The photoelectrochemical (PEC) process is one of the most promising techniques for converting solar energy directly into clean fuels and for environmental remediation applications. One-dimensional (1D) TiO₂ nanostructure arrays are extensively studied morphologies for a wide variety of catalytic processes, including photocatalysis (PC) and PEC reactions for water splitting. In this study, well-aligned TiO₂ nanorod (TNR) arrays were uniformly grown on a fluorine-doped tin oxide substrate, and thermal exfoliation of the TNRs, which appeared as small islands, was investigated. The calcination time, which ranged from 1 to 5 h at 400 °C, had a significant impact on the agglomerated TNRs islands, which tended to be uniformly exfoliated as spaced nanorods and eventually improved the PEC current density. The regularly arranged spaced nanorods allow for the efficient transfer of internal charge carriers within the TNRs. Furthermore, the heterojunction formation with NiCo₂S₄ via the successive ionic layer adsorption and reaction (SILAR) method, results improved PEC performance, owing to reduced charge carrier recombination at the interface of the heterojunction. The Mott–Schottky analysis strongly supports the improved charge carrier density at the heterojunction interface. The improved life time of the charge carriers was investigated by comparing the time-resolved photoluminescence spectra for the TiO₂/NiCo₂S₄ heterojunction with pristine TNRs, which was eventually confirmed by incident photon-to-current efficiency analysis.

光电化学 (PEC) 工艺是将太阳能直接转化为清洁燃料和用于环境修复应用的最有前途的技术之一。一维 (1D) TiO ₂纳米结构阵列被广泛研究用于各种催化过程的形态，包括用于水分解的光催化 (PC) 和 PEC 反应。在本研究中，排列良好的 TiO ₂纳米棒 (TNR) 阵列均匀地生长在掺氟的氧化锡衬底上，并研究了 TNR 的热剥落，其表现为小岛。400°C 下 1 至 5 小时的煅烧时间对聚集的 TNRs 岛有显着影响，TNRs 岛倾向于均匀剥离为间隔纳米棒并最终提高 PEC 电流密度。规则排列的间隔纳米棒允许内部电荷载流子在 TNR 内有效转移。此外，与 NiCo ₂ S ₄形成异质结通过连续离子层吸附和反应 (SILAR) 方法，由于异质结界面处的电荷载流子复合减少，因此提高了 PEC 性能。Mott-Schottky 分析强烈支持异质结界面处电荷载流子密度的提高。通过将 TiO ₂ /NiCo ₂ S ₄异质结的时间分辨光致发光光谱与原始 TNR进行比较，研究了电荷载流子寿命的延长，这最终通过入射光子到电流效率分析得到证实。