Controlled Fabrication of PbS Quantum‐Dot/Carbon‐Nanotube Nanoarchitecture and its Significant Contribution to Near‐Infrared Photon‐to‐Current Conversion
Controlled Fabrication of PbS Quantum‐Dot/Carbon‐Nanotube Nanoarchitecture and its Significant Contribution to Near‐Infrared Photon‐to‐Current Conversion
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DOI：
10.1002/adfm.201100824
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发表时间：
2011-11
影响因子：
19
通讯作者：
Defa Wang;Jayanta K. Baral;Haiguang Zhao;B. Gonfa;V. Truong;M. A. El Khakani;R. Izquierdo;D. Ma
中科院分区：
文献类型：
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作者：
Defa Wang;Jayanta K. Baral;Haiguang Zhao;B. Gonfa;V. Truong;M. A. El Khakani;R. Izquierdo;D. Ma
通过简单混合预合成的高质量PbS量子点（QD）和油胺（奥拉）预功能化的多壁碳纳米管（MWCNT），合成了基于PbS量子点（QD）和多壁碳纳米管（MWCNT）的溶液加工纳米结构。用奥拉预官能化多壁碳纳米管对于PbS量子点的附着是至关重要的，并且量子点在多壁碳纳米管表面上的覆盖可以通过改变PbS量子点与多壁碳纳米管的比例来调节。表观光致发光（稳态发射和荧光寿命）“淬灭”效应表明从光激发的PbS QD到MWCNT的有效电荷转移。合成的PbS-QD/MWCNT纳米结构进一步结合到空穴传导聚合物聚（3-己基噻吩）-（P3 HT）中，形成P3 HT：PbS-QD/MWCNT纳米杂化物，其中PbS QD充当光收集器，用于吸收太阳光谱的宽波长范围直至近红外（NIR，约1430 nm）范围内的辐射;而一维MWCNT和P3 HT用于分别收集和传输光激发的电子和空穴到阴极和阳极。即使不进行通常所需的“配体交换”以去除长链奥拉配体，所构建的纳米杂化光伏（PV）器件也表现出3.03%的大大增强的功率转换效率（PCE），相比之下，用P3 HT和[6，6]-苯基-C61-丁酸甲酯（PCBM）混合物制成的标准本体异质结PV电池的PCE为2.57%。P3 HT：PbS-QD/MWCNT纳米杂化PV器件的性能改善归因于PbS QD对NIR的显著扩展吸收以及由于集成的MWCNT和P3 HT而有效增强的电荷分离和传输。我们的研究结果表明，适当地整合量子点，多壁碳纳米管，和聚合物到纳米杂化结构是一个有前途的方法，为开发高效的光伏器件。
A solution‐processed nanoarchitecture based on PbS quantum dots (QDs) and multi‐walled carbon nanotubes (MWCNTs) is synthesized by simply mixing the pre‐synthesized high‐quality PbS QDs and oleylamine (OLA) pre‐functionalized MWCNTs. Pre‐functionalization of MWCNTs with OLA is crucial for the attachment of PbS QDs and the coverage of QDs on the surface of MWCNTs can be tuned by varying the ratio of PbS QDs to MWCNTs. The apparent photoluminescence (steady‐state emission and fluorescence lifetime) “quenching” effect indicates efficient charge transfer from photo‐excited PbS QDs to MWCNTs. The as‐synthesized PbS‐QD/MWCNT nanoarchitecture is further incorporated into a hole‐conducting polymer poly(3‐hexylthiophene)‐(P3HT), forming the P3HT:PbS‐QD/MWCNT nanohybrid, in which the PbS QDs act as a light harvester for absorbing irradiation over a wide wavelength range of the solar spectrum up to near infrared (NIR, ≈1430 nm) range; whereas, the one‐dimensional MWCNTs and P3HT are used to collect and transport photoexcited electrons and holes to the cathode and anode, respectively. Even without performing the often required “ligand exchange” to remove the long‐chained OLA ligands, the built nanohybrid photovoltaic (PV) device exhibits a largely enhanced power conversion efficiency (PCE) of 3.03% as compared to 2.57% for the standard bulk hetero‐junction PV cell made with P3HT and [6,6]‐Phenyl‐C61‐Butyric Acid Methyl Ester (PCBM) mixtures. The improved performance of P3HT:PbS‐QD/MWCNT nanohybrid PV device is attributed to the significantly extended absorption up to NIR by PbS QDs as well as the effectively enhanced charge separation and transportation due to the integrated MWCNTs and P3HT. Our research results suggest that properly integrating QDs, MWCNTs, and polymers into nanohybrid structures is a promising approach for the development of highly efficient PV devices.