Peter R. Makgwane is currently a Full Professor at the University of South Africa (UNISA) Institute of Catalysis and Energy Solutions (ICES) and an Extraordinary Professor of Chemistry at the University of the Western Cape (South Africa). He previously worked as a Principal Scientist (2011–2023) at the Council for Scientific and Industrial Research (CSIR, South Africa) in catalysis and advanced energy materials. He has a PhD in Chemistry specializing in heterogeneous catalysis from Nelson Mandela University (South Africa, 2010). He was a guest editorial board member for the Journal of Nanotechnology and Nanoscience (2014) and MDPI Catalyst (2021) in nanocatalysis and photocatalysis thematic issues. He published books for several renowned publishers on advanced materials spheres with diverse applications in environmental remediations, energy, and chemical conversions. Professor Makgwane is a well-published scholar of articles and book chapters in heterogeneous catalysis and photocatalysis with focused applications in renewable chemicals, energy, and environmental remediation.Naveen Kumar is currently an Associate Professor in the Department of Chemistry, Maharshi Dayanand University, Rohtak (India), and has 18 years of research experience. He is actively engaged in the field of material chemistry with focused research expertise in semiconductor photocatalysis, nanocomposite materials, and electrochemical sensing. He has published more than 110 articles in the journals of high repute. He also worked at Universitat Politècnica de València, Valencia (Spain), in an international research project entitled "Development of a new generation CIGS based solar cells" [NANICIS-269279] in 2013 and 2014. He has presented various research papers at various national and international conferences and also delivered invited lectures at various institutes. Prof. Kumar has published two books as editor with renowned publishers.David E. Motaung is a Full Professor of Physics at the University of the Free State (South Africa). He previously worked as the Principal Scientist for the Council for Scientific and Industrial Research (CSIR, South Africa) in 2007–2019 and also as a Full Professor of Physics (2019–2021) at the University of Limpopo, South Africa. He obtained his PhD in Physics from the University of the Western Cape, South Africa, in 2011. He has been rated in the Top 2% of Scientists in the World by Stanford University in 2022 and 2023. He has published more than 130 research articles in peer-reviewed journals including three review articles. He has also published more than 15 book chapters and edited one book on metal oxide semiconductors for gas chemical sensing and environmental monitoring.

• 1 An Introduction to Two-Dimensional (2D) Nanomaterials; 2 Defects and Vacancies Effects on the Optoelectronic Properties of Two-Dimensional Nanomaterials; 3 Methods for the Synthesis of Two-Dimensional Nanomaterials: Structure and Properties; 4 2D Metal Chalcogenides Gas Chemical Sensors; 5 Two-Dimensional Nanomaterials for Electrochemical Detection of Organic Wastewater Pollutants; 6 2D Metal Oxides and Their Heterostructures for Gas Chemical Sensing; 7 Two-Dimensional MXenes-Based Materials in Gas Chemical Sensors; 8 Two-Dimensional Nanomaterials for the Removal of Radioactive Toxic Environmental Pollutants; 9 Two-Dimensional Nanomaterials for the Removal of Gaseous Air Contaminants; 10 2D Metal Chalcogenides for Photodegradation and Disinfection of Wastewater Pollutants; 11 2D Metal–Organic Framework Nanocomposites for Removal of Organic Pollutants; 12 Two-Dimensional Nanomaterials for Antibacterial and Antimicrobial Activity for Water Contaminants Disinfection; 13 2D Metal Oxides and Their Heterostructures for Photodegradation of Organic Water Pollutants; 14 2D Graphene Nanocomposites for the Removal of Organic Pollutants; 15 2D Layered Double Hydroxides Nanomaterials for the Removal of Water Pollutants; 16 2D Graphitic Carbon Nitrides Hybrids for the Removal of Organic Water Pollutants; 17 2D MXenes Nanomaterials for the Removal of Organic Wastewater Contaminants

