1:00 PM - 1:15 PM
▼ [14p-303-1] The Solution to Cost and Stability in Perovskite Solar Cells by All-Carbon Approach
Keywords:Perovskite solar cells, Carbon nanotubes, Stability
Since Miyasaka and colleagues adopted perovskite semiconductors into photovoltaic devices, perovskite solar cells (PSCs) have received much attention in recent years, on account of high power conversion efficiency (PCE) and solution-processability. Their reported PCEs have soared rapidly in the last five years, and now some of the certified efficiencies exceed 20%. However, there remains several shortcomings, namely high-cost and stability that need to be addressed. Numerous research groups around the world have been working on these issues.
One of the promising methods, which can resolve both the issues, is using carbon nanotube (CNT) materials. CNTs have shown to be effective in replacing metal electrodes and enhancing the stability of PSCs in air. Li et al., and Aitola et al., used aerosol-produced single-walled CNTs as top electrodes to replace expensive metals and hole-conductors, but their PCEs and stability fell short due to high severe hysteresis. Also, Snaith and colleagues, and Matsuda and colleagues demonstrated hydrophobic nature of CNTs can function as an effective passivation. Nevertheless, they still rely on an expensive gold electrode, and high-temperature annealed TiO2, which translate to high-cost and high hysteresis, respectively.
Here, we report PSCs in which lead perovskite layer is sandwiched by C60 and single-walled CNTs to maximize stability. Room temperature, air-processed PSCs with a configuration of indium tin oxide (ITO)/C60/CH3NH3PbI3/CNT produced a PCE of 13% with excellent stability and no hysteresis. Upon addition of 2,2’,7,7’-tetrakis(N,N-di-p-methoxyphenylamino)-9,9’-spirobifluorene, PCE increased to 17%, which is comparable to the metal-based reference devices (18%). Furthermore, we redefined the mechanism of degradation in terms of water and trapped charge theory. P3HT-applied devices lasted more than 1000 hours after the encapsulation under illuminatin in ambence.
One of the promising methods, which can resolve both the issues, is using carbon nanotube (CNT) materials. CNTs have shown to be effective in replacing metal electrodes and enhancing the stability of PSCs in air. Li et al., and Aitola et al., used aerosol-produced single-walled CNTs as top electrodes to replace expensive metals and hole-conductors, but their PCEs and stability fell short due to high severe hysteresis. Also, Snaith and colleagues, and Matsuda and colleagues demonstrated hydrophobic nature of CNTs can function as an effective passivation. Nevertheless, they still rely on an expensive gold electrode, and high-temperature annealed TiO2, which translate to high-cost and high hysteresis, respectively.
Here, we report PSCs in which lead perovskite layer is sandwiched by C60 and single-walled CNTs to maximize stability. Room temperature, air-processed PSCs with a configuration of indium tin oxide (ITO)/C60/CH3NH3PbI3/CNT produced a PCE of 13% with excellent stability and no hysteresis. Upon addition of 2,2’,7,7’-tetrakis(N,N-di-p-methoxyphenylamino)-9,9’-spirobifluorene, PCE increased to 17%, which is comparable to the metal-based reference devices (18%). Furthermore, we redefined the mechanism of degradation in terms of water and trapped charge theory. P3HT-applied devices lasted more than 1000 hours after the encapsulation under illuminatin in ambence.