Cl-doped n-type CdS NWs with single-crystal wurtzite structure and [Formula: see text] growth direction were synthesized by using CdCl(2) as the dopant via a thermal co-evaporation method. By controlling the Cl vapor pressure during the growth, the conductivity of the CdS:Cl NWs can be tuned in a wide range of five orders of magnitude. A nano-photodetector based on the CdS:Cl NWs shows high sensitivity to visible light with excellent stability and reproducibility. Significantly, the photoconductivity of the CdS NWs is greatly enhanced by Cl doping and the responsivity and photoconductive gain of the CdS:Cl NWs have substantially increased compared with the undoped CdS NWs. Further study also demonstrates the polarization-dependent photoconductivity of the CdS:Cl NWs. It is expected that the CdS:Cl NWs with tunable optoelectronic properties will have important applications in high-performance nano-optoelectronic devices.

Spiro‐OMeTAD is one of the most used hole transport layers (HTLs) in high efficiency n‐i‐p perovskite solar cells (PSCs). However, due to the unsatisfactory conductivity of pristine Spiro‐OMeTAD, additives such as tert‐butylpyridine (tBP) and lithium bis (trifluoromethylsulfonyl)‐imide (LiTFSI) are required to improve its hole transportation. The hygroscopic nature of these additives inevitably deteriorates the device's stability. Here, it is shown that by adding fluorinated graphene (FG) into the Li‐TFSI and tBP doped Spiro‐OMeTAD, both efficiency and stability of the PSCs are significantly enhanced. Using the FG incorporated Spiro‐OMeTAD HTL, the power conversion efficiency (PCE) of the PSC reaches 21.92%, which is 11.8% higher than the original device. The FG not only improves the hole mobility of Spiro‐OMeTAD but also effectively reduces the amount of lithium ions in the perovskite layer and improves the hydrophobicity of the HTL. The FG incorporating cell shows better stability, maintaining 90% of initial efficiency over a 2400 h test in ambient conditions with 25% humidity. Finally, it is further demonstrated that the valence band of FG incorporated Spiro‐OMeTAD HTL has a positive effect on PSCs with a 2D interfacial layer, achieving an impressive PCE of 23.14% and a Voc of 1.226 V.

Harvesting solar energy for artificial photosynthesis is an emerging field in alternative energy research. In this work, the photocatalytic properties of InX(X=S, Se)/transition-metal disulfides (MoS2 and WS2) van der Waals...

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Coaxial ZnSe/Si nanocables were successfully produced by a simple two-step growth method. ZnSe nanowire cores were first synthesized by thermal evaporation and then followed by the chemical vapor deposition (CVD) growth of Si shells. The former have a cubic single-crystal structure with a longitudinal direction of [Formula: see text], while the latter are polycrystalline and composed of a large number of Si crystal grains with dominantly (111) surfaces. Controlled p-type doping to the Si shells was implemented by B diffusion after the shell growth. Electrical measurements on the Si shells demonstrated that the shell conductivity could be tuned in a wide range of eight orders of magnitude by adjusting the B concentration, and a hole mobility of 11.7 cm(2) V( - 1) s( - 1) and a hole concentration of 2 x 10(15) cm( - 3) were revealed for the modestly doped Si shells. The ZnSe/Si core/shell nanocables have great potential in nano-optoelectronic applications.