Peter R. Makgwane is currently a Full Professor at the University of South Africa (UNISA) Institute of Catalysis and Energy Solutions (ICES) and an Extraordinary Professor of Chemistry at the University of the Western Cape (South Africa). He previously worked as a Principal Scientist (2011–2023) at the Council for Scientific and Industrial Research (CSIR, South Africa) in catalysis and advanced energy materials. He has a PhD in Chemistry specializing in heterogeneous catalysis from Nelson Mandela University (South Africa, 2010). He was a guest editorial board member for the Journal of Nanotechnology and Nanoscience (2014) and MDPI Catalyst (2021) in nanocatalysis and photocatalysis thematic issues. He published books for several renowned publishers on advanced materials spheres with diverse applications in environmental remediations, energy, and chemical conversions. Professor Makgwane is a well-published scholar of articles and book chapters in heterogeneous catalysis and photocatalysis with focused applications in renewable chemicals, energy, and environmental remediation.Naveen Kumar is currently an Associate Professor in the Department of Chemistry, Maharshi Dayanand University, Rohtak (India), and has 18 years of research experience. He is actively engaged in the field of material chemistry with focused research expertise in semiconductor photocatalysis, nanocomposite materials, and electrochemical sensing. He has published more than 110 articles in the journals of high repute. He also worked at Universitat Politècnica de València, Valencia (Spain), in an international research project entitled "Development of a new generation CIGS based solar cells" [NANICIS-269279] in 2013 and 2014. He has presented various research papers at various national and international conferences and also delivered invited lectures at various institutes. Prof. Kumar has published two books as editor with renowned publishers.David E. Motaung is a Full Professor of Physics at the University of the Free State (South Africa). He previously worked as the Principal Scientist for the Council for Scientific and Industrial Research (CSIR, South Africa) in 2007–2019 and also as a Full Professor of Physics (2019–2021) at the University of Limpopo, South Africa. He obtained his PhD in Physics from the University of the Western Cape, South Africa, in 2011. He has been rated in the Top 2% of Scientists in the World by Stanford University in 2022 and 2023. He has published more than 130 research articles in peer-reviewed journals including three review articles. He has also published more than 15 book chapters and edited one book on metal oxide semiconductors for gas chemical sensing and environmental monitoring.

• 1 An Introduction to Two-Dimensional (2D) Nanomaterials; 2 Defects and Vacancies Effects on the Optoelectronic Properties of Two-Dimensional Nanomaterials; 3 Methods for the Synthesis of Two-Dimensional Nanomaterials: Structure and Properties; 4 2D Metal Chalcogenides Gas Chemical Sensors; 5 Two-Dimensional Nanomaterials for Electrochemical Detection of Organic Wastewater Pollutants; 6 2D Metal Oxides and Their Heterostructures for Gas Chemical Sensing; 7 Two-Dimensional MXenes-Based Materials in Gas Chemical Sensors; 8 Two-Dimensional Nanomaterials for the Removal of Radioactive Toxic Environmental Pollutants; 9 Two-Dimensional Nanomaterials for the Removal of Gaseous Air Contaminants; 10 2D Metal Chalcogenides for Photodegradation and Disinfection of Wastewater Pollutants; 11 2D Metal–Organic Framework Nanocomposites for Removal of Organic Pollutants; 12 Two-Dimensional Nanomaterials for Antibacterial and Antimicrobial Activity for Water Contaminants Disinfection; 13 2D Metal Oxides and Their Heterostructures for Photodegradation of Organic Water Pollutants; 14 2D Graphene Nanocomposites for the Removal of Organic Pollutants; 15 2D Layered Double Hydroxides Nanomaterials for the Removal of Water Pollutants; 16 2D Graphitic Carbon Nitrides Hybrids for the Removal of Organic Water Pollutants; 17 2D MXenes Nanomaterials for the Removal of Organic Wastewater Contaminants

