Carbon dots (CDs) are carbon-based nanomaterials with advantageous luminescent properties, making them promising alternatives to other molecular and nanosized fluorophores. However, the development of CDs is impaired by the low synthesis yield of standard fabrication strategies, making high-yield strategies essential. To help future studies to focus on cleaner production strategies, we have employed a Life Cycle Assessment (LCA) to compare and understand the environmental impacts of available routes for the high-yield synthesis of carbon dots. These routes were: (1) production of hydrochar, via hydrothermal treatment of carbon precursors, and its alkaline-peroxide treatment into high-yield carbon dots; (2) thermal treatment of carbon precursors mixed in a eutectic mixture of salts. Results show that the first synthesis route is associated with the lowest environmental impacts. This is attributed to the absence of the mixture of salts in the first synthesis route, which offsets its higher electricity consumption. Sensitivity analysis showed that the most critical parameter in the different synthetic strategies is the identity of the carbon precursor, with electricity being also relevant for the first synthesis route. Nevertheless, the use of some carbon precursors (as citric acid) with higher associated environmental impacts may be justified by their beneficial role in increasing the luminescent performance of carbon dots. Thus, the first synthesis route is indicated to be the most environmental benign and should be used as a basis in future studies aimed to the cleaner and high-yield production of carbon dots.

碳点 (CD) 是碳基纳米材料，具有优越的发光特性，使其成为其他分子和纳米尺寸荧光团的有希望的替代品。然而，标准制造策略的低合成产率损害了 CD 的发展，因此高产率策略必不可少。为了帮助未来的研究专注于清洁生产战略，我们采用了生命周期评估 (LCA) 来比较和了解碳点高产合成的可用路线对环境的影响。这些路线是：（1）水炭的生产，通过碳前体的水热处理，并将其碱性过氧化物处理成高产碳点；(2) 对混合在盐的低共熔混合物中的碳前体进行热处理。结果表明，第一种合成路线对环境的影响最小。这归因于第一个合成路线中没有盐的混合物，这抵消了其较高的电力消耗。敏感性分析表明，不同合成策略中最关键的参数是碳前体的特性，电也与第一个合成路线有关。尽管如此，使用一些具有更高相关环境影响的碳前体（如柠檬酸）可能是因为它们在提高碳点发光性能方面的有益作用是合理的。因此，第一种合成路线被认为是最环保的，应作为未来研究的基础，旨在实现更清洁和高产的碳点生产。