PHD
  1. Inorganic chemistry  1.1. Coordination chemistry  1.1.1. Ligand field theory  1.1.2. Crystal field theory  1.1.3. Molecular Orbital Theory for Coordination Compounds  1.1.4. Stability of Coordination Compounds  1.1.5. Electronic spectra of coordination compounds  1.1.6. Isomerism in Coordination Compounds  1.1.7. Kinetics and mechanism of coordination reactions  1.2. Organometallic Chemistry  1.2.1. Metal Carbonyls  1.2.2. Metal alkyl and aryl  1.2.3. Fischer and Schrock carbonaceans  1.2.4. Oxidative Addition and Reductive Elimination  1.2.5. Metal Hydrides  1.2.6. Catalysis by organometallic compounds  1.2.7. Metallocenes and Sandwich Complexes  1.2.8. CH activation  1.3. Solid state chemistry  1.3.1. Crystal structures and lattices  1.3.2. Band theory and electrical properties  1.3.3. Defects in the crystal  1.3.4. Synthesis of solid state materials  1.3.5. Magnetic and optical properties of solids  1.3.6. Superconductivity  1.3.7. Solid state ionics  1.4. Bio-inorganic chemistry  1.4.1. Metalloproteins and enzymes  1.4.2. Metal ion transport and storage  1.4.3. The role of metals in medicine  1.4.4. Bioinspired catalysis  1.4.5. Metal–DNA interactions  1.4.6. Metal Complexes in Medical Science  1.5. Lanthanides and Actinides  1.5.1. Electronic configuration and oxidation states in lanthanides and actinides  1.5.2. Spectral and Magnetic Properties in Lanthanides and Actinides  1.5.3. Separation and Extraction of Lanthanides and Actinides  1.5.4. Coordination chemistry of f-block elements  1.6. Main Group Chemistry  1.6.1. Chemistry of boron compounds  1.6.2. Chemistry of Silicon and Germanium Compounds  1.6.3. Chemistry of Phosphorus and Sulfur Compounds  1.6.4. Organosilicon chemistry  1.6.5. Noble Gas Chemistry
  2. Organic chemistry  2.1. Reaction mechanism  2.1.1. Nucleophilic substitution reactions  2.1.2. Electrophilic addition and substitution reactions  2.1.3. Elimination reactions  2.1.4. Rearrangement reactions  2.1.5. Radical reactions  2.1.6. Pericyclic Reactions  2.1.7. Photochemical reactions  2.2. Stereoscopic  2.2.1. Chirality and optical activity  2.2.2. Structural analysis  2.2.3. Stereoelectronic effects  2.2.4. Asymmetric synthesis  2.2.5. Dynamic Stereochemistry  2.3. Organometallic Chemistry in Organic Synthesis  2.3.1. Organolithium and organomagnesium reagents  2.3.2. Transition metal catalyzed coupling reactions  2.3.3. Palladium-catalyzed reactions  2.3.4. Olefin Metathesis  2.3.5. Gold and silver catalysis  2.4. Natural products chemistry  2.4.1. Alkaloids and terpenoids  2.4.2. Steroids and Flavonoids  2.4.3. Total synthesis of natural products  2.4.4. Biosynthesis of natural products  2.5. Supramolecular Chemistry  2.5.1. Host-Guest Chemistry  2.5.2. Self-assembly and molecular recognition  2.5.3. Supramolecular Catalysis  2.5.4. Molecular Machines
  3. Physical Chemistry  3.1. Thermodynamics  3.1.1. Laws of Thermodynamics  3.1.2. Chemical Potential and Equilibrium  3.1.3. Statistical thermodynamics  3.1.4. Non-equilibrium thermodynamics  3.2. Quantum Chemistry  3.2.1. Schrödinger equation and its applications  3.2.2. Molecular orbital theory  3.2.3. Density functional theory  3.2.4. Post-Hartree–Fock methods  3.3. Chemical kinetics  3.3.1. Reaction rate theory  3.3.2. Mechanism and rate laws  3.3.3. Catalysis and enzyme kinetics  3.3.4. Reaction dynamics  3.4. Spectroscopy and molecular structure  3.4.1. Infrared Spectroscopy  3.4.2. UV-visible spectroscopy  3.4.3. Nuclear Magnetic Resonance Spectroscopy  3.4.4. Mass Spectrometry  3.4.5. Raman Spectroscopy  3.5. Surface and Colloid Chemistry  3.5.1. Absorption and Catalysis  3.5.2. Surfactants and micelles  3.5.3. Colloidal Stability  3.5.4. Nanomaterials and Interfaces
  4. Analytical chemistry  4.1. Chromatography  4.1.1. Gas Chromatography  4.1.2. High Performance Liquid Chromatography  4.1.3. Thin Layer Chromatography  4.1.4. Ion Chromatography  4.2. Electroanalytical techniques  4.2.1. Voltammetry and Polarography  4.2.2. Conductometry and potentiometry  4.2.3. Colometry  4.3. Spectroscopic Methods  4.3.1. Atomic absorption spectroscopy  4.3.2. Fluorescence Spectroscopy  4.3.3. X-ray diffraction  4.3.4. Electron paramagnetic resonance spectroscopy  4.4. Chemometrics  4.4.1. Data processing and statistical methods  4.4.2. Multidisciplinary analysis  4.4.3. Machine Learning in Analytical Chemistry
  5. Theoretical and Computational Chemistry  5.1. Molecular dynamics simulation  5.2. Quantum chemistry methods  5.3. Computational drug design  5.4. Machine Learning in Chemistry  5.5. Ab initio molecular dynamics
  6. Biophysics and Medicinal Chemistry  6.1. Drug discovery and design  6.2. Enzyme kinetics and inhibition  6.3. Chemical biology approach  6.4. Protein-ligand interactions  6.5. Bioorthogonal chemistry
  7. Materials chemistry  7.1. Polymer chemistry  7.1.1. Polymerization mechanism  7.1.2. Functional Polymers  7.1.3. Biodegradable Polymer  7.1.4. Conducting and semiconducting polymers  7.2. Nano Chemistry  7.2.1. Nanoparticles and nanostructures  7.2.2. Carbon-based nanomaterials  7.2.3. Quantum dots  7.3. Energy and Environmental Chemistry  7.3.1. Battery and Fuel Cell Chemistry  7.3.2. Green chemistry and sustainable materials  7.3.3. Photocatalysis

