Since Thomas John Baker, a German scientist, discovered Seebeck effect in 1821, scientists constantly searched for thermoelectric (TE) materials for energy application. Some researchers discovered inorganic TE materials, such as Bi
2Te
3 and SnSe, with good TE properties and extensive application in energy field [
1–
4]. In comparison with inorganic TE materials, development of organic TE materials is retarded by poor stability of their properties, such as high temperature, that limit their application; processing of organic materials is also difficult compared with inorganic ones. However, organic TE materials and devices feature their own advantages, e.g., abundant resources, low-cost synthesis, mechanical flexibility, and solution processability over large areas [
5–
7]. Currently, increasing number of scientists explore TE properties of organic materials [
8–
13]. On the one hand, electrical conductivity of organic materials can be controlled by methods such as doping, on the other hand, thermal conductivity can be controlled by designing molecular structures [
14–
17]. To increase electrical conductivity, many methods were reproved, for example, using composite materials to fill materials with high electrical conductivity [
18–
20] and preparing new composite structural materials [
21–
24]. These methods only bear significance in controlling P-type TE materials, including poly(3,4-ethylenedioxythiophene) (PEDOT), which show good stability in air [
25,
26]; however, difficulty arises from using these methods to modify TE properties of n-type materials. Recently, some new methods were reported for modification of n-type TE materials, for example, using doping and phase separation method to process large-sized materials [
27] and modifying side chains of molecules; both methods can provide n-type TE materials with good stability in air [
28]. Phenyl-C61-butyric acid methyl ester (PCBM) is one of the promising n-type TE materials, it presents excellent phase segregation characteristic and broad application prospects in field of organic solar cells [
29–
33]. Pure PCBM features high thermal conductivity [
34,
35]; thus, this material cannot be easily processed by the solution method. When used as filler material, PCBM blends with other composites materials and easily results in low thermal conductivity (
k), realizing high electrical conductivity (
s) and high Seebeck coefficient (
S). In some literature [
36–
38] that reported some methods in modifying PCBM, acridine orange base (3,6-bis(dimethylamino) acridine) (AOB) and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzoimidazole (N-DMBI)-doped PCBM resulted in high electrical conductivity, reaching ~4 and ~5.3 S/cm, respectively. However, these materials cannot simultaneously obtain high Seebeck coefficient. Seebeck coefficient of N-DMBI-doped PCBM is smaller than that of AOB-doped PCBM. In this article, we selected AOB and N-DMBI-co-doped PCBM, because it can simultaneously show high electrical conductivity and Seebeck coefficient and good stability by doping in air condition [
39]. For p-type TE materials, we selected modified PEDOT:polystyrene sulfonate (PSS) as p-type leg. Finally, we fabricated p-type and n-type TE modules and tested their output voltage and output power.