Growing attention to the development of sustainable solar-to-energy conversion applications has resulted in the synthesis of promising and environment-friendly nanomaterials as energy harvesters. Among various carbon nanomaterials, carbon dots (CDs) have received significant attention due to their excellent light absorption capability, broad absorption region, and superior photostability with enormous potential for solar energy applications. Therefore, utilizing and modulating the charge carriers generated from CDs is critical for achieving a high energy conversion efficiency of CDs. Herein, we focus on the distinct characteristics of CDs as energy converters from charge excitation to charge separation and transfer for various solar-to-energy applications, including photovoltaic cells, photocatalysts, and photoelectrocatalysts. We anticipate that this review will offer insight into the synthesis and design of novel nanocomposites with a fundamental analysis of the photochemical properties and future development of energy conversion devices. K E Y W O R D Scarbon dots, charge carrier, energy conversion, photocatalyst, photoelectrocatalyst | INTRODUCTIONCarbon dots (CDs) have received widespread attention in the scientific community as one of the latest additions to carbon-based nanomaterials. CDs, which are typically defined as quasi-spherical carbon nanoparticles of <10 nm, exhibit unique physical, chemical, and optical properties, including high light absorption, tunable photoluminescence, and excellent electron donor/acceptor characteristics. [1][2][3][4][5][6] Owing to these advantages, CDs can be applied in bioimaging, 7,8 biosensing, 9-11 drug delivery, [12][13][14][15] phototherapy, [16][17][18] and light-harvesting applications in energy transducers. [19][20][21] Moreover, the facile and mild synthetic nature of CDs using various combinations of carbon precursors and other molecular agents can provide easy access to the formation of sp 2 -hybridized carbonaceous core of CDs, with an amorphous shell rich in surface functional groups containing oxygen and nitrogen. These surface functional moieties can be potentially functionalized with other organic molecules on the CD surface, allowing the control of photoluminescence (PL)

Even though many graphene derivatives that are atomically thin two-dimensional structures, such as graphene oxide (GO), have triggered enormous interest in the scientific and industrial communities owing to their easy...

As the demand for next-generation electronics is increasing, organic and polymer-based semiconductors are in the spotlight as suitable materials owing to their tailorable structures along with flexible properties. Especially, polyimide...