Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > 2D materials for conducting hole currents from grain boundaries in perovskite solar cells

a,b The structural schematic diagram and energy-level band diagram of a BP-modified PSC with a normal structure. c,d Current density-voltage (J-V) curves (reverse scan) and external quantum efficiency (EQE) spectra of PSCs without (control) and with BP deposition (1~3 times) on perovskite film surface. e Histogram of power conversion efficiencies (PCEs) of PSCs without (control) and with BP modification (BP coating for 2 times). The PCEs are derived from the reverse scans of the J-V curves. f The average PCE enhancement after the modification of perovskite films with different 2-D materials.

CREDIT
by Peng You, Guanqi Tang, Jiupeng Cao, Dong Shen, Tsz-Wai Ng, Zafer Hawash, Naixiang Wang, Chun-Ki Liu, Wei Lu, Qidong Tai, Yabing Qi, Chun-Sing Lee, Feng Yan
a,b The structural schematic diagram and energy-level band diagram of a BP-modified PSC with a normal structure. c,d Current density-voltage (J-V) curves (reverse scan) and external quantum efficiency (EQE) spectra of PSCs without (control) and with BP deposition (1~3 times) on perovskite film surface. e Histogram of power conversion efficiencies (PCEs) of PSCs without (control) and with BP modification (BP coating for 2 times). The PCEs are derived from the reverse scans of the J-V curves. f The average PCE enhancement after the modification of perovskite films with different 2-D materials. CREDIT by Peng You, Guanqi Tang, Jiupeng Cao, Dong Shen, Tsz-Wai Ng, Zafer Hawash, Naixiang Wang, Chun-Ki Liu, Wei Lu, Qidong Tai, Yabing Qi, Chun-Sing Lee, Feng Yan

Abstract:
Grain boundaries (GBs) in PSCs have been found to be detrimental to the photovoltaic performance of the devices. Numerous papers reported that the defects in perovskite GBs should be passivated by suitable materials, such as quaternary ammonium halide, fullerene derivatives and CH3NH3I, to alleviate carrier recombination and consequently improve the device performance.

2D materials for conducting hole currents from grain boundaries in perovskite solar cells

Changchun, China | Posted on April 2nd, 2021

In a new paper published in Light: Science & Applications, a team of scientists, led by Professor Feng Yan from Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, and co-workers have developed a novel method to overcome the drawback of perovskite GBs without defect passivation on them. Several 2-D materials, including black phosphorus (BP), MoS2 and graphene oxide (GO), are specifically modified on the edge of perovskite GBs by a solution process. The 2-D materials have high carrier mobilities, ultrathin thicknesses and smooth surfaces without dangling bonds. The PCEs of the devices are substantially enhanced by the 2-D flakes, in which BP flakes can induce the highest relative enhancement of about 15%. More interestingly, they find that, under certain conditions, GBs modified with the 2-D materials are favorable for the device performance. Therefore, a synergistic effect between the 2-D flakes and perovskite GBs is observed for the first time. Although the nanotechnology of using 2-D materials in PSCs has been reported in some papers, the synergistic effect between the 2-D flakes and perovskite GBs has not been reported until now. To better understand the underlying mechanism of the above effect, device simulation was conducted by using a commercial software. The hole conduction processes from GBs to 2-D flakes in PSCs are clearly demonstrated, showing that the GBs and 2-D flakes all act as hole channels in the devices. The simulation results confirm that the performance enhancement induced by BP is higher than that by other 2-D materials because of the highest hole mobility of BP. In addition, the modification of the 2-D flakes on the perovskite grains away from GBs has little effect on the device performance, indicating that the synergistic effect of 2-D flakes and perovskite GBs is essential to the performance enhancement in our devices.