Peter R. Makgwane is currently a Full Professor at the University of South Africa (UNISA) Institute of Catalysis and Energy Solutions (ICES) and an Extraordinary Professor of Chemistry at the University of the Western Cape (South Africa). He previously worked as a Principal Scientist (2011–2023) at the Council for Scientific and Industrial Research (CSIR, South Africa) in catalysis and advanced energy materials. He has a PhD in Chemistry specializing in heterogeneous catalysis from Nelson Mandela University (South Africa, 2010). He was a guest editorial board member for the Journal of Nanotechnology and Nanoscience (2014) and MDPI Catalyst (2021) in nanocatalysis and photocatalysis thematic issues. He published books for several renowned publishers on advanced materials spheres with diverse applications in environmental remediations, energy, and chemical conversions. Professor Makgwane is a well-published scholar of articles and book chapters in heterogeneous catalysis and photocatalysis with focused applications in renewable chemicals, energy, and environmental remediation.Naveen Kumar is currently an Associate Professor in the Department of Chemistry, Maharshi Dayanand University, Rohtak (India), and has 18 years of research experience. He is actively engaged in the field of material chemistry with focused research expertise in semiconductor photocatalysis, nanocomposite materials, and electrochemical sensing. He has published more than 110 articles in the journals of high repute. He also worked at Universitat Politècnica de València, Valencia (Spain), in an international research project entitled "Development of a new generation CIGS based solar cells" [NANICIS-269279] in 2013 and 2014. He has presented various research papers at various national and international conferences and also delivered invited lectures at various institutes. Prof. Kumar has published two books as editor with renowned publishers.David E. Motaung is a Full Professor of Physics at the University of the Free State (South Africa). He previously worked as the Principal Scientist for the Council for Scientific and Industrial Research (CSIR, South Africa) in 2007–2019 and also as a Full Professor of Physics (2019–2021) at the University of Limpopo, South Africa. He obtained his PhD in Physics from the University of the Western Cape, South Africa, in 2011. He has been rated in the Top 2% of Scientists in the World by Stanford University in 2022 and 2023. He has published more than 130 research articles in peer-reviewed journals including three review articles. He has also published more than 15 book chapters and edited one book on metal oxide semiconductors for gas chemical sensing and environmental monitoring.

• 1 An Introduction to Two-Dimensional (2D) Nanomaterials; 2 Defects and Vacancies Effects on the Optoelectronic Properties of Two-Dimensional Nanomaterials; 3 Methods for the Synthesis of Two-Dimensional Nanomaterials: Structure and Properties; 4 2D Metal Chalcogenides Gas Chemical Sensors; 5 Two-Dimensional Nanomaterials for Electrochemical Detection of Organic Wastewater Pollutants; 6 2D Metal Oxides and Their Heterostructures for Gas Chemical Sensing; 7 Two-Dimensional MXenes-Based Materials in Gas Chemical Sensors; 8 Two-Dimensional Nanomaterials for the Removal of Radioactive Toxic Environmental Pollutants; 9 Two-Dimensional Nanomaterials for the Removal of Gaseous Air Contaminants; 10 2D Metal Chalcogenides for Photodegradation and Disinfection of Wastewater Pollutants; 11 2D Metal–Organic Framework Nanocomposites for Removal of Organic Pollutants; 12 Two-Dimensional Nanomaterials for Antibacterial and Antimicrobial Activity for Water Contaminants Disinfection; 13 2D Metal Oxides and Their Heterostructures for Photodegradation of Organic Water Pollutants; 14 2D Graphene Nanocomposites for the Removal of Organic Pollutants; 15 2D Layered Double Hydroxides Nanomaterials for the Removal of Water Pollutants; 16 2D Graphitic Carbon Nitrides Hybrids for the Removal of Organic Water Pollutants; 17 2D MXenes Nanomaterials for the Removal of Organic Wastewater Contaminants