This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg −1 ) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage.
Carson, R. (1962) Silent Spring. Houghton Mifflin Co.
Lovelock, J.E., Maggs, R.J. and Wade, R.J. (1973) Halogenated Hydrocarbons in and over the Atlantic. Nature , 241, 194-196. https://doi.org/10.1038/241194a0
Lovelock, J.E. (1972) Gaia as Seen through the Atmosphere. Atmospheric Enviro n ment (1967), 6, 579-580. https://doi.org/10.1016/0004-6981(72)90076-5
NASA/Apollo 17 Crew. The Apollo 17 Full Earth Known as the Blue Marble. Source NASA, Flickr.com Project Apollo Archive. https://www.flickr.com/photos/projectapolloarchive
Drasar, P. (1991) Green Chemistry—Dream or Reality (Minimum Impact Chemistry). Chemické Listy , 85, 1144-1149.
Anastas, P.T. (1994) Benign by Design Chemistry. In: Anastas, P.T. and Farris, C.A., Eds., Benign by Design : Alternative Synthetic Design for Pollution Prevention , ACS Symposium Series 577, American Chemical Society, 2-22.
Anastas, P.T. and Warner, J.A. (1998) Green Chemistry: Theory and Practice. Oxford University Press.
Gedye, R.N., Smith, F. and Westaway, K.C. (1988) The Rapid Synthesis of Organic Compounds in Microwave ovens. Canadian Journal Chemistry , 66, 17-26.
Gedye, R.N., Rank, W. and Westaway, K.C. (1991) The Rapid Synthesis of Organic Compounds in Microwave Ovens. II. Canadian Journal Chemistry , 69, 706-711.
Sheldon, R.A. (2008) E Factors, Green Chemistry and Catalysis: An Odyssey. Chemical Communications , 29, 3352-3365. https://doi.org/10.1039/b803584a
Sheldon, R.A. (2017) Metrics of Green Chemistry and Sustainability: Past, Present, and Future. ACS Sustainable Chemistry & Engineering , 6, 32-48. https://doi.org/10.1021/acssuschemeng.7b03505
Abdussalam-Mohammeda, W., Alia, A.Q. and Errayes, A.O. (2020) Green Chemistry: Principles, Applications, and Disadvantages. Chemical Methodologies , 4, 408-423.
Santra, S., Rahman, M., Roy, A., Majee, A. and Hajra, A. (2014) Microwave-Assisted Three-Component “Catalyst and Solvent-Free” Green Protocol: A Highly Efficient and Clean One-Pot Synthesis of Tetrahydrobenzo[b]pyrans. Organic Chemistry I n ternational , 2014, Article ID: 851924.
Gabano, E. and Ravera, M. (2022) Microwave-Assisted Synthesis: Can Transition Metal Complexes Take Advantage of This “Green” Method? Molecules , 27, Article No. 4249. https://doi.org/10.3390/molecules27134249
Sheldon, R.A. (2023) The E Factor at 30: A Passion for Pollution Prevention. Green Chemistry , 25, 1704-1728.
Law, V.J. and Dowling, D.P. (2023) Microwave-Assisted Au and Ag Nanoparticle Synthesis: An Energy Phase-Space Projection Analysis. American Journal of An a lytical Chemistry , 14, 149-174. https://doi.org/10.4236/ajac.2023.144009
Law, V.J. and Dowling, D.P. (2023) Microwave-Assisted Transition Metal Nanostructure Synthesis: Power-Law Signature Verification. American Journal of An a lytical Chemistry , 14, 326-349. https://doi.org/10.4236/ajac.2023.148018
Law, V.J. and Dowling, D.P. (2023) Green Chemistry Allometry Test of Microwave-Assisted Synthesis of Transition Metal Nanostructures. American Journal of Analytical Chemistry , 14, 493-518. https://doi.org/10.4236/ajac.2023.1411029
Bondarenko, O., Juganson, K., Ivask, A., Kasemets, K. and Mortimer, M. (2013) Toxicity of Ag, CuO and ZnO Nanoparticles to Selected Environmentally Relevant Test Organisms and Mammalian Cells in Vitro : A Critical Review. Archives of To x icology , 87, 1181-1200.
