coatings depends largely upon the characteristics of feed powder and its reconstitution. Dense, uniform, and evenly dispersed nanostructured constituents provide a high coating integrity, which offers high resistance to erosion-corrosion. A mechanism of erosion-corrosion is explained in the chapter with a schematic diagram. The findings show that the nanostructured TiO2 coatings offer superior resistance to corrosion, erosion, and environmental degradation.
The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alar... more The corrosion phenomenon is as old as the age of the planet. The cost of corrosion has risen alarmingly with industrial progress and it is estimated to be around 300 billion dollars or 3 to 4.5% of the GNP of developed nations. Thousands of alloys have been developed to control corrosion, which is a major consideration in the development of new ferrous and non-ferrous alloys. Several corrosion control techniques such as inhibitor treatment, coatings, cathodic protection, alloying additions, and designing for corrosion protection have been developed to combat corrosion. Despite their merits, techniques such as inhibition treatment and coatings are limited by their adverse effect on the environment because of their volatile organic components. Due to an increasingly alarming carbon footprint, there is a growing global concern to keep the environment clean. Hence, a great need exists to replace the current control methods by ecofriendly methods. The potential of the green technology of hydrophobicity has therefore been exploited to control corrosion by fabricating hydrophobic surfaces on alloys and these surfaces have shown highly promising results. This technology offers a novel method to control corrosion of metals, alloys, polymers and composites.
There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion... more There has been a dramatic increase in recent years in a demand for tough, wearresistant, abrasion, erosion, and corrosion-resistant coatings for petroleum, chemical, aerospace industry, and processes encountering harsh environments such as paper and pulp equipment (the ball valve for high-pressure leaching). Whereas sufficient information on mechanical properties, such as abrasion, wear, and fatigue, has been gathered over the years, work on the resistance of these coatings to erosion and corrosion is seriously lacking. In the work reported, it has been shown that nanostructured TiO 2 coatings offer superior physical and mechanical properties compared to conventional TiO 2 coatings. Three different types of plasma-sprayed titanium dioxide coated samples on mild steel substrate were employed for investigation. The feedstocks used were Sulzer Metco nanopowders designated as AE 9340, AE 9342, and AE 9309. Powder 9340 was a precursor. The corrosion resistance of nanostructured TiO 2 coating was dictated largely by surface structure and morphology. The distribution and geometry of splat lamellae, contents of unmelted nanoparticles, and magnitude of porosity are the important factors that affect corrosion resistance. TiO 2 showed excellent resistance to corrosion in 3% NaCl. The maximum corrosion rate was observed to be 4 mils per year as shown by polarization potential and weight loss studies. The erosion-corrosion resistance of the plasmasprayed nanostructured titanium dioxide coatings depends largely upon the characteristics of feed powder and its reconstitution. Dense, uniform, and evenly dispersed nanostructured constituents provide a high coating integrity, which offers high resistance to erosion-corrosion. A mechanism of erosion-corrosion is explained in the chapter with a schematic diagram. The findings show that the nanostructured TiO2 coatings offer superior resistance to corrosion, erosion, and environmental degradation.