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Yasir F. Joya

Bio: Yasir F. Joya is an academic researcher from Ghulam Ishaq Khan Institute of Engineering Sciences and Technology. The author has contributed to research in topics: Anatase & Excimer laser. The author has an hindex of 10, co-authored 26 publications receiving 772 citations. Previous affiliations of Yasir F. Joya include Bangor University & Leiden University.

Papers
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TL;DR: An overview of the recent progress in electrochemical and photo-electrocatalytic water splitting devices is presented, using both molecular water oxidation complexes (WOCs) and nano-structured assemblies to develop an artificial photosynthetic system.
Abstract: The development of new energy materials that can be utilized to make renewable and clean fuels from abundant and easily accessible resources is among the most challenging and demanding tasks in science today. Solar-powered catalytic water-splitting processes can be exploited as a source of electrons and protons to make clean renewable fuels, such as hydrogen, and in the sequestration of CO2 and its conversion into low-carbon energy carriers. Recently, there have been tremendous efforts to build up a stand-alone solar-to-fuel conversion device, the "artificial leaf", using light and water as raw materials. An overview of the recent progress in electrochemical and photo-electrocatalytic water splitting devices is presented, using both molecular water oxidation complexes (WOCs) and nano-structured assemblies to develop an artificial photosynthetic system.

405 citations

Journal ArticleDOI
TL;DR: In this article, the effect of chemical and thermal reduction on the quality of chemically synthesized graphene and its derivatives was explored using Raman spectroscopy and X-ray diffraction, field emission scanning electron microscopy (FESEM) and atomic force microscopy.
Abstract: Large-scale fabrication of graphene and reduced graphene oxide (rGO) is important for industrial and research applications of this material. Chemical solution methods offer a low-cost alternate to produce rGO with high yield. This research is to explore the effect of chemical and thermal reduction on the quality of chemically synthesized graphene and its derivatives. A top-down process involved the chemical oxidation of the precursor graphite powder (size ~10 μm) using a concentrated mixture of sulphuric acid and nitric acid. Oxidized graphite powder was thermally exfoliated at 1,050°C for 30 s to produce graphene oxide (GO). Chemical reduction in GO sheets with sodium borohydride led to the formation of rGO. Characterization by Raman spectroscopy revealed an intensity ratio of 2D/G bands of rGO as approximately 0.5 indicating a multi-layered structure. X-ray diffraction, field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) results indicated a multi-layered rGO wit...

86 citations

Journal ArticleDOI
TL;DR: In this article, the Fortschritte bei elektrochemischen and photoelektrokatalytischen Wasserspaltungssystemen vorgestellt, die sowohl Wasser oxidierende molekulare Komplexe al as well as auch nanostrukturierte Anordnungen zur Entwicklung eines knstlichen Photosyntheseapparats nutzen.
Abstract: Die Erschliesung von erneuerbaren Ressourcen zur Herstellung sauberer Brennstoffe aus reichlich vorhandenen und einfach zugng- lichen Ressourcen zhlt derzeit zu den anspruchsvollsten Aufgaben der Wissenschaft. Katalytische Prozesse zur Wasserspaltung mithilfe von Solarenergie kcnnen als Quelle fr Elektronen und Protonen zur Erzeugung sauberer Brennstoffe wie Wasserstoff sowie zur Seques- trierung von CO2 und dessen Umwandlung in kohlenstoffarme En- ergietrger genutzt werden. In letzter Zeit wurden grose Anstren- gungen unternommen, um ein eigenstndiges Element zur Umwand- lung von Solarenergie in Brennstoff zu bauen: ein "knstliches Blatt", das mit Licht und Wasser als Rohstoffen arbeitet. Hier werden jngste Fortschritte bei elektrochemischen und photoelektrokatalytischen Wasserspaltungssystemen vorgestellt, die sowohl Wasser oxidierende molekulare Komplexe als auch nanostrukturierte Anordnungen zur Entwicklung eines knstlichen Photosyntheseapparats nutzen.

