Chapter 10
Hot Carrier Transfer and Carrier
Manipulation of Semiconductor
Nanocrystals
Naoto Tamai and Sadahiro Masuo
Abstract Hot carrier transfer of semiconductor nanocrystals (NCs) plays an important role for solar energy conversion. In this chapter, effects of quantum confinement of colloidally synthesized semiconductor NCs on hot carrier transfer and the
carrier transfer mechanism are discussed on the basis of state-selective excitation of
femtosecond transient absorption spectroscopy and initial bleach yield of band-edge
state. The role of phonon emission from higher excited states on hot carrier transfer
in quantum-confined NCs is revealed. In addition, carrier manipulation of a single
semiconductor NC by plasmonic nanostructures is demonstrated with single particle
spectroscopy. The distance dependence between a single semiconductor quantum
dot (QD) and a plasmonic nanostructure on luminescence intensity and lifetime of a
single semiconductor QD is discussed in terms of the electromagnetic enhancement
of absorption and luminescence and energy transfer quenching by the plasmonic
nanostructure.
Keywords Hot carrier transfer · Semiconductor nanocrystal · Quantum
confinement · State-selective transient absorption spectroscopy · Phonon
emission · Carrier manipulation · Single particle spectroscopy · Energy transfer ·
Plasmonic nanostructure
10.1 Introduction
Colloidally synthesized semiconductor nanocrystals (NCs) have unique optical and
physical properties resulting from the strong confinement of electron and hole, which
can be used as promising materials such as photocatalysis and photovoltaics. One
N. Tamai (B)
Department of Chemistry, School of Science and Technology, Kwansei Gakuin University,
Sanda, Hyogo 669-1337, Japan
e-mail: tamai@kwansei.ac.jp
S. Masuo
Department of Applied Chemistry for Environment, School of Science and Technology,
Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
e-mail: masuo@kwansei.ac.jp
© Springer Nature Singapore Pte Ltd. 2020
H. Miyasaka et al. (eds.), Photosynergetic Responses in Molecules
and Molecular Aggregates, https://doi.org/10.1007/978-981-15-5451-3_10
171
Hot Carrier Transfer and Carrier
Manipulation of Semiconductor
Nanocrystals
Naoto Tamai and Sadahiro Masuo
Abstract Hot carrier transfer of semiconductor nanocrystals (NCs) plays an important role for solar energy conversion. In this chapter, effects of quantum confinement of colloidally synthesized semiconductor NCs on hot carrier transfer and the
carrier transfer mechanism are discussed on the basis of state-selective excitation of
femtosecond transient absorption spectroscopy and initial bleach yield of band-edge
state. The role of phonon emission from higher excited states on hot carrier transfer
in quantum-confined NCs is revealed. In addition, carrier manipulation of a single
semiconductor NC by plasmonic nanostructures is demonstrated with single particle
spectroscopy. The distance dependence between a single semiconductor quantum
dot (QD) and a plasmonic nanostructure on luminescence intensity and lifetime of a
single semiconductor QD is discussed in terms of the electromagnetic enhancement
of absorption and luminescence and energy transfer quenching by the plasmonic
nanostructure.
Keywords Hot carrier transfer · Semiconductor nanocrystal · Quantum
confinement · State-selective transient absorption spectroscopy · Phonon
emission · Carrier manipulation · Single particle spectroscopy · Energy transfer ·
Plasmonic nanostructure
10.1 Introduction
Colloidally synthesized semiconductor nanocrystals (NCs) have unique optical and
physical properties resulting from the strong confinement of electron and hole, which
can be used as promising materials such as photocatalysis and photovoltaics. One
N. Tamai (B)
Department of Chemistry, School of Science and Technology, Kwansei Gakuin University,
Sanda, Hyogo 669-1337, Japan
e-mail: tamai@kwansei.ac.jp
S. Masuo
Department of Applied Chemistry for Environment, School of Science and Technology,
Kwansei Gakuin University, Sanda, Hyogo 669-1337, Japan
e-mail: masuo@kwansei.ac.jp
© Springer Nature Singapore Pte Ltd. 2020
H. Miyasaka et al. (eds.), Photosynergetic Responses in Molecules
and Molecular Aggregates, https://doi.org/10.1007/978-981-15-5451-3_10
171