One of the most promising techniques for manufacturing low-cost solar cells is a solution processing method. In this study, it is proposed that solution-grown ZnO nanorods (NRs) are used as antireflection coatings on metal-insulator-semiconductor (MIS) solar cells with sol-gel SiO₂. Except Al electrodes prepared by thermal evaporation, no other vacuum process was utilized during fabrication. The ZnO NRs were produced with a hydrothermal method and suppressed Fresnel reflection. With the solution-grown ZnO NRs, it was observed the average reflectance of the MIS solar cell decreased from 38.7% to 15.8%, and the short circuit density (J_SC) increased from 5.22 mA/cm² to 6.71 mA/cm² (28.4% enhancement). Meanwhile, the open circuit voltage (V_OC) was improved from 0.39 V to 0.47 V owing to a passivation effect. The MIS solar cell with the ZnO NRs exhibited a 35.5% efficiency enhancement compared to that without ZnO NRs. The performance improvement in MIS solar cells with ZnO NRs could be due to multiple reflections of an incident light between the vertically arranged NRs, and then light coupling into the cell. The results show a potential application of ZnO NRs for the performance enhancement of MIS solar cells.

In this paper, it is reported that a metal-free and non-conjugated polymer, MA-PEG 8000-BADGE (MP8B), exhibits an antireflective property and substrate-dependent photoluminescence (SDP). MP8B was constructed from maleic anhydride, poly(ethylene glycol) and bisphenol-A diglycidyl ether. Self-assembled nanoparticles are found in MP8B and can prospectively act as scattering centers to improve light trapping and extraction. MP8B films prepared from MP8B solutions have been characterized by photoluminescence (PL), atomic force microscopy (AFM), tunnelling electron microscope (TEM), reflectance, transmittance, and UV-Vis absorption spectrum. MP8B films can suppress light reflection and enhance light transmission. The PL spectrum of MP8B film on ITO peaks at approximately 538 nm, spanning from 450 to 660 nm at a concentration of 25 mM. Meanwhile, the effects of concentration and substrate on the PL of MP8B films are also investigated in this study. Surface roughness becomes larger with concentration. A red shift of the PL spectrum is observed as solution concentration increases. Meanwhile, aggregation-caused quenching (ACQ) is insignificant. Moreover, the PL spectra of MP8B films show a substrate-dependent phenomenon due to dielectric screening. The optical band-gap energy of MP8B is approximately 4.05 eV. It is concluded that MP8B is a promising candidate for a host material, and its film can be utilized as a multifunctional layer (i.e., antireflective and light-scattering functions) for optoelectronic applications.

Anhydride-poly(ethylene glycol) co-polymer (A-PEGCP) has been synthesized from maleic anhydride, poly(ethylene glycol) and bisphenol-A diglycidyl ether without using any organic solvent. The thin films produced from A-PEGCP solution were spin-coated on ITO-coated glass. The nanoparticles are observed in the thin films. It is proposed that the nanoparticle is built by a self-assembly process with bisphenol-A aggregates and poly (ethylene glycol) moieties. The effects of concentration, thermal annealing, excitation wavelength and moisture on the optical and nanostructured characterization of the thin films are investigated in this study. Photoluminescence (PL) spectrum of the thin film on ITO-coated glass has a peak of about 450 nm that extends from 360 to 550 nm under 325 nm excitation. The increase in PL intensity is accompanied by a red shift of PL spectrum as concentration increases. Moreover, the slightly red shift of PL spectrum is also observed as annealing temperature increases. Meanwhile, PL intensity negligibly decreases with annealing temperature. The degradation in PL intensity is apparent due to moisture. The excitation-wavelength dependent photoluminescence (EWDP) is observed in the thin film. UV-Vis absorption spectra of the thin films are red-shifted with concentration due to more molecular aggregation. The highest occupied molecular orbital (HOMO) energy is −9.52 eV. The optical band-gap energy is 4.09–4.44 eV.

The metal-oxide-semiconductor (MOS) solar cells with sol-gel derived silicon dioxides (SiO2) deposited by spin coating are proposed in this study. The sol-gel derived SiO2 layer is prepared at low tem

Nonconjugated polymers have been synthesized from maleic anhydride, poly(ethylene glycol), and bisphenol-diglycidyl ether without utilizing any solvent. The polymeric thin films produced by the nonconjugated polymers were spin-coated on ITO coated glass and Si substrates. Self-assembly nanoparticles (1.6-6.2 nm) are observed. It is proposed that the nanoparticle is constructed through a self-assembly process with bisphenol-A aggregates and poly(ethylene glycol) moieties. The photoluminescence spectrum of the polymeric thin film on ITO peaks at near 450 nm that spans from 360 to 610 nm under 266 nm excitation. The polymeric thin film exhibits the excitation-wavelength-dependent photoluminescence that the emission peak shifts toward longer wavelength (about 11 nm) when the excitation wavelength increases from 266 to 325 nm, which is attributed to nanoparticle size distribution. Meanwhile, the substrate-dependent photoluminescence has been also observed that the PL peak of the polymeric thin film spin-coated on Si shows a blue shift (about 9 nm) compared with that on ITO, which probably arises from the dielectric screening. The highest occupied molecular orbital energy of the polymeric thin film is about -9.4 eV. The optical band gap is about 3.28 eV. The nonconjugated polymer is expected to use as a host material in optoelectronic applications.