اسلامی نقطہ نظر سے ماحولیاتی نظام کی پائیدار ترقی: ایک تحقیقی مطالعہ

In globalization and information age, Sustainable development is a contemporary issue to protect future generations. Islam is not only a religion, but also a guideline for whole life and is based on divine principles of Shari‘a that also address sustainable development to mankind. Indeed many values and principles that have been central to Islam are inclined towards prosperity of people and development of society. On other hand Industrial revolution brought a huge destruction on the earth because in capitalist system people are self concerned rather than society. Islamic social responsibility teaches lesson of unity and called a mankind an ummah (community) and a moderate ummah, who is not allowed to make any mischief on the earth. Everything on the earth is gifted by Allah to the mankind and man is the deputy of Allah and become a steward (khal┘fah) for the earth, now it is his responsibility to save the world from any harm. The main objective of this research is to present the principles and applications of Islam in sustainable development debate especially on ecological aspect.

Fabrication and Optimization of Cost Effective Higher Efficiency Third-Generation Solar Cells

Utilizing renewable energy is becoming a progressively vital task owing to concerns over fossil fuel supplies and further energy accessibility in the future. Photovoltaic technology offers a great potential to address this problem. The development of high efficiency solar cells and the production procedures that involve low capital expenditure are two objectives that essentially be met to meet the aggressive challenge of 7-10 TW installed photovoltaic capacity by 2030. The third-generation solar cell technology, such as, dyesensitized and perovskite solar cells have gained great consideration because of ease of their manufacturing, lower cost, higher efficiency and unique applications. In the present research work, fabrication and characterization of third generation solar cells is undertaken. Employing low cost azo dyes as sensitizers DSSCs are fabricated. In order to provide insight into their performance, time dependent density functional theory (TD-DFT), photovoltaic and impedance spectroscopic measurements were performed. Comparing the photovoltaic data with a DSSC using a different member of the azo family of dyes, open circuit voltage and fill factor of a device studied in this work are found higher by 33% and 104%, respectively. The performance is also compared with the DSSCs fabricated using forty-nine commercial mordant dyes and open circuit photovoltage of the device studied in this work is found higher. DSSCs are fabricated employing biochar based counter electrode, as a substitute to expensive platinum counter electrode. The highest efficiency of biochar based DSSC are found to be 8.6% in comparison to 7.58% for Pt one. The external quantum efficiencies recorded for both the devices are in agreement to the JV characterization. SEM is recorded to reveal the topology of the surface. EIS and cyclic voltammetry confirmed the better performance of biochar based counter electrode over platinum based one. DSSC is also fabricated using a low-cost carbon counter electrode made by placing a conducting glass over a candle flame. Photovoltaic properties and impedance spectroscopic measurements are performed. The photovoltaic parameters of the cell studied under simulated AM 1.5 illumination revealed open circuit voltage of 680 mV, short circuit current density of 5.8 mA.cm-2, and fill factor of 45%. Impedance spectroscopy was performed in order to get insight of cell performance. The impedance spectra are observed both voltage and frequency dependent. Photovoltaic and impedance spectroscopic studies were performed on the DSSCs fabricated employing N719 dye without and with chenodeoxycholic acid (CDCA) as additive. The co-adsorbent significantly enhanced the open circuit photovoltage (Voc), photocurrent density (Jsc) and the solar energy power conversion efficiency (h). The effect of additive on the impedance spectra is reported. Organic-inorganic hybrid perovskite solar cells (PSCs) of both p-i-n and n-i-p type structures are fabricated. The n-i-p structured PSC has exhibited better performance and provided a power conversion efficiency (PCE) of 15.07 % , short-circuit photocurrent density (Jsc) 17.35 mA.cm-2, open-circuit photovoltage (Voc) 1.03 V and fill factor (FF) 0.645. The p-i-n type device showed a relatively poor performance. Its photovoltaic parameters such as PCE, short-circuit photocurrent density, open-circuit photovoltage and fill factor are, 12.07%, 17.35 mA.cm-2, 0.87 V, and 0.799, respectively. Morphology of the prepared films for n-i-p is found out to be dense and made of crystalline grains as compared to p-i-n structure and more pin holes are observed in the p-i-n structure. The charge transport in the film and across the interface at the perovskite/charge transport layer is hampered by the high film roughness in p-i-n structured PSC, thus, resulting in low efficiency in comparison.