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An organic conductive polymer is used to improve charge transport and efficiency in carbon nanotube–silicon solar cells.

Silica nanoparticles were synthesized from rice husk ash at room temperature by using high energy planetary ball mill. The milling time and mill rotational speed were varied in four levels. The morphology of the synthesized powders was investigated by the FE-SEM and TEM image as well as XRD patterns. The results have revealed that the nano-sized amorphous silica particles are formed after about 6 h ball milling and they are spherical in shape. The average particle size of the silica powders is found to be around 70 nm which decreases with increasing ball milling time or mill rotational speed. The as-synthesized silica nanoparticles were subsequently employed as drug carrier to investigate in vitro release behavior of Penicillin-G in simulated body fluid. UV-Vis spectroscopy was used to determine the amount of Penicillin-G released from the carrier. Penicillin-G release profile from silica nanoparticles exhibited a delayed release effect.

Carbon nanotube-silicon (CNT-Si)-based heterojunction solar cells (HJSCs)are a promising photovoltaic (PV) system. Herein, few-layer black phosphorus (FL-BP) sheets are produced in N-methyl-2-pyrrolidone (NMP) using microwave-assisted liquid-phase exfoliation and introduced into the CNTs-Sibased HJSCs for the first time. The NMP-based FL-BP sheets remain stable after mixing with aqueous CNT dispersion for device fabrication. Due to their unique 2D structure and p-type dominated conduction, the FL-BP/NMP incorporated CNT-Si devices show an impressive improvement in the power conversion efficiency from 7.52% (control CNT-Si cell) to 9.37%. Our densityfunctional theory calculation reveals that lowest unoccupied molecular orbital (LUMO) of FL-BP is higher in energy than that of single-walled CNT. Therefore, we observed a reduction in the orbitals localized on FL-BP upon highest occupied molecular orbital to LUMO transition, which corresponds to an improved charge transport. This study opens a new avenue in utilizing 2D phosphorene nanosheets for next-generation PVs.

Antireflection layers are commonly used in photovoltaics to increase light absorption and therefore increase maximum photocurrent. Here, pyramid structures are created on Si surfaces with alkaline solution etching. The extent of pyramid coverage depends directly on the reaction time and as a result, the surface reflectance decreases with reaction time. A floating transfer method is used to fabricate heterojunction solar cells based on graphene oxide‐carbon nanotube and Si heterojunctions. The best device performance (photo current conversion efficiency of 13.01 ± 0.32%, which is much higher than the efficiency of the control devices (10.18 ± 0.33%)) was observed using with cells fabricated with the highest coverage (99.9%) of pyramids on the Si surfaces, which is determined to be a combined effect of reduced surface reflectance and increased effective heterojunction area per unit active area.

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Graphene oxide/single-wall carbon nanotube (GOCNT) hybrid films have been used to fabricate heterojunction solar cells with silicon (Si) due to their compatibility with both aqueous and organic processing. In these cells GOCNT films are required to be both highly transparent and conducting.Different approaches are used to improve these optoelectronic properties of the GOCNT films, including hybridization with silver nanowires (AgNWs) and p-type doping with CuCl 2 , AuCl 3 , SOCl 2 , HCl, H 2 SO 4 , HNO 3 and HClO 4 . UV-vis-NIR absorbance, Raman spectroscopy, and the sheet resistance of the films were used to evaluate the properties of the treated films and quantify doping. The most effective way to improve the optoelectronic properties of the GOCNT films was the incorporation of AgNWs which improved the figure of merit (FOM, the ratio of transparency and conductivity) by over 600%. However, GOCNT/Si heterojunction photovoltaic devices with HNO 3 doped GOCNT films showed the highest solar photocurrent conversion efficiency (11.38 AE 0.26%). In terms of stability, CuCl 2 and HCl doped films have the best electrode FOM stability, and devices made with such films have the most stable efficiency as well. This report suggests that the electronegativity of the active elements in the dopants has a strong influence on the optoelectronic properties of the films as well as the solar cell performance.