Optimizing the light absorption of graphene-based organic solar cells by tailoring the weak microcavity with dielectric/graphene/dielectric multilayer

Abstract

Investigation into the organic solar cells (OSCs) with graphene electrode demonstrates that the weak-microcavity (WMC) constructed between the transparent electrode and top metal electrode plays an important role in the absorption properties of the devices. If the WMC structure is not optimized, the absorption of the graphene-based devices cannot surpass that of OSC devices with indium tin oxide electrode. By employing dielectric/graphene/dielectric multilayer to optimize the WMC, the absorption can be improved by a maximum value of 21.1% within a broad wavelength range of 410–636 nm. Correspondingly, an improvement of 12.1% in total absorbed photons is achieved for the device.

Simultaneously improving optical absorption of both transverse-electric polarized and transverse-magnetic polarized light for organic solar cells with Ag grating used as transparent electrode

“…The transmitted light can make round trips between the Glass/WO 3 interface and the Ag back electrode, and a WMC structure is constructed with the Glass/WO 3 interface and the Ag back electrode as mirrors. [20][21][22][23] This microcavity is nearly resonant within the red wavelength range and can confine relatively large photons in the active layer (see the supporting materials). 23 As a result, the optical electric field behind the slits grows larger in Device B than in Device A (see Fig.…”

“…23 Around this wavelength range, optical resonance of the WMC can improve the optical electric field and light absorption in the active layer. [20][21][22] As to the light with wavelength of 450 nm, it is revealed from Fig. 5(a) that large electric field is confined behind the Ag strip in grating.…”

STS observations of deep defects within laser-illuminated graphene/MOVPE-h-BN heterostructures

“…For 2D materials, particularly important is the possibility of creating layered vertical heterostructures, where a broad range of properties of the system can be tailored and adjusted. 11,12 The heterostructure composed of the aforementioned materials-graphene and h-BN, is proposed for various applications, such as photovoltaics 6,13 or electronics, 14 where encapsulating graphene in h-BN leads to an increase in charge carrier mobility. 9 The above described properties of the two-dimensional nanomaterials, graphene and h-BN in particular, give promise of creating complex electronic and optoelectronic systems, while maintaining a small size required by trends of miniaturization of technology.…”