本研究在探討關鍵性電化學與光電化學的電極儲能材料，研究目標有三： (1)依Pechini法合成Ruddlesden-Popper (RP)結構之RP-LaSr3Fe3-xMxO10(MX = Co0~1.5或Mn0~0.5)錳鈷摻雜物，並探討其對氧還原反應 (Oxygen reduction reaction, ORR) 與氧氣釋出反應 (Oxygen evolution reaction, OER)之催化活性。(2) 以簡單之沉積退火法(Deposition-Annealing method, DA)，探討製備赤鐵礦製程參數，以獲致最佳光陽極之條件。(3) 結合第(1)、(2)技術，將RP-LaSr3Fe3-xMxO10裝載於最佳赤鐵礦製備光陽極，探討是否會增進光電化學分解水之效率。 結果顯示： (1) RP-LaSr3Fe3-xMxO10(M = Co, Mn)之ORR/OER催化活性高於純RP-LaSr3Fe3O10，摻鈷之樣品效率更高於摻錳者，尤其摻鈷量在x=1.5催化活性最高，在定電流ORR(3 mA/cm2 )/OER(10 mA/cm2)下之電位差值(ΔE) 約為0.93 V，比文獻值(1.00 V~1.16V)小，顯示雙催化效率更極佳。(2) 以前驅物在5 mM進行10次沉積退火(即10 DA)所得之赤鐵礦光陽極，其光暗差電流最佳(即照光電流-暗室電流)，可達6.3 mA/cm2。 (3) 裝載RP-LaSr3Fe1.5Co1.5O10之赤鐵礦光陽極，可藉RP-LaSr3Fe1.5Co1.5O10提升OER催化效率，因而增進光陽極之水分解效率，光暗差之電流提升約108%。 ;This study facilitated the design of critical element for clean energy-conversion and energy-storage electrode material. The main three goals of research were as follow, (1) we attempted to fabricate the RP-LaSr3Fe3-xMxO10 with B-site cations substitution with Mn and Co via Pechini method. Effects of B-site cation kinds and components on the catalytic property for ORR/OER of RP-LaSr3Fe3-xMxO10 were investigated; (2) the α-Fe2O3 photoanode were fabricated on F-doped SnO2 glass substrate via a facile Deposition-Annealing (DA) process. Influence of synthetic parameters on photoelectrochemical performance of α-Fe2O3 photoanodes were characterization; (3) with above technique on electrode, heterojunction of RP-LaSr3Fe3O10/α-Fe2O3 were carried out which facilitated a enhancement for photoelectrochemical water splitting. The developmental results were summarized below: (1) RP-LaSr3Fe1.5Co1.5O10 revealed a higher ORR/OER catalytic activity than other B-site cation kinds or components. The different in potential between the ORR at 3 mA/cm2 and the OER at 10 mA/cm2 was measured (ΔE =0.93 V), which was lower than data reported elsewhere demonstrating high bifunctional catalytic avtivity. (2) Result from the synthesis of α-Fe2O3, the sample prepared via 5 mM precusor and 10 DA cycles had better physical and chemical properties than synthetic parameters. The maximum photocurrent could reach 6.3 mA/cm2. (3) The modification of the RP-LaSr3Fe1.5Co1.5O10/hematite heterojunction photoanodes facilitated the electron transfer at the electrode/electrolyte interface and thus enhanced the 108% of efficient on photoelectrochemical water splitting. Compared to noble material, RP-LaSr3Fe3-xMxO10 have been employed for the synthesis of the heterojunction photoanodes via a simple route. The photoelectrochemical results have great important, both from scientific and an economical point of view.
