Chapter 18
Interfacial Materials for Organic Solar
Cells
Amaresh Mishra
Abstract Organic solar cell (OSC) is one of the promising photovoltaic technology for next generation low-cost renewable energy sources. The power conversion
efficiencies (PCE) of OSCs have reached above 14% in single-junction and ~17%
in tandem OSCs. This rapid increase in the performance is mostly profited from the
synergetic advances in rational molecular design, device processing and interfacial
layer modifications. In addition to the development of efficient photoactive materials,
interfacial design plays a crucial role in the improvement of device performance and
stability. Most importantly, the interfacial layer is responsible for establishing good
ohmic contact in the device, thus minimize the resistance, interfacial recombination
and improve charge selectivity. In this chapter, we present the recent development
in the electron and hole transporting interfacial materials design for both singlejunction and tandem OSCs. Special attention will be paid to the design principles
of interfacial materials which includes inorganic metal oxides, composite materials,
oligomeric and polymeric molecules and their use as cathode and anode interlayer
for high efficiency devices. The structure-property relationships of various interfacial
materials will be analyzed as an approach towards high performance OSCs. Finally,
we will discuss the current challenges with possible solutions and perspectives for
performance enhancement in OSCs.
Keywords Interfacial material · Organic semiconductor · Cathode interlayer ·
Anode interlayer · Organic solar cell
18.1 Introduction
Solution-processed organic solar cells (OSC) using π-conjugated organic materials
as active layer components have shown significant advance in recent years with power
conversion efficiency (PCE) in the range from 10–14% in single bulk-heterojunction
devices (Mishra and Bäuerle 2012; Li et al. 2019; Zhang et al. 2018a, b; Xiao et al.
A. Mishra (B)
School of Chemistry and Nano Research Centre, Sambalpur
University, Jyoti Vihar, Sambalpur, India
e-mail: amaresh.mishra@suniv.ac.in
© Springer Nature Singapore Pte Ltd. 2020
H. Tyagi et al. (eds.), Solar Energy, Energy, Environment,
and Sustainability, https://doi.org/10.1007/978-981-15-0675-8_18
373
Interfacial Materials for Organic Solar
Cells
Amaresh Mishra
Abstract Organic solar cell (OSC) is one of the promising photovoltaic technology for next generation low-cost renewable energy sources. The power conversion
efficiencies (PCE) of OSCs have reached above 14% in single-junction and ~17%
in tandem OSCs. This rapid increase in the performance is mostly profited from the
synergetic advances in rational molecular design, device processing and interfacial
layer modifications. In addition to the development of efficient photoactive materials,
interfacial design plays a crucial role in the improvement of device performance and
stability. Most importantly, the interfacial layer is responsible for establishing good
ohmic contact in the device, thus minimize the resistance, interfacial recombination
and improve charge selectivity. In this chapter, we present the recent development
in the electron and hole transporting interfacial materials design for both singlejunction and tandem OSCs. Special attention will be paid to the design principles
of interfacial materials which includes inorganic metal oxides, composite materials,
oligomeric and polymeric molecules and their use as cathode and anode interlayer
for high efficiency devices. The structure-property relationships of various interfacial
materials will be analyzed as an approach towards high performance OSCs. Finally,
we will discuss the current challenges with possible solutions and perspectives for
performance enhancement in OSCs.
Keywords Interfacial material · Organic semiconductor · Cathode interlayer ·
Anode interlayer · Organic solar cell
18.1 Introduction
Solution-processed organic solar cells (OSC) using π-conjugated organic materials
as active layer components have shown significant advance in recent years with power
conversion efficiency (PCE) in the range from 10–14% in single bulk-heterojunction
devices (Mishra and Bäuerle 2012; Li et al. 2019; Zhang et al. 2018a, b; Xiao et al.
A. Mishra (B)
School of Chemistry and Nano Research Centre, Sambalpur
University, Jyoti Vihar, Sambalpur, India
e-mail: amaresh.mishra@suniv.ac.in
© Springer Nature Singapore Pte Ltd. 2020
H. Tyagi et al. (eds.), Solar Energy, Energy, Environment,
and Sustainability, https://doi.org/10.1007/978-981-15-0675-8_18
373