Study On Betavoltaic Effect Based On Electrochemical Reduction Of TiO₂ Nanotube Arrays

In extreme environments such as the polar regions and deep seas,conventional power supplies can not provide high-stability and long-life power supplies for microelectronic devices.Betavoltaic cell has become the focus in the field of microenergy research due to its long service life,high integration and high energy density.Currently,the energy conversion efficiency(ECE)of betavoltaic cells is generally low.Therefore,how to improve the ECE of betavoltaic cells has always been a research hotspot.In this paper,titanium dioxide nanotube arrays(TNTAs)were used as energy conversion materials,using 1VNi isotope radiation sources to assemble betavoltaic cells.The research content mainly included the growth and characterization of TNTAs,electrochemical reduction of TNTAs film,fullerene(C60)surface modification of TNTAs,electrical tests of betavoltaic cells based on electrochemical reduction of TNTAs,and performance tests of ultraviolet light detectors based on electrochemical reduction of TNTAs.The TNTAs consisted of compacted and highly ordered cylindrical nanotubes with uniform pore diameter of around 100 nm and tube-wall thickness of around 10 nm,and TNTAs were characterized by FESEM,XRD,ESR and other test systems.A 20 mCi of 63Ni betavoltaic cell based on the reduced TNTAs exhibited maximum ECE of 5.54%with open-circuit voltage of 0.67 V,short-circuit current of 352.32 nA.Then using TNTAs sample modified by the C60,the betavoltaic effect was improved.Betavoltaic cell based on the improved TNTAs exhibited maximum ECE of 5.83%with open-circuit voltage of 0.86 V,short-circuit current of 274.16 nA.Finally,the photogenerated currents generated by ultraviolet light detectors based on different TNTAs samples under different power or different frequencies of ultraviolet light were compared.Under the ultraviolet light with a power of 3.00 mW cm-2,the device showed the best.The light response performance exhibited a photoresponse current density of 117.2 μA cm-2 and a light responsivity of 39.1 mA W-1.This study shows that the wide band gap TNTAs after electrochemical reduction can be used as the transducing material for betavoltaic cell,which can significantly improve the ECE of betavoltaic cell.The use of improved TNTAs modified by C60 further improves the ECE of the betavoltaic cell.At the same time,in the field of photodetection,ultraviolet detectors based on electrochemical reduction of TNTAs also exhibit excellent photoresponsive performance.Therefore,the betavoltaic cell based on electrochemical reduction of TNTAs is a viable and effective micro-energy solution.