To make quantum dot sensitized solar cells (QDSCs) competitive, a power conversion efficiency (PCE) comparable to other developing solar cells is required. Significant attention has been paid to undoped or nitrogen (N) doped carbon quantum dots (N-CQDs) for use as sensitizers or light harvesters in solar cells. However, to our knowledge, the nitrogen and sulfur (S) co-doped CQDs (N, S-CQDs) have never been used as the absorbing layer alone. In the present work, we synthesize nitrogen and sulfur co-doped carbon quantum dots (N, S-CQDs) from a single precursor thioacetamide (TA), via a hydrothermal method. The as-prepared N, S-CQDs were employed as a “green” photoactive layer in TiO₂ film, as photoanode. The solar cell delivered an open-circuit voltage (V_oc) of 0.43 V, short-circuit current (J_sc) of 0.61 mA/cm⁻², fill factor (FF) of 52 %, and PCE of 1.36%; highest among all the carbon-based QDSCs. Moreover, Device-NS showed more stability over 48 h compared to Device-C and Device-N. Undeniably, the achieved PCE is not satisfactory; however, the upgraded device fabrication and structural design may improve PCE and current densities while sustaining the high open-circuit voltage. This study demonstrated the potential application of N, S-CQDs for low-cost, “green” quantum dot solar cell applications.

为了使量子点敏化太阳能电池 (QDSC) 具有竞争力，需要具有与其他开发中的太阳能电池相当的功率转换效率 (PCE)。未掺杂或氮 (N) 掺杂的碳量子点 (N-CQD) 用作太阳能电池中的敏化剂或光收集器受到了极大的关注。然而，据我们所知，氮和硫 (S) 共掺杂的 CQDs (N, S-CQDs) 从未单独用作吸收层。在目前的工作中，我们通过水热法从单一前体硫代乙酰胺 (TA) 合成氮和硫共掺杂的碳量子点 (N, S-CQDs)。所制备的 N, S-CQD 用作 TiO ₂薄膜中的“绿色”光敏层，作为光阳极。太阳能电池提供开路电压(V _oc )0.43 V，短路电流(J _sc ) 0.61 mA/cm ^-2，填充因子 (FF) 52%，PCE 1.36%；在所有碳基 QDSC 中最高。此外，与 Device-C 和 Device-N 相比，Device-NS 在 48 小时内表现出更高的稳定性。不可否认，实现的PCE并不令人满意；然而，升级后的器件制造和结构设计可能会在维持高开路电压的同时提高PCE和电流密度。这项研究证明了 N, S-CQD 在低成本、“绿色”量子点太阳能电池应用中的潜在应用。