Renewable Materials and Green Technology Products

Environmental and Safety Aspects

Shrikaant Kulkarni, Ann Rose Abraham, A. K. Haghi, Shrikaant Kulkarni, Ann Rose Abraham, A. K. Haghi

• Publisher: Apple Academic Press
• Year: 2021
• ISBN:
  9781000090048
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Industrial & Technical Chemistry

Renewable Materials and Green Technology Products: Environmental and Safety Aspects looks at the design, manufacture, and use of efficient, effective, safe, and more environmentally benign chemical products and processes. It includes a broad range of application-based solutions to the development of renewable materials and green technology.

The latest trends in the green synthesis and properties of CNs are presented in the first chapter of this book for generating social awareness about sustainable developments. The book goes on to highlight the naissance and progressive trail of microwave-assisted synthesis of metal oxide nanoparticles, for a clean and green technology tool. Chapters discuss green technological alternatives for the global abatement of air pollution, effective use and treatment of water and wastewater, renewable power generation from solar PV cells, carbon-based nanomaterials synthesized using green protocol for sustainable development, green technologies that help to achieve economic development without harming the environment, technical solutions to cut down the quantum of N losses, conventional processing techniques in developing the bionanocomposites as the biocatalyst, and more.

CHAPTER 1

Green Synthesized Carbon-Based Nanomaterials: Synthesis and Properties

BINILA K. KORAH, NEENA JOHN PLATHANAM, ANU ROSE CHACKO, MAMATHA SUSAN PUNNOOSE, THOMAS ABRAHAM, and BEENA MATHEW*

School of Chemical Sciences, Mahatma Gandhi University, Kottayam, India

*Corresponding author. E-mail: [email protected]

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ABSTRACT

Green nanotechnology is based on the 12 principles of green chemistry to synthesize new nanomaterials to attain, health, economic, environmental, and social benefits. Carbon in its single entity and various forms has been used in technology and human life for many centuries. Since in the prehistoric times, carbon-based materials have been used as writing and drawing materials. In the past two and a half decades, carbon nanomaterials (CNs), especially carbon dots (CDs), carbon nanotubes (CNTs), graphene, fullerenes, and carbon nanodiamond (ND) have been used as efficient materials due to their exclusive properties. The new green methods and technologies associated with CNs are put forward by the researchers all over the world have opened exciting opportunities for the revolution of green nanotechnology. CNs such as graphene, fullerenes, CNTs, NDs, and CDs synthesized from renewable organic resources have gathered a considerable amount of attention due to their outstanding properties and applications. The latest trends in the green synthesis and properties of the CNs are presented here for generating social awareness about the sustainable developments.

1.1 INTRODUCTION

Carbon which is the main component of living organisms has the inherent potential of combining with other atoms forming stable useful compounds and making it distinctive in all aspects. This uniqueness of carbon has led to the creation of numerous stable forms in all dimensions including carbon dots (CDs), nanotubes, graphene, graphene oxide (GO), fullerenes, and nanodiamond (ND). The use of carbon-based materials in all fields started long time before and continues to be so in a faster rate. The high cost of raw material and the pollution affected to nature are the two main obstacles that minimize the growth of carbon-based nanomaterials toward sustainable development. In most cases, we depend on petroleum and fossil fuel based-precursors which are not eco-friendly and also have a high chance of depletion in the near future. Researchers have recognized this and started developing carbon based nanomaterials from natural precursors, which are renewable, inexpensive, and environment friendly.

This chapter deals with the synthesis and properties of carbon-based nanomaterials from green precursors including plants, microbes, biomolecules, and minerals. The use of these sources as the starting material and the synthesis methods adopted offers many advantages over other conventionally used chemical methods. Among the different carbon-based nanomaterials, the green synthesis and properties of CDs, carbon nanotubes (CNTs), graphene, GO, fullerenes, and NDs are given special emphasis in the following sections (Fig. 1.1). We hope that this chapter leads a brief viewpoint on the properties and future advantages of carbon-based nanomaterials synthesized using green routes.

FIGURE 1.1 Schematic representation of green synthesized carbon-based nanomaterials.

1.2 CARBON DOTS (CDS)

The preceding years have witnessed the development of CQDs, C-dots, or CDs outperforming other members of the carbon family. CDs have attracted a lot of attention due to their chemical inertness, resistance, high stability to photo-bleaching, bright fluorescence, low toxicity, excellent aqueous solubility, and biocompatibility. These accountable characteristics have caused them to be applied several fields including sensing,¹ bioimaging,² optoelectronic,³ and medicine.⁴ CDs are primarily zero-dimensional nanoparticles, defined by a quasi-spherical morphology and the characteristic size of <10 nm.⁵ In 2004, Xu et al. discovered fluorescent carbon nanoparticles inadvertently by an electrophoretic refinement of single-walled carbon nanotubes (SWCNTs).⁶ Quantum-sized CDs were reported by Sun et al. in 2006 from the aqueous solution of the PEG_1500N with carbon nanoparticles.⁵

In the beginning, the prepared CDs were of low quantum yield (QY) and limited solubility because the synthesis of CDs was limited to carbonaceous material. The recently developed CDs possess enhanced QY and high solubility. The green synthesized CDs involve toxic free precursors which boost up innovation by reducing pollution. The term “green precursors” refers to substances that are either naturally occurring or are derived from renewable natural products or processes.⁷ The actual carbon sources of CDs may be from artificial or natural sources. In fact, natural commodities have some advantages over synthetic carbon sources in the preparation of biomass CDs, such as low cost and high abundance. In recent years, many precursors have been identified for synthesis of CDs including graphite,⁸ grapheme,⁹ C₆₀,¹⁰ multi-walled carbon nanotubes (MWCNTs),¹¹ saccharides,¹² amino acid,¹³ citric acid,¹⁴ lauryl gallate,¹⁵ ammonium citrate,¹⁶ ethylene glycol,¹⁷ benzene,¹⁸ phenylene diamine,¹⁹ phytic acid,²⁰ EDTA,²¹ thiourea,²² human derivatives,²³ animal derivatives,²⁴ fruit sources,²⁵ vegetables,²⁶ leaves,²⁷ and waste materials.²⁸

Herein, we highlight the recent advances in CDs with particular emphasis on the synthetic methods and physiochemical properties. Despite some noteworthy advances, the large-scale utilization of the sustainable resources for fabricating CDs with desirable properties by facile methods is still a great challenge...