TY - JOUR
T1 - Granum-like stacking structures with TiO2-graphene nanosheets for improving photo-electric conversion
AU - Yang, Nailiang
AU - Zhang, Yu
AU - Halpert, Jonathan E.
AU - Zhai, Jin
AU - Wang, Dan
AU - Jiang, Lei
PY - 2012/6/11
Y1 - 2012/6/11
N2 - Solar energy is commonly considered to be one of the most important forms of future energy production. This is due to its ability to generate essentially free power, after installation, with low environmental impact. Green plants, meanwhile, exhibit a process for light-to-charge conversion that provides a useful model for using solar radiation efficiently. Granum, the core organ in photosynthesis consists of a stack of ~10-100 thylakoids containing pigments and electrons acceptors. Imitating the structure and function of granum, stacked structures are fabricated with TiO2/graphene nanosheets as the thylakoids unit, and their photo-electric effect is studied by varying the number of layers present in the film. The photo-electric response of the graphene composites are found to be 20 times higher than that of pure TiO 2 in films with 25 units stacked. Importantly, the cathodic photocurrent changes to anodic photocurrent as the thickness increases, an important feature of efficient solar cells which is often ignored. Here graphene is proposed to perform similarly to the b6f complex in granum, by separating charges and transporting electrons through the stacked film. Using this innovation, stacked TiO2/graphene structures are now able to significantly increase photoanode thickness in solar cells without losing the ability to conduct electrons.
AB - Solar energy is commonly considered to be one of the most important forms of future energy production. This is due to its ability to generate essentially free power, after installation, with low environmental impact. Green plants, meanwhile, exhibit a process for light-to-charge conversion that provides a useful model for using solar radiation efficiently. Granum, the core organ in photosynthesis consists of a stack of ~10-100 thylakoids containing pigments and electrons acceptors. Imitating the structure and function of granum, stacked structures are fabricated with TiO2/graphene nanosheets as the thylakoids unit, and their photo-electric effect is studied by varying the number of layers present in the film. The photo-electric response of the graphene composites are found to be 20 times higher than that of pure TiO 2 in films with 25 units stacked. Importantly, the cathodic photocurrent changes to anodic photocurrent as the thickness increases, an important feature of efficient solar cells which is often ignored. Here graphene is proposed to perform similarly to the b6f complex in granum, by separating charges and transporting electrons through the stacked film. Using this innovation, stacked TiO2/graphene structures are now able to significantly increase photoanode thickness in solar cells without losing the ability to conduct electrons.
KW - artificial granum
KW - charge transport
KW - graphene
KW - photo-electric conversion
KW - stacked structures
KW - TiO
UR - http://www.scopus.com/inward/record.url?scp=84861910728&partnerID=8YFLogxK
U2 - 10.1002/smll.201200079
DO - 10.1002/smll.201200079
M3 - Article
C2 - 22454277
AN - SCOPUS:84861910728
SN - 1613-6810
VL - 8
SP - 1762
EP - 1770
JO - Small
JF - Small
IS - 11
ER -