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Suggs, Kelvin

Publications and source records attributed to Suggs, Kelvin.

Doubly-Charged Negative Ions as Novel Tunable Catalysts: Graphene and Fullerene Molecules Versus Atomic Metals

The fundamental mechanism underlying negative-ion catalysis involves bond-strength breaking in the transition state (TS). Doubly-charged atomic/molecular anions are proposed as novel dynamic tunable catalysts, as demonstrated in water oxidation into peroxide. Density Functional Theory TS calculations have found a tunable energy activation barrier reduction ranging from 0.030 eV to 2.070 eV, with Si 2– , Pu 2– , Pa 2– and Sn 2– being the best catalysts; the radioactive elements usher in new application opportunities. C 60 2– significantly reduces the standard C 60 – TS energy barrier, while graphene increases it, behaving like cationic systems. According to their reaction barrier reduction efficiency, variation across charge states and systems, rank-ordered catalysts reveal their tunable and wide applications, ranging from water purification to biocompatible antiviral and antibacterial sanitation systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Fullerene Negative Ions: Formation and Catalysis

We first explore negative-ion formation in fullerenes C 44 to C 136 through low-energy electron elastic scattering total cross sections calculations using our Regge-pole methodology. Then, the formed negative ions C 44 – to C 136 – are used to investigate the catalysis of water oxidation to peroxide and water synthesis from H 2 and O 2 . The exploited fundamental mechanism underlying negative-ion catalysis involves hydrogen bond strength-weakening/breaking in the transition state. Density Functional Theory transition state calculations found C 60 – optimal for both water and peroxide synthesis, C 100 – increases the energy barrier the most, and C 136 – the most effective catalyst in both water synthesis and oxidation to H 2 O 2 .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