Fullerenes, higher fullerenes, and their hybrids: Synthesis, characterization, and environmental considerations

The search for alternative and renewable energy sources has become one of the major thrusts of the twenty‐first‐century researchers due to the increasing demand for energy. Innovations and development of photovoltaics, dye‐sensitized or polymer solar cells, high‐efficiency lithium ion batteries, supercapacitors, trans­ parent conductors, hydrogen productions and storage systems, microbial fuel cells, catalyst‐driven proton exchange membrane fuel cells, thermoelectric power gener­ ation, etc., have come to the forefront in alternative energy research [80, 149]. In quest of effective energy transfer, distribution, and storage, improved materials are being synthesized since the 1990s. Nanoscale manipulation of materials has fueled such development [11]. Improved surface area at the nanoscale and targeted molec­ ular placement or alteration in nanomaterials resulted in desired band gap tuning and effective electron transfer, storage, and surface activity [111]. One of the key challenges that eluded energy researchers for decades was an efficient photoelec­ tron acceptor with high structural stability and chemical reactivity; a spheroidal