Realization of 16.9% Efficiency on Nanowires Heterojunction Solar Cells with Dopant‐Free Contact for Bifacial Polarities

Abstract

Low-cost and efficient interfacial layer construction with the required charge selectivity and compatibility is necessary for nanostructured solar cells, and the proper integration of the interfacial layer with the light-trapping system is required to improve the power conversion efficiency of the cell. Herein, low-cost Si nanowires-based solar cells with tunneling heterojunctions are developed by the deposition of MoO x and spin-coating of Cs 2 CO 3 as the carrier-selective layers. The power conversion efficiency of 16.9% for a device of 4 cm 2 in area is achieved by Si nanowires solar cells by the self-assembly of ultra-thin SiO x as the surface tunneling passivation layer. Self-assembly is realized with an ultraviolet O 3 treatment process at room temperature. Quasi-steady-state photoconductance, microwave-detected photoconductance decay, and constant current-voltage measurements are used to characterize the passivation quality and tunneling transportation properties of the ultra-thin SiO x layers. Interfacial charge recombination is suppressed and effective carrier tunneling properties are developed by the growth of ≈1.5 nm thick SiO x layers on the surfaces of the Si nanowires. This proposed Si nanowires solar cell architecture featuring tunneling heterojunctions achieves high performance and may be suitable for fabricating industrialized Si nanowires-based photovoltaic devices through a cost-effective, simple, and low-temperature process.

Interface Dipole Induced Field‐Effect Passivation for Achieving 21.7% Efficiency and Stable Perovskite Solar Cells

“…Six O atoms are octahedrally coordinated with each Mo atom arranged into intertwined dual layers, which are fitted via van der Waals forces. [34,35] While in our study, the grazing-incidence X-ray diffraction (XRD) measurements confirm that the as-prepared 30 nm MoO x (on glass) is an amorphous phase. The hump at 25 o is contributed by the glass substrate.…”

“…Recently, we have observed this phenomenon in Si solar cells. [35,39] This charge transfer creates interfacial polarization, which induces the FEP by efficient separating photogenerated carriers and reducing the probability of Shockley-Read-Hall (SRH) recombination at the heterointerface. [40] Thus, we argue that the FEP caused by the MoO x interlayer may domain the photovoltaic improvement.…”

Indium‐rich InGaN/GaN solar cells with improved performance due to plasmonic and dielectric nanogratings

“…In this scheme, spheroidal silica and titania nanoparticle bilayers are present on top of the cell surface which confines the incident light into the solar cell through whispering gallery modes supported by silica nanoparticles and subsequent forward scattering into the high index absorber substrate by titania nanoparticles. Recently, it was demonstrated that semiconductor nanowire and nanotube heterojunctions can be employed for photovoltaic applications to enhance the light‐trapping capability as well as the electrical properties of solar cells . In these solar cells, the vertical junctions of radial diodes provide a charge carrier collection path separated from the photon‐absorbing layer thickness, allowing the carrier's collection along the radial direction, which results in the minimal recombination within the bulk semiconductor.…”

Compositional and structural engineering of inorganic nanowires toward advanced properties and applications

“…[9][10][11][12][13][14][15][16][17][18][19][20] Furthermore, more integrated devices with multifunctionalities have been investigated from both proof-of-concept and nanosystem integration perspectives. [21][22][23][24] Additionally, the nanowire configuration frequently exhibits reinforced mechanical properties compared to other configurations, including enhanced fracture resistance under bending (tensile) deformation and a tunable elastic modulus, making it advantageous for application in flexible devices and free-standing probes integrated with other functionalities. 25,26 To date, strategies for the controllable synthesis of nanowires with respect to their morphology, size, and crystal phase have been significantly developed.…”

“…Due to their abundant electrical, photonic, and mechanical properties, semiconductor nanowires, including Si, Ge, metal oxides, and III‐V and II‐VI compounds, have undergone great progress in the fields of electronics, subwavelength light waveguiding, and sensing (for photoelectric, chemical, and biological purposes) . Furthermore, more integrated devices with multifunctionalities have been investigated from both proof‐of‐concept and nanosystem integration perspectives . Additionally, the nanowire configuration frequently exhibits reinforced mechanical properties compared to other configurations, including enhanced fracture resistance under bending (tensile) deformation and a tunable elastic modulus, making it advantageous for application in flexible devices and free‐standing probes integrated with other functionalities …”