59 citations

Journal ArticleDOI
TL;DR: In this paper, a brief overview of surface-immobilized molecular assemblies for electrochemical water oxidation is presented, and an analysis of recent progress in catalyst design and performance is provided, including systems integration of modules for future stand-alone solar-to-fuel conversion devices.
Abstract: Clean energy carriers obtained from renewable, earth-abundant materials and by using the virtually unlimited supply of sunlight have potential to serve as future sustainable power sources. A quest for new materials for oxygen evolution from catalytic water oxidation and carbon dioxide reduction, which aim to build up solar-to-fuel conversion devices that use water as raw material, has been developing during the last two decades. Most of the research in the field of materials science and chemistry has been focused on the development of inorganic materials and molecular complexes for water oxidation, in particular bioinspired catalytic systems. Recently, various molecular water-oxidation complexes with mono- or multinuclear catalytic sites have been tested for solution-phase dioxygen generation. Catalyst immobilization and functionalization on an electrode surface is required for electrocatalytic or photoelectrochemical water oxidation devices; however, there are only a few examples in which a molecular catalyst has been placed on a transparent conducting surface in an electro- or photoelectrochemical system. Herein, a brief overview of surface-immobilized molecular assemblies for electrochemical water oxidation is presented, and an analysis of recent progress in catalyst design and performance is provided, including systems integration of modules for future stand-alone solar-to-fuel conversion devices. A view on the thermodynamics features of various intermediates and the mechanism of OO bond formation in single-site complexes and binuclear water oxidation catalysts is also presented.

49 citations


Cited by
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Journal ArticleDOI
Jiewei Liu1, Lianfen Chen1, Hao Cui1, Jianyong Zhang1, Li Zhang1, Cheng-Yong Su1 
TL;DR: This review summarizes the use of metal-organic frameworks (MOFs) as a versatile supramolecular platform to develop heterogeneous catalysts for a variety of organic reactions, especially for liquid-phase reactions.
Abstract: This review summarizes the use of metal–organic frameworks (MOFs) as a versatile supramolecular platform to develop heterogeneous catalysts for a variety of organic reactions, especially for liquid-phase reactions. Following a background introduction about catalytic relevance to various metal–organic materials, crystal engineering of MOFs, characterization and evaluation methods of MOF catalysis, we categorize catalytic MOFs based on the types of active sites, including coordinatively unsaturated metal sites (CUMs), metalloligands, functional organic sites (FOS), as well as metal nanoparticles (MNPs) embedded in the cavities. Throughout the review, we emphasize the incidental or deliberate formation of active sites, the stability, heterogeneity and shape/size selectivity for MOF catalysis. Finally, we briefly introduce their relevance into photo- and biomimetic catalysis, and compare MOFs with other typical porous solids such as zeolites and mesoporous silica with regard to their different attributes, and provide our view on future trends and developments in MOF-based catalysis.

2,418 citations

Journal ArticleDOI
11 Jan 2017
TL;DR: In this article, the authors investigate progress towards photo-electrocatalytic water-splitting systems, with special emphasis on how they might be incorporated into photoelectrocaralyst systems.
Abstract: Sunlight is by far the most plentiful renewable energy resource, providing Earth with enough power to meet all of humanity's needs several hundred times over. However, it is both diffuse and intermittent, which presents problems regarding how best to harvest this energy and store it for times when the sun is not shining. Devices that use sunlight to split water into hydrogen and oxygen could be one solution to these problems, because hydrogen is an excellent fuel. However, if such devices are to become widely adopted, they must be cheap to produce and operate. Therefore, the development of electrocatalysts for water splitting that comprise only inexpensive, earth-abundant elements is critical. In this Review, we investigate progress towards such electrocatalysts, with special emphasis on how they might be incorporated into photoelectrocatalytic water-splitting systems and the challenges that remain in developing these devices. Splitting water is an attractive means by which energy — either electrical and/or light — is stored and consumed on demand. Active and efficient catalysts for anodic and cathodic reactions often require precious metals. This Review covers base-metal catalysts that can afford high performance in a more sustainable and available manner.

2,369 citations

Journal ArticleDOI
TL;DR: In this Review, recent progress in the synthesis and electrochemical application of transition metal carbides and nitrides for energy storage and conversion is summarized andvantages and benefits of nanostructuring are highlighted.
Abstract: High-performance electrode materials are the key to advances in the areas of energy conversion and storage (e.g., fuel cells and batteries). In this Review, recent progress in the synthesis and electrochemical application of transition metal carbides (TMCs) and nitrides (TMNs) for energy storage and conversion is summarized. Their electrochemical properties in Li-ion and Na-ion batteries as well as in supercapacitors, and electrocatalytic reactions (oxygen evolution and reduction reactions, and hydrogen evolution reaction) are discussed in association with their crystal structure/morphology/composition. Advantages and benefits of nanostructuring (e.g., 2D MXenes) are highlighted. Prospects of future research trends in rational design of high-performance TMCs and TMNs electrodes are provided at the end.

971 citations