We demonstrate Si nanohole arrays as a superior sunlight-absorbing nanostructure for photovoltaic solar cell applications. Under 1 sun AM1.5G illumination, a Si nanohole solar cell with p-n junctions via P diffusion exhibited a open-circuit voltage of 566.6 mV, a short-circuit current density of 32.2 mA/cm(2), and a remarkable power conversion efficiency of 9.51%, which is higher than that of its counterparts based on Si nanowires, planar Si, and pyramid-textured Si. The nanohole array geometry presents a novel and viable method fo cost-efficient solar energy conversion.

High-density aligned n-type silicon nanowire (SiNW) arrays decorated with discrete 5-10 nm platinum nanoparticles (PtNPs) have been fabricated by aqueous electroless Si etching followed by an electroless platinum deposition process. Coating of PtNPs on SiNW sidewalls yielded a substantial enhancement in photoconversion efficiency and an apparent energy conversion efficiency of up to 8.14% for the PtNP-decorated SiNW-based photoelectrochemical solar cell using a liquid electrolyte containing Br(-)/Br(2) redox couple. The results demonstrate PtNP-decorated SiNWs to be a promising hybrid system for solar energy conversion.

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Silicon nanowires (SiNWs) arrays prepared by electroless etching show excellent optical antireflectivity over a wide spectral bandwidth from 300to1000nm and surface defect-induced electrical conductivity. Both characteristics make the SiNWs a promising material for photovoltaic cell applications. Photoelectrochemical (PEC) measurements showed the electroless etching SiNWs are remarkably photoactive and effective in enhancing photovoltaic properties including photocurrent and photovoltage. Since electroless etching can enable simple, wafer-scale fabrication of SiNWs without the need of doping. SiNWs array thus prepared show great promise as low-cost and scalable photovoltaic-type PEC materials.

Rational regulation on polysulfide behaviors is of great significance in pursuit of reliable solution-based lithium–sulfur (Li–S) battery chemistry. Herein, we develop a unique polymeric zwitterion (PZI) to establish a smart polysulfide regulation in Li–S batteries. The zwitterionic nature of PZI integrates sulfophilicity and lithiophilicity in the matrix, fostering an ionic environment for selective ion transfer through the chemical interactions with lithium polysulfides (LiPS). When implemented as a functional interlayer in the cell configuration, PZI empowers strong obstruction against polysulfide permeation but simultaneously allows fast Li+ conduction, thus contributing to significant shuttle inhibition as well as the resultant facile and stable sulfur electrochemistry. The PZI-based cells realize excellent cyclability over 1000 cycles with a minimum capacity fading rate of 0.012% per cycle and favorable rate capability up to 5 C. Moreover, a high areal capacity retention of 5.3 mAh cm–2 after 300 cycles can be also obtained under raised sulfur loading and limited electrolyte, demonstrating great promise in developing high-efficiency and long-lasting Li–S batteries.

Recent fruitful studies on rechargeable zinc-air battery have led to emergence of various bifunctional oxygen electrocatalysts, especially metal-based materials. However, their electrocatalytic configuration and evolution pathway during battery operation are rarely spotlighted. Herein, to depict the underlying behaviors, a concept named dynamic electrocatalyst is proposed. By selecting a bimetal nitride as representation, a current-driven "shell-bulk" configuration is visualized via time-resolved X-ray and electron spectroscopy analyses. A dynamic picture sketching the generation and maturation of nanoscale oxyhydroxide shell is presented, and periodic valence swings of performance-dominant element are observed. Upon maturation, zinc-air battery experiences a near twofold enlargement in power density to 234 mW cm −2 , a gradual narrowing of voltage gap to 0.85 V at 30 mA cm −2 , followed by stable cycling for hundreds of hours. The revealed configuration can serve as the basis to construct future blueprints for metal-based electrocatalysts, and push zinc-air battery toward practical application.

We demonstrate that the porous silicon nanowires (SiNWs) prepared by metal-assisted chemical etching method could impart sensitivity of nanowire electrical properties to gaseous nitrogen oxide (NO) at room temperature, thus are suitable for sensing NO and air monitoring. Particularly, the sensors made from the porous SiNWs assembly showed fast response and excellent reversibility to subparts per million NO concentrations. The excellent sensing performance coupled with scalable synthesis of porous SiNWs could open up opportunities in scalable production of sensor chips working at room temperature.

Nanowire solar cells: Pt nanoparticle (PtNP) decorated C/Si core/shell nanowire photoelectrochemical solar cells show high conversion efficiency of 10.86 % and excellent stability in aggressive electrolytes under 1-sun AM 1.5 G illumination. Superior device performance is achieved by improved surface passivation of the nanowires by carbon coating and enhanced interfacial charge transfer by PtNPs.