Cai, Y. and Huang, J. (2023) Preparation and Photocatalysis Characteristics of Flower-Like ZnO by Microwave Method. Journal of Physics : Conference Series , 2437, Article ID: 012039. https://doi.org/10.1088/1742-6596/2437/1/012039
Rademacher, L., Beglau, T.H.Y., Heinen, T., Barthel, J. and Janiak, C. (2022) Microwave-Assisted Synthesis of Iridium Oxide and Palladium Nanoparticles Supported on a Nitrogen-Rich Covalent Triazine Framework as Superior Electrocatalysts for the Hydrogen Evolution and Oxygen Reduction Reaction. Frontiers in Chemistry , 10, Article No. 94526. https://doi.org/10.3389/fchem.2022.945261
Putri, S.E., Pratiwi, D.E. and Side, S. (2021) The Effect of Microwave Irradiation on Synthesis of Gold Nanoparticles Using Ethanol Extract of White Bol Guava Leaves. Journal of Physics : Conference Series , 1752, Article ID: 012058. https://doi.org/10.1088/1742-6596/1752/1/012058
Cao, J., Wang, J., Fang, B., Chang, X., Zheng, M. and Wang, H. (2004) Microwave-Assisted Synthesis of Flower-Like ZnO Nanosheet Aggregates in a Room-Temperature Ionic Liquid. Chemistry Letters , 33, 1332-1333. https://doi.org/10.1246/cl.2004.1332
Cao, Y., Liu, B., Huang, R., Xia, Z. and Ge, S. (2011) Flash Synthesis of Flower-Like ZnO Nanostructures by Microwave-Induced Combustion Process. Materials Le t ters , 65, 160-163. https://doi.org/10.1016/j.matlet.2010.09.072
Li, X., Wang, C., Zhou, X., Liu, J., Sun, P. and Lu, G. (2014) Gas Sensing Properties of Flower-Like ZnO Prepared by a Microwave-Assisted Technique. RSC Advances , 4, 47319-47324. https://doi.org/10.1039/c4ra07425d
Hasanpoor, M., Aliofkhazraei, M. and Delavari, H. (2015) Microwave-Assisted Synthesis of Zinc Oxide Nanoparticles. Procedia Materials Science , 11, 320-325. https://doi.org/10.1016/j.mspro.2015.11.101
Krishnapriya, R., Praneetha, S. and Murugan, A.V. (2016) Investigation of the Effect of Reaction Parameters on the Microwave-Assisted Hydrothermal Synthesis of Hierarchical Jasmine-Flower-Like ZnO Nanostructures for Dye-Sensitized Solar Cells. New Journal of Chemistry , 40, 5080-5089. https://doi.org/10.1039/c6nj00457a
Wojnarowicz, J., Opalinska, A., Chudoba, T., Gierlotka, S., Mukhovskyi, R., Pietrzykowska, E., et al . (2016) Effect of Water Content in Ethylene Glycol Solvent on the Size of ZnO Nanoparticles Prepared Using Microwave Solvothermal Synthesis. Journal of Nanomaterials , 2016, Article ID: 2789871. https://doi.org/10.1155/2016/2789871
Wojnarowicz, J., Chudoba, T., Gierlotka, S., Sobczak, K. and Lojkowski, W. (2018) Size Control of Cobalt-Doped ZnO Nanoparticles Obtained in Microwave Solvothermal Synthesis. Crystals , 8, Article No. 179.
Liu, H., Liu, H., Yang, J., Zhai, H., Liu, X. and Jia, H. (2019) Microwave-Assisted One-Pot Synthesis of Ag Decorated Flower-Like ZnO Composites Photocatalysts for Dye Degradation and NO Removal. Ceramics International , 45, 20133-20140. https://doi.org/10.1016/j.ceramint.2019.06.279
1] Aljaafari, A., Ahmed, F., Awada, C. and Shaalan, N.M. (2020) Flower-Like ZnO Nanorods Synthesized by Microwave-Assisted One-Pot Method for Detecting Reducing Gases: Structural Properties and Sensing Reversibility. Frontiers in Chem i stry , 8, Article No. 456. https://doi.org/10.3389/fchem.2020.00456
Rini, A.S., Rati, Y. and Maisita, S.W. (2021) Of ZnO Nanoparticle Using Sandoricum Koetjape Peel Extract as Bio-Stabilizer under Microwave Irradiation. Journal of Physics : Conference Series , 2049, Article ID: 012069. https://doi.org/10.1088/1742-6596/2049/1/012069
Sulistyo Rini, A., Aji, A.P. and Rati, Y. (2022) Microwave-Assisted Biosynthesis of Flower-Shaped ZnO for Photocatalyst in 4-Nitrophenol Degradation. Communic a tions in Science and Technology , 7, 135-139. https://doi.org/10.21924/cst.7.2.2022.937
Elazab, H.A., Moussa, S., Gupton, B.F. and El-Shall, M.S. (2014) Microwave-Assisted Synthesis of Pd Nanoparticles Supported on Fe 3 O 4 , Co 3 O 4 , and Ni(OH) 2 Nanoplates and Catalysis Application for CO Oxidation. Journal of N a noparticle Research , 16, Article ID: 2477. https://doi.org/10.1007/s11051-014-2477-0
Elazab, H.A., Sadek, M.A. and El-Idreesy, T.T. (2018) Microwave-Assisted Synthesis of Palladium Nanoparticles Supported on Copper Oxide in Aqueous Medium as an Efficient Catalyst for Suzuki Cross-Coupling Reaction. Adsorption Science & Technology , 36, 1352-1365. https://doi.org/10.1177/0263617418771777
Chen, J., Wang, J., Zhang, X. and Jin, Y. (2008) Microwave-Assisted Green Synthesis of Silver Nanoparticles by Carboxymethyl Cellulose Sodium and Silver Nitrate. Materials Chemistry and Physics , 108, 421-424.
