A two-step anodization method was used to prepare an efficient nano Ti electrode (ENTE), based on the nano Ti electrode (NTE) that was synthesized by the traditional anodization method. The result of FESEM showed there were many nanopores and nanoparticles on the surface of the ENTE. Compared with Ti electrode, the ENTE exhibited an increased electrochemical activity of nitrate reduction, attributing to its ∼1.09-fold higher reduction peak current density. Values of average current efficiency towards nitrate reduction indicated that the electrochemical properties of different electrodes were raised in the order of ENTE (0.36) > NTE (0.25) > Ti electrode (0.15). The ENTE exhibited a ∼3.33-fold higher electroactive surface area than that of Ti electrode. The higher current density throughout the 1000 s and the ∼1.27-fold higher final current density at 1000 s suggested that the ENTE had a higher stability for nitrate electroreduction. The nitrate reduction efficiency increased with the increasing of initial nitrate-nitrogen concentration and temperature. Similar effect was obtained from current density below 50 mA cm⁻². And under the neutral condition, a higher nitrate reduction efficiency was achieved. The curved surface and higher surface area due to the nanopores of the ENTE increased the nitrate concentration in the EDL and enhanced the potential of individual nitrate ions in the diffuse layer exponentially. This research provided a new route to assess a nano-electrode with high stability and a clear reaction mechanism in EDL.

基于传统的阳极氧化方法合成的纳米钛电极（NTE），采用了两步阳极氧化方法来制备高效的纳米钛电极（ENTE）。FESEM的结果表明，在ENTE的表面上有许多纳米孔和纳米颗粒。与Ti电极相比，ENTE的硝酸盐还原电化学活性更高，归因于其还原峰电流密度高约1.09倍。硝酸盐还原的平均电流效率值表明，不同电极的电化学性能按ENTE（0.36）> NTE（0.25）> Ti电极（0.15）的顺序提高。ENTE的电活性表面积比Ti电极高约3.33倍。在1000 s和〜1的时间内有较高的电流密度。最终电流密度在1000 s时提高了27倍，这表明ENTE对硝酸盐的电还原具有更高的稳定性。硝酸盐还原效率随初始硝酸盐氮浓度和温度的升高而增加。从低于50 mA cm的电流密度获得类似的效果⁻²。在中性条件下，硝酸盐还原效率更高。由于ENTE的纳米孔而导致的弯曲表面和较高的表面积增加了EDL中的硝酸盐浓度，并以扩散方式指数地增加了扩散层中各个硝酸根离子的电势。该研究为评估EDL中具有高稳定性和明确反应机理的纳米电极提供了一条新途径。