PHD → Materials chemistry → Energy and Environmental Chemistry ↓


Green chemistry and sustainable materials


Green chemistry is a revolutionary approach in the field of chemical science, which focuses on designing products and processes that reduce the use and production of hazardous substances. It aims to make the chemical industry more sustainable by reducing its environmental impact. Sustainable materials, on the other hand, refer to materials that are designed to have a minimal ecological footprint by taking into account their entire life cycle from production to disposal. When integrated into energy and environmental chemistry, these concepts provide promising avenues for addressing environmental issues.

Principles of green chemistry

Green chemistry is guided by twelve fundamental principles developed by Paul Anastas and John Warner. These principles emphasize prevention, atom economy, less hazardous chemical synthesis, designing safer chemicals, energy efficiency, renewable feedstocks, and more. Here's a brief overview:

  • Prevention: It is better to prevent waste than to treat or clean it after it has been generated.
  • Atom economy: Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.
  • Less hazardous chemical synthesis: Methods should aim to use and produce substances that have little or no toxicity to human health and the environment.
  • Design of safer chemicals: Chemical products should be designed to achieve their desired function while minimizing toxicity.
  • Safe solvents and excipients: The use of excipients (e.g., solvents, separating agents) should be made unnecessary whenever possible and, if used, should be as harmless as possible.
  • Design for energy efficiency: Energy requirements should be identified for their environmental and economic impacts and minimized. Synthetic methods should be operated at ambient temperature and pressure.
  • Use of renewable feedstocks: Whenever technically and economically feasible, raw materials should not be exhaustible but renewable.
  • Minimize derivatization: Unnecessary derivatization (use of blocking groups, protecting/deprotecting, or temporary modification of physical/chemical processes) should be avoided as much as possible.
  • Catalysis: Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.
  • Design for degradation: Chemical products should be designed so that at the end of their life they decompose into harmless degradation products and do not persist in the environment.
  • Real-time analysis for pollution prevention: Analytical methods need to be further developed to monitor and control the process in real time before hazardous substances are formed.
  • Inherently safe chemicals for accident prevention: The materials and nature of substances used in the chemical process should be selected in such a way that the probability of chemical accidents, including emissions, explosions and fires, is minimized.

Durable material

Sustainable materials are designed to provide environmental, social and economic benefits while protecting public health and the environment throughout their life cycle. This includes extraction, production, transportation, use, and disposal or recycling. Sustainable materials can be classified into several types:

  • Biodegradable substances: These substances can decompose naturally by the action of microorganisms.
  • Recycled materials: Materials that have been reprocessed and reused.
  • Bio-based ingredients: Derived from renewable biological sources, such as plants and animals.
  • Non-toxic materials: Do not release harmful substances into the environment.

