Heteroatom-doped carbon materials have received great attention for applications in electrode materials. However, conventional heteroatom-doping methods sacrifice conductivity, stability, and specific surface area (SSA). Here, the carbon quantum dots (CDs) are used as carriers of N, P, O to form electron-rich regions promoting electron transport without decreasing stability and SSA. The CDs promote the formation of graphitic nitrogen in the composite, which effectively reduces their internal resistance by increasing the dielectric constant. Moreover, the orderly growth of ice crystals generates a unique bridged layer structure under bidirectional freeze-casting in a mixture of GO/CDs/microfibrillated cellulose, which gives the composite super-compressibility. Notably, the optimal sample has a 117% increase in specific capacitance. The CDs also improve wettability and thus reduce the charge transfer resistance giving a large desalination capacity of 32.59 mg g⁻¹ (504 mg L⁻¹ NaCl). This work illustrates the unique role of CDs in improving the electrochemical performance of composites.

杂原子掺杂碳材料在电极材料中的应用引起了极大的关注。然而，常规的杂原子掺杂方法牺牲了电导率，稳定性和比表面积（SSA）。此处，碳量子点（CD）用作N，P，O的载流子，形成富电子区域，促进电子传输，而不会降低稳定性和SSA。CD促进了复合材料中石墨氮的形成，从而通过增加介电常数有效降低了其内部电阻。此外，冰晶的有序生长在GO / CD /微纤化纤维素的混合物的双向冷冻浇铸下产生了独特的桥接层结构，从而赋予了复合材料超压缩性。值得注意的是，最佳样品的比电容增加了117％。^-1（504 mg L ^-1 NaCl）。这项工作说明了CD在改善复合材料电化学性能方面的独特作用。