Blosi, M., Albonetti, S., Gatti, F., Dondi, M., Migliori, A., Ortolani, L., Morandi, V. and Baldi, G. (2010) Au, Ag and Au-Ag Nanoparticles: Microwave-Assisted Synthesis in Water and Applications in Ceramic and Catalysis. Nanotech , 1, 352-355.
Wang, B., Zhuang, X., Deng, W. and Cheng, B. (2010) Microwave-Assisted Synthesis of Silver Nanoparticles in Alkalic Carboxymethyl Chitosan Solution. Enginee r ing , 2, 387-390.
Saha, S., Malik, M.M. and Qureshi, M.S. (2013) Microwave Synthesis of Silver Nanoparticles. Nano Hybrids , 4, 99-112. https://doi.org/10.4028/www.scientific.net/nh.4.99
Iqbal, N., Abdul Kadir, M.R., Nik Malek, N.A.N., Mahmood, N.H.B., Murali, M.R. and Kamarul, T. (2013) Characterization and Antibacterial Properties of Stable Silver Substituted Hydroxyapatite Nanoparticles Synthesized through Surfactant Assisted Microwave Process. Materials Research Bulletin , 48, 3172-3177. https://doi.org/10.1016/j.materresbull.2013.04.068
Pal, J., Deb, M.K. and Deshmukh, D.K. (2013) Microwave-Assisted Synthesis of Silver Nanoparticles Using Benzo-18-Crown-6 as Reducing and Stabilizing Agent. Applied Nanoscience , 4, 507-510. https://doi.org/10.1007/s13204-013-0229-6
Rai, P., Majhi, S.M., Yu, Y. and Lee, J. (2015) Synthesis of Plasmonic Ag@SnO 2 Core-Shell Nanoreactors for Xylene Detection. RSC Advances , 5, 17653-17659. https://doi.org/10.1039/c4ra13971b
Karimipour, M., Mollaei, M., Shabani, E., Molaei, M., Ashrafi, J. and Saghatoleslami, N. (2015) Microwave Synthesis of Oleylamine-Capped Ag Nanoparticles in Aqueous Solution. Materials Science , 21, 182-186. https://doi.org/10.5755/j01.ms.21.2.6480
Ebrahimi, M., Zakery, A., Karimipour, M. and Molaei, M. (2016) Nonlinear Optical Properties and Optical Limiting Measurements of Graphene Oxide-Ag@TiO 2 Compounds. Optical Materials , 57, 146-152. https://doi.org/10.1016/j.optmat.2016.04.039
Karimipour, M., Mostoufirad, S., Molaei, M., Nikabadi, H.R. and Nesheli, A.G. (2016) Free Reducing Agent, One Pot, and Two Steps Synthesis of Ag@SiO 2 Core-Shells Using Microwave Irradiation. Journal of Nano - and Electronic Physics , 8, Article No. 03020. https://doi.org/10.21272/jnep.8(3).03020
Miglietta, M.L., Alfano, B., Polichetti, T., Massera, E., Schiattarella, C. and Francia, G.D. (2018) Effective Tuning of Silver Decorated Graphene Sensing Properties by Adjusting the Ag NPs Coverage Density. Sensors : Proceedings of the Third National Conference on Sensors , Rome, 23-25 February 2016.
Jyothi, D., Cherriyan, S.P., Ahmed, S.R.R., Priya, S., et al . (2020) Microwave Assisted Green Synthesis of Silver Nanoparticles Using Coleus Amboinicus Leaf Extract. International Journal of Applied Pharmaceutics , 12, 56-61.
Ahmed, F., AlOmar, S.Y., Albalawi, F., Arshi, N., Dwivedi, S., Kumar, S., et al . (2021) Microwave Mediated Fast Synthesis of Silver Nanoparticles and Investigation of Their Antibacterial Activities for Gram-Positive and Gram-Negative Microorganisms. Crystals , 11, Article No. 666. https://doi.org/10.3390/cryst11060666
Li, D. and Komarneni, S. (2006) Synthesis of Pt Nanoparticles and Nanorods by Microwave-Assisted Solvothermal Technique. Zeitschrift fuer Naturforschung B , 61, 1566-1572.
