超级电容器作为一种电化学储能器件，因其具有体积小、功率密度高、充电速度快、循环寿命长等优点，在各个领域受到了广泛关注和应用。为了满足超级电容器高能量密度及长循环寿命的需求，开发具有高比容量、低内阻、长循环稳定性的电极材料至关重要。具有比表面积大、电导率高、稳定性好以及孔径分布广等优点的多孔炭被认为是应用前景最广阔的电极材料。渣油成本低廉，且具有高碳含量，以渣油为碳源制备高性能、低成本的多孔炭对于推动超级电容器的发展具有非常重要的意义。

本文以渣油为碳源，通过溶剂热和高温炭化活化策略制备得到了一系列多孔炭微球材料，并进一步通过掺杂改性得到了氮掺杂多孔炭材料。探究了预交联参数、炭化温度、尿素比例和活化剂对多孔炭的孔结构及电化学性能的影响规律，优化了多孔电容炭材料的制备工艺。主要研究内容及结果如下：

（1）以纯化脱灰的渣油为碳源，KOH为活化剂，通过溶剂热处理和高温炭化活化相结合的方法，制备得到多孔炭微球（RPCs）材料。氯仿用量为19 mL，炭化温度为800 ℃时，RPC-800具有高的比表面积2561 m²·g^-1。在6M的KOH电解液中，RPC-800在0.5 A·g^-1下具有385 F·g^-1的高比电容；以RPC-800组装成对称超级电容器，在195.3 W·kg^-1的功率密度下显示出10.47 Wh·kg^-1的高能量密度，5 A·g^-1下循环10000次后，电容保持率为96.9%。

（2）以炭微球前驱体（CMP）为碳源，尿素为氮源，KOH活化制得氮掺杂多孔炭（NPCs）材料。所制备的炭材料具有以下特点：（i）蜂窝状的孔道结构缩小了电解质离子的扩散阻力以及电子和离子的输运路径；（ii）NPC-3的高表面积（2653 m²·g^-1）以及分布良好的微孔/介孔，为电荷离子储存提供了足够的电活性位点；（iii）在碳骨架中引入氮原子不仅提高了炭材料的润湿性和导电性，还提供了额外的赝电容。在这些优势的多重协同作用下，NPC-3在6M的KOH电解液中转移扩散电阻较低（0.67 Ω），0.5 A·g^-1下比电容为322 F·g^-1；以NPC-3组装成对称超级电容器，在5 A·g^-1下循环10000次，比电容仍能保持100.2%，在125 W·kg^-1的功率密度下，能量密度为9.62 Wh·kg^-1。

Supercapacitors, as an electrochemical energy storage device, have received widespread attention and application in various fields due to their have the advantages of small volume, high power density, fast charging speed, and long circulation life. To address the demand for high energy density and long cycle life of supercapacitors, the development of electrode materials with high specific capacity, low internal resistance and extended cycle stability is essential. Porous carbon materials possessing large specific surface area, high electrical conductivity, good stability and wide pore size distribution are considered to be the most promising electrode materials. Residual oil is low cost and has a high carbon content. The preparation of high-performance and low-cost porous carbon materials using residual oil as carbon source is of great importance to promote the development of supercapacitors.

In this thesis, a series of porous carbon microspheres were prepared and obtained by solvent heat and high temperature carbonization activation strategy using residual oil as carbon source, which were further modified by doping to obtain nitrogen doped porous carbon materials. The effects of pre-crosslinking parameters, charring temperature, urea ratio and activator on the pore structure and electrochemical properties of porous carbon were investigated, and the preparation process of porous capacitive carbon materials was optimized. The main research and results are as follows:

(1) Purified de-ashed residual oil as the carbon source, KOH as the activator, the porous carbon (RPCs) materials were prepared by a combination of solvent heat treatment and high-temperature carbonization. RPC-800, synthesized at a carbonization temperature of 800 °C and a chloroform dosage of 19 mL, displayed a high specific surface area of 2561 m²·g^-1. RPC-800 has a high specific capacitance of 385 F·g^-1 at 0.5 A·g^-1 in 6 M KOH electrolyte. The as-assembled symmetrical supercapacitor also has a high energy density of 10.47 Wh·kg^-1 at a power density of 195.3 W·kg^-1, and a capacitance retention rate of 96.9% after 10,000 cycles at 5 A·g^-1.

(2) Carbon microsphere precursors (CMP) as the carbon source, urea as the nitrogen source, and KOH as the activator, the nitrogen-doped porous carbon (NPCs) materials were prepared. The obtained carbon material has the following characteristics: (i) The honeycomb pore structure narrows the diffusion resistance of electrolyte ions and the transport paths of electrons and ions; (ii) The high surface area (2653 m²·g^-1) and well-distributed micropores/mesopores of NPC-3 provide sufficient electroactive sites for charge ion storage; (iii) The introduction of nitrogen atoms in the carbon skeleton not only improves the moisture and conductivity of the carbon material, but also provides additional capacitor. Resulting from the multiple synergistic effects of these advantages, NPC-3 has low transfer diffusion resistance (0.67 Ω) in 6 M KOH electrolyte and specific capacitance of 322 F·g^-1 at 0.5 A·g^-1; assembled as symmetrical supercapacitor, NPC-3 exhibits specific capacitance remains 100.2% after 10,000 cycles at 5 A·g^-1, and high energy density of 9.62 Wh·kg^-1 at power density of 125 W·kg^-1.

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