Improved efficiency and stability of inverse perovskite solar cells via passivation cleaning

Amidst the global energy and environmental crisis,the quest for efficient solar energy utilization intensifies.Perovskite solar cells,with efficiencies over 26%and cost-effective production,are at the forefront of research.Yet,their stability remains a barrier to industrial application.This study introduces innovative strategies to enhance the stability of inverted perovskite solar cells.By bulk and surface passivation,defect density is reduced,followed by a"passivation cleaning"using Apacl amino acid salt and isopropyl alcohol to refine film surface quality.Employing X-ray diffraction(XRD),scanning electron microscope(SEM),and atomic force microscopy(AFM),we confirmed that this process effectively neutralizes surface defects and curbs non-radiative recombination,achieving 22.6%efficiency for perovskite solar cells with the composition Cs_(0.15)FA_(0.85)PbI_(3).Crucially,the stability of treated cells in long-term tests has been markedly enhanced,laying groundwork for industrial viability.

Inhibiting radiative recombination rate to enhance quantum yields in a quantum photocell

Inhibiting the radiative radiation is an efficient approach to enhance quantum yields in a solar sell.This work carries out the inhibition of radiative recombination rate(RRR)in a quantum photocell with two coupled donors.We perform explicit calculations of the transition rates,energy gaps and the absorbed solar wavelength-dependent RRR,and find that two different regimes play the crucial roles in inhibiting RRR.One is the quantum coherence generated from two different transition channels,the other includes the absorbed photon wavelength and gaps between the donor and acceptor in this proposed photocell model.The results imply that there may be some efficient ways to enhance the photoelectron conversion compared to the classic solar cell.

Facile Preparation, Characterization of Flexible Organic Solar Cells Using P3HT-MWCNTS Composite Photoactive Layer

Multiwalled carbon nanotubes (MWCNTs) mixed in poly(3-hexylthiophene) (P3HT) were used as a photoactive layer for organic solar cells (OSC). The flexible OSCs of a structure of PET/rGO-P3HT/P3CT/PCBM/LiF-Al were prepared by spincoating. The UV-Vis absorption spectra of the photoactive films and current-voltage characteristics of the OSCs showed the advantage of the composite devices above the pristine-polymeric ones. Under illumination of light with a 100 mW/cm2-powerdensity, the photoelectrical conversion efficiency (PCE) of the OSCs with 3.0 wt% MWNCTs embedded in the photoactive layer possess a value as large as 2.35%. The obtained results suggest further useful applications of the flexible large-area solar cells.

A downshifting Eu^3+doped glass embedded with concave pyramid microstructure to improve the efficiency of silicon solar cell

The average photoelectric conversion efficiency(PCE)of a bare mono crystalline silicon solar cell is 14.71%±0.03%under AM1.5.It decreases to 14.20%±0.005%when covering an un-doped flat glass on the solar cell,and it goes down to 14.10%±0.005%by using a 5 wt%Eu^3+doped glass.The absorptions of the Eu^3+doped CPM glass one-to-one match the excitation spectra at 362,381,393,400,413 and464 nm,which are related to the transitions of 7 F0→(5 D4,5 G2,5 L6,5 D3),7 F1→5 D3,and 7 F0→5 D2,respectively.In addition,a concave pyramid microstructure(CPM)is embedded in the glass surface to increase light transmittance.The average PCE increases to 14.61%±0.07%when a 5 wt%Eu^3+doped CPM glass covers on the silicon solar cell.Compared with the un-doped flat glass,a net increase of the PCE is0.41%,where the 0.16%increment of PCE is from the lighting trapping of the CPM structure,and the downshifting of near ultraviolet(NUV)light by Eu^3+ion donates the other 0.25%increment.It confirms that the as-prepared Eu^3+doped CPM glass has a good downshifting and antireflection function.

Preparation of(Lu,Y)_(3)(Al,Sc,Cr)_(2)Al_(3)O_(12)phosphor ceramics with high thermal stability for near-infrared LED/LD

Near-infrared(NIR)phosphor-converted light-emitting diodes/laser diodes(LEDs/LDs)are prospective lighting sources for NIR spectroscopy.However,developing NIR phosphor materials with desired thermal robustness and high photoelectric efficiency is a crucial challenge for their applications.In this work,based on the cationic radius matching effect,a series of(Lu,Y)_(3)(Al,Sc,Cr)_(2)Al_(3)O_(12)NIR phosphor ceramics(LuYScCr NIR-PCs)were fabricated by vacuum sintering.Excellent thermal stability(95%@150℃)was obtained in the prepared NIR-PCs,owing to their weak electron-phonon coupling effect(small Huang-Rhys factor).Being excited at 460 nm,NIR-PCs realized a broadband emission(650-850 nm)with internal quantum efficiency(IQE)of 60.68%.Combining NIR-PCs with LED/LD chips,the maximum output power of the encapsulated LED prototype was 447 mW@300 mA with photoelectric efficiency of as high as 18.6%@180 mA,and the maximum output power of the LD prototype was 814 mW@2.5 A.The working temperatures of NIR-PCs were 70.8℃@300 mA(LED)and 102.8℃@3 A(LD).Finally,the prepared NIR-PCs applied in food detection were verified in this study,demonstrating their anticipated application prospects in the future.

CuInS_(2)/TiO_(2) heterojunction with elevated photo-electrochemical performance for cathodic protection

Semiconductor quantum dots with high quantum yield and photovoltaic conversion efficiency have ushered in a brilliant moment for constructing internal electric field heterojunctions for photogenerated cathodic protection applications.In this paper,TiO_(2)nanotubes grown vertically on the surface of titanium substrates were modified via a combination of conventional electrochemical oxidation and a one-step solvothermal pathway to sensitize with CuInS_(2)quantum dots.Compared with pure TiO_(2)photoelectrodes,the modification improves sunlight absorption efficiency and provides photoelectron cathodic protection to the 304 stainless steel(304 SS).Through 9 h solvothermal reaction,the CuInS_(2)/TiO_(2)coupled with protected 304 SS exhibited an excellent property when the simulated sunlight irradiation.Its mixed open circuit potential is negatively shifted to-0.99 V,at the mean time with a stable photocurrent density(118μA cm^(-2)).The results indicate that CuInS_(2)and TiO_(2)established a p-n heterojunction with wellmatched energy level,which can effectively facilitate the carrier separation and retain the strong redox capbility of photo-induced electrons and holes.

Design of a sector bowtie nano-rectenna for optical power and infrared detection

We designed a sector bowtie nanoantenna integrated with a rectifier （Au-TiOx-Ti diode） for collect- ing infrared energy. The optical performance of the metallic bowtie nanoantenna was numerically investigated at infrared frequencies （5-30 μm） using three-dimensional frequency-domain electro- magnetic field calculation software based on the finite element method. The simulation results indi- cate that the resonance wavelength and local field enhancement are greatly affected by the shape and size of the bowtie nanoantenna, as well as the relative permittivity and conductivity of the dielectric layer. The output current of the rectified nano-rectenna is substantially at nanoampere magnitude with an electric field intensity of 1 V/m. Moreover, the power conversion efficiency for devices with three different substrates illustrates that a substrate with a larger refractive index yields a higher efficiency and longer infrared response wavelength. Consequently, the optimized structure can pro- vide theoretical support for the design of novel optical rectennas and fabrication of optoelectronic devices.