本次研究以陽極氧化法搭配水熱法來製備n型半導體氮化鉭產氧電極，藉由X光繞射儀以及掃描式電子顯微鏡分析，發現其結構仍為斜方晶相奈米顆粒，並由這些奈米顆粒組成較大且具有階層狀孔洞之立方顆粒，另外，利用鈷元素的摻雜，氮化鉭電極能大幅提升光電流，這是由於內部形成p-n電場而改善電荷分離，減少電荷再結合發生，使得其光電化學反應之效能提升。
與一般陽極氧化法所製備出的氮化鉭電極不同，此結構具有孔洞的存在，因此能夠增加觸媒之表面積，但由於所形成的立方顆粒偏大，整體結構不夠緻密且內部的連結性不佳，對於電荷的傳導有較大阻礙，因此為了能夠進一步改善此情況，利用氯化鉭溶液進行後處理來增加顆粒間的連接性，使顆粒間的緻密度提高，因此能夠減低電荷傳遞時的阻力，增加光電流的效果。
而在光電化學測試中，主要以三極式的系統中進行反應，並且以太陽模擬光AM 1.5 G照射下，0.5 M的氫氧化鉀水溶液中，結果顯示具備階層狀孔洞之氮化鉭電極在經過後處理及鈷摻雜後，所呈現之光電流效能於偏壓0.5 V vs. Ag/AgCl下可達到3.6 mA/cm2，其效能遠高於純粹氮化鉭電極。

In the present work, a new method combining anodization and hydrothermal method is used to fabricate a n-type semiconductor cubic tantalum nitride(C-Ta3N5) electrode. From XRD and SEM analysis, which can know that C-Ta3N5 belong to orthorhombic phase, and has larger size of cubic particles with the hierarchical porous structure made up of Ta3N5 nanoparticles. Besides, the Co element doping of cubic tantalum nitride(C-Ta3N5:Co) electrode can significantly increase photocurrent by the built-in p-n junction which helps for charge separation and reduces the charge recombination. Therefore, the performance can be strongly enhanced.
Different form general anodization method, the new method can synthesize cubic tantalum nitride(C-Ta3N5) electrode with pores increasing the surface area. However, the cubic particles are quit large leading to bad charge transfer because the whole structure is not compact enough and rare connection between particles. To improve this situation, the tantalum chloride solution is used for post-treatment to increase the connection of particles and make them more compact. During the photoelectrochemical test conducting in three-electrode system under AM 1.5 G simulated sunlight illumination, the photocurrent density of C-Ta3N5:Co can reach 3.6 mA/cm2, which is much higher than bare Ta3N5 electrode at 0.5 V vs. Ag/AgCl in 0.5M KOH solution.

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