| Triboelectrification can be said to be ubiquitous in nature.In daily life,all kinds of objects may generate static due to movement or triboelectrification.However,triboelectric effect has always been considered as a negative effect that will cause harm to human productive activity and life.In fact,with the deeper insights and knowledge,this effect has gradually been used by humans.Based on the coupling effects of triboelectrification and electrostatic induction,triboelectric nanogenerator?TENG?was first put forward in 2012,which could effectively convert the mechanical energy that was prevalent in everyday life but often wasted into electricity.Therefore,TENGs have been applied in many fields of self-powered gas-sensing system,blue energy,wearable electronic devices etc.In addition,TENGs could be widely implemented in different systems because of the advantages of wide selection of materials,light weight,low cost and much categories.More importantly,in view of its high voltage and low current output characteristics,TENG has become a new choice as portable high-voltage power sources with high security.In order to make full use of the advantage and high-voltage output performance of TENGs,more extensive and thorough research is imperative.The research contents of this paper are summarised as follows:First,a rotatory disc-shaped TENG?RD-TENG?was prepared.Polytetrafluoroethylene?PTFE?film with single-sided viscosity and good abrasion resistance was selected as the triboelec-layer,and the performance of TENG was improved by surface modification of the PTFE film.Under various rotation speeds,the value of Voc is kept at230 V without obvious change,and Isc increases as the speed raises,and the peak current reaches 0.12 mA at 140 rpm.After the transformation by a transformer,the output parameters of the RD-TENG,mainly Voc and Isc,rise simultaneously with increasing the speed of rotation.The peak voltage and corresponding peak current increase to11 V and 1.6 mA,respectively,at the speed of140 rpm.The RD-TENG can provide a DC output of low-voltage and high-current.In addition,the output of RD-TENG can be changed by adjusting the rotation speed that to supply energy for different systems.Second,a hybridized mechanical and solar energies driven self-powered hydrogen production system was established.RD-TENG was employed to harvest mechanical energy from water and functions as a sufficient external power source.WO3/BiVO4heterojunction photoanode was synthesized in a photoelectrochemical?PEC?water splitting cell to produce H2.After transformation and rectification,the peak current reaches 0.1 mA at the rotation speed of 60 rpm.In this case,the H2 evolution process only occurs with sunlight irradiation.When the rotation speed is over 130 rpm,the peak photocurrent and peak dark current have nearly equal value.Direct electrolysis of water is almost simultaneous with photoelectrocatalysis of water.It is worth noting that the hydrogen production rate increases to 5.45?L/min and 7.27?L/min without or with light illumination at 160 rpm.The corresponding energy conversion efficiency is calculated to be 2.46%and 2.61%,respectively.Such a self-powered system can successfully achieve PEC hydrogen generation,which provides an effective method for obtaining hydrogen energy.Third,a TENG driven electric stimulation system has been designed for biosafety evaluation and exploration of the fibroblast cell behaviors.RD-TENG was fabricated to obtain an adjustable range of alternating current outputs.The peak current generated in a range of 10–50?A is suitable for promoting cellular proliferation behavior of L929cells.At the optimum value of 50?A,the promotion rate reached 53.8±2.66%after two-day of intermittent stimulation.Also,the migration rate increased by about 67%than those in the control group.In addition,under stimulation,the proliferation-related gene of L929 cells-Pcna and the two migration-related genes-Fgf2 and Dlk1 were also found up-regulated,suggesting that TENG stimulation regulates cell proliferation and migration at the level of gene expression.The present study demonstrates the effectiveness of TENG and its safe operation conditions in biomedical stimulation,which lays the foundation for practical application of TENG on tissue formation,reepithelialization and tissue remodeling.There are 156 references,8 tables and 46 figures in this paper. |
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