Shape adaptable and highly resilient 3D braided triboelectric nanogenerators as e-textiles for power and sensing.

Combining traditional textiles with triboelectric nanogenerators (TENGs) gives birth to self-powered electronic textiles (e-textiles). However, there are two bottlenecks in their widespread application, low power output and poor sensing capability. Herein, by means of the three-dimensional five-directional braided (3DB) structure, a TENG-based e-textile with the features of high flexibility, shape adaptability, structural integrity, cyclic washability, and superior mechanical stability, is designed for power and sensing.

Alternating Current Photovoltaic Effect.

It is well known that the photovoltaic effect produces a direct current (DC) under solar illumination owing to the directional separation of light-excited charge carriers at the p-n junction, with holes flowing to the p-side and electrons flowing to the n-side. Here, it is found that apart from the DC generated by the conventional p-n photovoltaic effect, there is another new type of photovoltaic effect that generates alternating current (AC) in the nonequilibrium states when the illumination light periodically shines at the junction/interface of materials. The peak current of AC at high switching frequency can be much higher than that from DC.

Quantifying electron-transfer in liquid-solid contact electrification and the formation of electric double-layer.

Contact electrification (CE) has been known for more than 2600 years but the nature of charge carriers and their transfer mechanisms still remain poorly understood, especially for the cases of liquid-solid CE. Here, we study the CE between liquids and solids and investigate the decay of CE charges on the solid surfaces after liquid-solid CE at different thermal conditions. The contribution of electron transfer is distinguished from that of ion transfer on the charged surfaces by using the theory of electron thermionic emission.

Flexible and durable wood-based triboelectric nanogenerators for self-powered sensing in athletic big data analytics.

In the new era of internet of things, big data collection and analysis based on widely distributed intelligent sensing technology is particularly important. Here, we report a flexible and durable wood-based triboelectric nanogenerator for self-powered sensing in athletic big data analytics. Based on a simple and effective strategy, natural wood can be converted into a high-performance triboelectric material with excellent mechanical properties, such as 7.

Quantifying the triboelectric series.

Triboelectrification is a well-known phenomenon that commonly occurs in nature and in our lives at any time and any place. Although each and every material exhibits triboelectrification, its quantification has not been standardized. A triboelectric series has been qualitatively ranked with regards to triboelectric polarization.

Contact-Electrification between Two Identical Materials: Curvature Effect.

It is known that contact-electrification (or triboelectrification) usually occurs between two different materials, which could be explained by several models for different materials systems ( Adv. Mater. 2018, 30, 1706790; Adv.

Dramatically Enhanced Broadband Photodetection by Dual Inversion Layers and Fowler-Nordheim Tunneling.

Silicon photonics is now widely accepted as a key technology in a variety of systems. But owing to material limitations, now it is challenging to greatly improve the performance after decades of development. Here, we show a high-performance broadband photodetector with significantly enhanced sensitivity and responsivity operating over a wide wavelength range of light from near-ultraviolet to near-infrared at low power consumption.

Raising the Working Temperature of a Triboelectric Nanogenerator by Quenching Down Electron Thermionic Emission in Contact-Electrification.

As previously demonstrated, contact-electrification (CE) is strongly dependent on temperature, however the highest temperature in which a triboelectric nanogenerator (TENG) can still function is unknown. Here, by designing and preparing a rotating free-standing mode Ti/SiO TENG, the relationship between CE and temperature is revealed. It is found that the dominant deterring factor of CE at high temperatures is the electron thermionic emission.

On the Electron-Transfer Mechanism in the Contact-Electrification Effect.

A long debate on the charge identity and the associated mechanisms occurring in contact-electrification (CE) (or triboelectrification) has persisted for many decades, while a conclusive model has not yet been reached for explaining this phenomenon known for more than 2600 years! Here, a new method is reported to quantitatively investigate real-time charge transfer in CE via triboelectric nanogenerator as a function of temperature, which reveals that electron transfer is the dominant process for CE between two inorganic solids. A study on the surface charge density evolution with time at various high temperatures is consistent with the electron thermionic emission theory for triboelectric pairs composed of Ti-SiO and Ti-Al O . Moreover, it is found that a potential barrier exists at the surface that prevents the charges generated by CE from flowing back to the solid where they are escaping from the surface after the contacting.