Kundu, P., Nethravathi, C., Deshpande, P.A., Rajamathi, M., Madras, G. and Ravishankar, N. (2011) Ultrafast Microwave-Assisted Route to Surfactant-Free Ultrafine Pt Nanoparticles on Graphene: Synergistic Co-Reduction Mechanism and High Catalytic Activity. Chemistry of Materials , 23, 2772-2780. https://doi.org/10.1021/cm200329a
Pal, J., Deb, M.K., Deshmukh, D.K. and Sen, B.K. (2014) Microwave-Assisted Synthesis of Platinum Nanoparticles and Their Catalytic Degradation of Methyl Violet in Aqueous Solution. Applied Nanoscience , 4, 61-65.
Wojnicki, M., Luty-Błocho, M., Kwolek, P., Gajewska, M., Socha, R.P., Pędzich, Z., et al . (2021) The Influence of Dielectric Permittivity of Water on the Shape of Ptnps Synthesized in High-Pressure High-Temperature Microwave Reactor. Scientific Reports , 11, Article No. 4851. https://doi.org/10.1038/s41598-021-84388-2
Liu, F.K., Huang, P.W., Chang, Y.C., Ko, C.J., Ko, F.H. and Chu, T.C. (2005) Formation of Silver Nanorods by Microwave Heating in the Presence of Gold Seeds. Journal of Crystal Growth , 273, 439-445.
Mallikarjuna, N.N. and Varma, R.S. (2017) Microwave-Assisted Shape-Controlled Bulk Synthesis of Noble Nanocrystals and Their Catalytic Properties. Crystal Growth & Design , 8, 291-295.
Yasmin, A., Ramesh, K. and Rajeshkumar, S. (2014) Optimization and Stabilization of Gold Nanoparticles by Using Herbal Plant Extract with Microwave Heating. N a no Convergence , 1, 12.
Bhosale, M.A., Chenna, D.R., Ahire, J.P. and Bhanage, B.M. (2015) Morphological Study of Microwave-Assisted Facile Synthesis of Gold Nanoflowers/Nanoparticles in Aqueous Medium and Their Catalytic Application for Reduction of p-Nitrophenol to p-Aminophenol. Royal Society of Chemistry Advances , 5, 52817-52823.
Ngo, V.K.T., Nguyen, H.P.U., Huynh, T.P., Tran, N.N.P., Lam, Q.V. and Huynh, T.D. (2015) Preparation of Gold Nanoparticles by Microwave Heating and Application of Spectroscopy to Study Conjugate of Gold Nanoparticles with Antibody E . coli O157:H7. Advances in Natural Sciences : Nanoscience and Nanotechnology , 6, Article ID: 035015. https://doi.org/10.1088/2043-6262/6/3/035015
Bayazit, M.K., Yue, J., Cao, E., Gavriilidis, A. and Tang, J. (2016) Controllable Synthesis of Gold Nanoparticles in Aqueous Solution by Microwave Assisted Flow Chemistry. ACS Sustainable Chemistry & Engineering , 4, 6435-6442. https://doi.org/10.1021/acssuschemeng.6b01149
Shah, K.W. and Zheng, L. (2019) Microwave-Assisted Synthesis of Hexagonal Gold Nanoparticles Reduced by Organosilane (3-Mercaptopropyl)trimethoxysilane. M a terials , 12, Article No. 1680. https://doi.org/10.3390/ma12101680
Marinoiu, A., Andrei, R., Vagner, I., Niculescu, V., Bucra, F., Constantinescu, M. and Carcadea, E. (2020) One Step Synthesis of Au Nanoparticles Supported on Graphene Oxide Using an “Eco-Friendly” Microwave-Assisted Process. Materials Science , 26, 249-254.
Ngo, V.K.T., Nguyen, D.G., Huynh, T.P. and Lam, Q.V. (2016) A Low Cost Technique for Synthesis of Gold Nanoparticles Using Microwave Heating and Its Application in Signal Amplification for Detecting Escherichia coli O157:H7 Bacteria. Advances in Natural Sciences : Nanoscience and Nanotechnology , 7, Article ID: 035016. https://doi.org/10.1088/2043-6262/7/3/035016
Liu, S., Maljovec, D., Wang, B., Bremer, P.T. and Pascucci, V. (2017) Visualizing High-Dimensional Data: Advances in the Past Decade. IEEE Transaction on Visu a lization and Computer Graphs , 23, 21.
Stumpf, M.P.H. and Porter, M.A. (2012) Critical Truths about Power Laws. Science , 335, 665-666. https://doi.org/10.1126/science.1216142