Polarized Water Driven Dynamic PN Junction-Based Direct-Current Generator

Abstract

There is a rising prospective in harvesting energy from the environment, as in situ energy is required for the distributed sensors in the interconnected information society, among which the water flow energy is the most potential candidate as a clean and abundant mechanical source. However, for microscale and unordered movement of water, achieving a sustainable direct-current generating device with high output to drive the load element is still challenging, which requires for further exploration. Herein, we propose a dynamic PN water junction generator with moving water sandwiched between two semiconductors, which outputs a sustainable direct-current voltage of 0.3 V and a current of 0.64 μA. The mechanism can be attributed to the dynamic polarization process of water as moving dielectric medium in the dynamic PN water junction, under the Fermi level difference of two semiconductors. We further demonstrate an encapsulated portable power-generating device with simple structure and continuous direct-current voltage output of 0.11 V, which exhibits its promising potential application in the field of wearable devices and the IoTs.

Pyroelectric Nanogenerator Based on an SbSI–TiO2 Nanocomposite

“…As a result, the device generated a rectified electric output. The same effect is observed in the case of direct-current generators based on p – n [ 78 , 79 , 80 , 81 , 82 ] or Schottky [ 77 , 83 , 84 , 85 ] junctions. Morozovska et al [ 20 ] proposed that the rectification effect of the junction barrier allows the application of a ferroelectric nanowire array fixed between flat electrodes as the direct current generator.…”

Pursuing the tribovoltaic effect for direct-current triboelectric nanogenerators

“…3). 10,17,[20][21][22] The reported DC-TENGs can effectively convert mechanical energy directly into constant DC energy, which is more suitable for charging energy storage devices, powering portable electronics, or directly driving distributed sensors for the Internet of Things (IoTs). 8,17,18,[21][22][23][24] However, to the best of our knowledge, there are no review reports that systematically and comprehensively elaborate on DC-TENGs based on the tribovoltaic effect in terms of mechanism, material/structure, performance, external parameters, applications, etc.…”

“…42 Fig. 6 in detail evaluates various DC-TENG devices based on six different parameters, including current density, 5,[8][9][10]16,18,20,22,24,[43][44][45] peak power density, 5,8,9,[16][17][18]22,24,[43][44][45][46] open-circuit voltage, 5,8,16,18,20,21,24,34,35,39,44,[47][48][49] short-circuit current, 5,8,10,11,16,18,20,21,24,34,35,39,…”

Mechanism of In-Plane and Out-of-Plane Tribovoltaic Direct-Current Transport with a Metal/Oxide/Metal Dynamic Heterojunction

“…Sustainable energy solutions remain as a major challenge for miniaturized and distributed intelligent devices as the new era of internet of things has come of age. − Among green energy harvesting technologies, mechanical energy harvesting via dynamic Schottky or P–N junction-based direct-current (DC) generators is emerging as one of the most promising strategies by virtue of their exceptional advantages on high current density ( J , 10–100 A m –2 , 3–4 orders higher than that of traditional triboelectric nanogenerators or piezoelectric nanogenerators) due to low impedance, consistent efficiency at low frequency of motion (<10 Hz), and free of power rectification. − Heretofore, considerable research efforts have been devoted to understand the mechanism of the DC generation phenomenon, as well as to explore various material schemes including 2D materials, ,− oxides, perovskites, , conducting polymers, − silicon, − and liquid–semiconductor junctions , for enhanced DC output. Despite the large short-circuit current ( I SC ) output, the relatively low intrinsic open-circuit voltage ( V OC , hundreds of millivolts) in DC generators has hindered their implementation for practical use.…”