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Single-walled carbon nanotube (SWCNT)-based thermoelectric materials have been extensively studied in the field of flexible wearable devices due to their high flexibility and excellent electrical conductivity (σ). However, poor Seebeck coefficient ( S ) and high thermal conductivity limit their thermoelectric application. In this work, free-standing MoS 2 /SWCNT composite films with improved thermoelectric performance were fabricated by doping SWCNTs with MoS 2 nanosheets. The results demonstrated that the energy filtering effect at the MoS 2 /SWCNT interface increased the S of composites. In addition, the σ of composites was also improved due to the reason that S -π interaction between MoS 2 and SWCNTs made good contact between MoS 2 and SWCNTs and improved carrier transport. Finally, the obtained MoS 2 /SWCNT showed a maximum power factor of 131.9 ± 4.5 μW m -1 K -2 at room temperature with a σ of 680 ± 6.7 S cm -1 and an S of 44.0 ± 1.7 μV K -1 at a MoS 2 /SWCNT mass ratio of 15:100. As a demonstration, a thermoelectric device composed of three pairs of p-n junctions was prepared, which exhibited a maximum output power of 0.43 μW at a temperature gradient of 50 K. Therefore, this work offers a simple method of enhancing the thermoelectric properties of SWCNT-based materials.

The chemical percolation devolatilization (CPD) model can simulate the formation of various products during the coal pyrolysis process and predict the products composition relatively accurately. In this study, the pyrolysis products of a typical low-rank coal were calculated using the CPD model, and several model improvements were proposed by combining the experimental results in a lab-scale pyrolysis system. The chemical structural parameters calculated from the Genetti correlations were verified by adjusting the initial fraction of char bridges ( c 0 ) from 0.098 to 0.25. A yield difference (Δ f tar ) was defined in this paper to analyze the consumption of tar fragments in the model, and it was found that the deviations between experiments and calculations resulted from the weak influence of crosslinking. A modification expression was adopted to amplify the tar consumption: , which improved the accuracy of the model on the tar yield with errors of less than ±0.5 wt%. Furthermore, this paper also developed a correlation in an exponential form about gas composition, which attempted to extend the application of the CPD coalification reference mesh for the coal away from interpolation triangles. The improved model by the correlation predicted CH 4 , CO, and CO 2 yields for this typical low-rank coal accurately in most cases. Compared with the original CPD model, the modified model showed better agreement with the experimental results and predicted 71.4% and 88.6% of the data points in this work within ±10% and ±20% errors, respectively., Competing Interests: The authors declare that there are no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

Amine emissions from a post-combustion CO 2 capture process can lead to solvent loss and serious environmental issues. The emission characteristics of amine mixtures and influencing factors are seldom reported. This work comprehensively investigated emissions of AMP (2-amino-2-methyl-1-propanol)/MEA (monoethanolamine) from a 3.6 Nm 3 /h flue gas CO 2 capture platform. The condensation nuclei in flue gas dominated the generation of amine aerosols and resulted in a heavy total amine loss of over 1400 mg/Nm 3 , which is equivalent to 5.88 kg/t CO 2 captured under the high nuclei concentration scenario. Inside the absorber, a higher CO 2 concentration and lower lean solvent CO 2 loading can significantly promote the growth of aerosols due to the intensive reaction of CO 2 absorption. The maximum amine emissions were observed at 8-12 vol % CO 2 . The flue gas temperature and liquid/gas ratio had insignificant effects on aerosol emissions, while amine emissions after the absorber increased 340-500% as the lean solvent temperature increased from 30 to 50 °C. A synergistic control strategy of nuclei pretreatment, operating optimization, and water scrubbing can effectively reduce amine emissions to 4.0 mg/Nm 3 MEA and 8.3 mg/Nm 3 AMP.