Examples of sustainable materials

Let's consider some examples of sustainable materials in different industries:

  • Polylactic acid (PLA): A biodegradable polymer made from renewable resources such as corn starch. It is widely used in packaging, disposable utensils, and medical implants.
  • Cellulose fibers: Derived from plants such as cotton, jute, and hemp, these fibers are sustainable alternatives to synthetic fibers such as polyester and nylon.
  • Bamboo: Rapidly renewable, bamboo is a sustainable alternative to wood, used in flooring, furniture and textiles.
  • Recycled steel and aluminium: Recycled metals consume less energy than their original production and reduce environmental pollution.

Working example: functional green chemistry

Visual example: reaction efficiency

Examining a common organic reaction, consider the synthesis of water (H2O) from hydrogen and oxygen. In conventional chemistry, atoms can be wasted in reactions, but green chemistry emphasizes maximum atom efficiency. Use an example to see how each atom in the reactant ends up in the product:

 2H2 + O2 → 2H2O

In this reaction all the hydrogen and oxygen atoms are efficiently used and no by-products are formed.

Case study: zeolites in catalysts

Zeolites are crystalline aluminosilicates that act as excellent catalysts in chemical reactions, such as the conversion of hydrocarbons into gasoline. They are favored for their high atom economy, selectivity, and reusability.

Consider the cracking process where long-chain hydrocarbons are converted into smaller, valuable molecules:

 C16H34 (hexadecane) → C8H18 (octane) + C8H16 (octene)

The use of zeolites allows for more efficient and environmentally friendly reactions, as they operate at lower temperatures than conventional processes.

Impact on energy and environmental chemistry

Energy production and use are critical issues affecting global environmental quality and economic prosperity. Green chemistry and sustainable materials offer routes to green energy solutions. Here are some implementations:

Biofuels as renewable energy

Biofuels, such as ethanol and biodiesel, are derived from renewable plant and animal materials. They provide a cleaner alternative to fossil fuels, producing fewer emissions. For example:

 C2H5OH + 3O2 → 2CO2 + 3H2O

The above reaction describes the combustion of ethanol. It releases energy with fewer carbon emissions than conventional fuel sources.

Durable solar cells

Solar cells convert sunlight into electricity, but often involve the use of non-renewable or toxic materials such as cadmium. Advances in green chemistry have introduced sustainable alternatives using organic photovoltaic materials or lead-free perovskite solar cells:

 CH3NH3PbI3 → High efficiency solar absorber (methanamine lead iodide)

A lead-free alternative can be created using tin to reduce environmental toxicity, making the production cycle much safer.

Applications of sustainable materials in the real world

Ecodesign in buildings

Sustainable materials play an important role in construction by increasing thermal insulation and reducing energy consumption. Examples include insulating hemp blocks, recycled steel and rapidly renewable woods such as bamboo:

 Fixture applied in construction: - Hempcrete insulation, which reduces heating and cooling needs - Use of recycled steel reduces energy and raw material usage - Use of bamboo for flooring, a rapidly renewable alternative to classical hardwood

Textiles and fashion industry

The fashion industry is notorious for pollution and waste. Adopting sustainable materials like organic cotton, recycled polyester and regenerated fibres like Tencel (derived from wood pulp) helps reduce environmental impact:

 Eco-friendly clothing: - Organic cotton reduces water consumption and pesticide use - Recycled polyester made from PET bottles, reducing the need for new raw materials - Tencel, sustainably sourced from wood pulp, biodegradable and manufactured with minimal water and chemicals

Challenges in the implementation of green chemistry and sustainable materials

Despite the benefits, there are challenges to widespread adoption. Some of these are:

  • High initial cost of green technologies.
  • Lack of awareness and education among stakeholders.
  • Regulatory barriers and lack of supportive policies.
  • Technical challenges in scaling up green processes.

To overcome these barriers, ongoing research, education, and policy making should focus on creating incentives and support structures for the adoption of green chemistry and sustainable materials.

Conclusion

The integration of green chemistry and sustainable materials into energy and environmental chemistry represents a significant shift toward addressing some of the world's most serious ecological challenges. By reducing hazardous substances and optimizing material efficiency, it is possible to develop innovative solutions that protect the environment and improve human health. Future advances in technology and policy must prioritize sustainability to achieve lasting environmental health and economic viability.


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