Although the coverage of the 2-D flakes on the perovskite films is only several percent, most of the flakes are located on perovskite GBs. Due to the high carrier mobilities of the 2-D materials especially BP, hole transfer from GBs is dramatically enhanced in the PSCs, resulting in substantial improvements of the efficiency as well as the stability of the devices. These results also indicate that GBs in PSCs are not detrimental to the device performance if the accumulated holes in the GBs can be conducted out efficiently. Under certain conditions, GBs even can be favorable for the photovoltaic performance of PSCs due to the built-in electric fields around them, which can facilitate photocarrier separation and transfer in the devices. Therefore, perovskite GBs are electrically benign, which is consistent with some theoretical calculations reported before. More importantly, they observed the synergic effect of the 2D flakes on the GBs in PSCs for the first time. Both the carrier mobility and the location of the 2D flakes on the perovskite surface are essential to the performance enhancement. This work provides a guideline of modifying perovskite layers with novel high-mobility 2-D materials to improve the photovoltaic performance as well as the stability of PSCs.

####

For more information, please click here

Contacts:
Feng Yan

Copyright © Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

RELATED JOURNAL ARTICLE:

Related News Press

2 Dimensional Materials

Hanging by a thread: Imaging and probing chains of single atoms: Scientists develop a method to visualize monoatomic chains and measure the strength and conductance of single-atom bonds May 14th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

News and information

Hanging by a thread: Imaging and probing chains of single atoms: Scientists develop a method to visualize monoatomic chains and measure the strength and conductance of single-atom bonds May 14th, 2021

Nanophotonics enhanced coverslip for phase imaging in biology May 14th, 2021

New technology enables rapid sequencing of entire genomes of plant pathogens May 14th, 2021

Harvesting light like nature does:Synthesizing a new class of bio-inspired, light-capturing nanomaterials May 14th, 2021

Perovskites

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Polarization-sensitive photodetection using 2D/3D perovskite heterostructure crystal May 4th, 2021

Possible Futures

Emergence of a new heteronanostructure library May 14th, 2021

New technology enables rapid sequencing of entire genomes of plant pathogens May 14th, 2021

Harvesting light like nature does:Synthesizing a new class of bio-inspired, light-capturing nanomaterials May 14th, 2021

You're so vein: Scientists discover faster way to manufacture vascular materials May 14th, 2021

Discoveries

Emergence of a new heteronanostructure library May 14th, 2021

Hanging by a thread: Imaging and probing chains of single atoms: Scientists develop a method to visualize monoatomic chains and measure the strength and conductance of single-atom bonds May 14th, 2021

Nanophotonics enhanced coverslip for phase imaging in biology May 14th, 2021

You're so vein: Scientists discover faster way to manufacture vascular materials May 14th, 2021

Announcements

Emergence of a new heteronanostructure library May 14th, 2021

Nanophotonics enhanced coverslip for phase imaging in biology May 14th, 2021

New technology enables rapid sequencing of entire genomes of plant pathogens May 14th, 2021

Harvesting light like nature does:Synthesizing a new class of bio-inspired, light-capturing nanomaterials May 14th, 2021

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Hanging by a thread: Imaging and probing chains of single atoms: Scientists develop a method to visualize monoatomic chains and measure the strength and conductance of single-atom bonds May 14th, 2021

Nanophotonics enhanced coverslip for phase imaging in biology May 14th, 2021

New technology enables rapid sequencing of entire genomes of plant pathogens May 14th, 2021

Harvesting light like nature does:Synthesizing a new class of bio-inspired, light-capturing nanomaterials May 14th, 2021

Energy

Emergence of a new heteronanostructure library May 14th, 2021

A silver lining for extreme electronics April 30th, 2021

Less innocent than it looks: Hydrogen in hybrid perovskites: Researchers identify the defect that limits solar-cell performance April 30th, 2021

Wearable sensors that detect gas leaks April 19th, 2021

Solar/Photovoltaic

Harvesting light like nature does:Synthesizing a new class of bio-inspired, light-capturing nanomaterials May 14th, 2021

Less innocent than it looks: Hydrogen in hybrid perovskites: Researchers identify the defect that limits solar-cell performance April 30th, 2021

A PTV-based polymer enabled organic solar cells with over 16% efficiency April 2nd, 2021

A general approach to high-efficiency perovskite solar cells April 1st, 2021

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project