With continuing scale down of electronic devices, increasing influence of the surface and interactions with the surrounding environment are inevitable and often present a major challenge. From device performance limits to thermal management, understanding how such extrinsic factors affect fundamental processes such as charging, electron-phonon coupling and energy relaxation/dissipation is fundamentally important. Due to their atomic thickness, carbon nanotubes and graphene are interesting platforms to examine how local chemical environments affect these fundamental processes. Such studies, in turn, may provide effective means of controlling device characteristics. Our efforts in this area include synthesis and device fabrication to elucidating important characteristics of carbon nanotubes and graphene such as local chemical environment induced changes in charge carrier density and how such effects complicate experiments quantifying basic properties such as electron-phonon coupling and phonon lifetimes. Carrier density and electron-phonon coupling are two of the most fundamentally important characteristics for any electronics applications. Understanding of intrinsic and extrinsic factors that alter these characteristics are being exploited to advance various applications including solar energy conversion, transparent conductors for displays, and novel memories and switches for next-generation computing.