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“The amount of antidepressants consumed globally each year is much larger than what most people imagine. ”A selective serotonin reuptake inhibitor named fluoxetine (commonly known as Prozac), due to its widespread prescription around the world, has been continuously detected in wastewater effluents and surface waters across various countries, with concentrations reaching up to 0.5 micrograms per liter. Although this figure seems small, its impact on aquatic ecosystems cannot be underestimated. The crux of the problem is that fluoxetine has extremely high environmental persistence. It is resistant to hydrolysis as well as difficult to be degraded by microorganisms; less than 10% of it is metabolized in the human body after oral administration, with a large amount of the original substance entering wastewater treatment systems via feces, and existing conventional treatment processes are almost ineffective against it. In other words, these trace pollutants manage to pass through all the filters in wastewater treatment plants and end up in natural water bodies, accumulating there silently over year after year. There is one detail worth noting here: the issue with fluoxetine is essentially a process in which a \"regulatory gap\" is being gradually illuminated by the scientific community. Previously, the formulation of wastewater treatment standards in various countries focused primarily on traditional indicators such as heavy metals, ammonia nitrogen, and COD, with relatively little attention paid to pharmacologically active compounds (PhACs). The reality is that emerging pollutants like fluoxetine continue to enter water bodies in ways that are invisible to the naked eye, silently affecting fish endocrine systems as well as the entire food chain. This is not an exaggeration, but an objective trend repeatedly confirmed by water quality monitoring data from various countries. This entrenched situation is forcing the water treatment industry to seek more targeted technical solutions. The electrochemical oxidation method (EO) is an efficient technique that has emerged against this backdrop. Its core principle is to use electrical energy as a driving force; hydroxyl radicals are generated at the anode, which directly mineralize and degrade organic pollutants, completely destroying their molecular structure. Compared with traditional biological treatment, electrochemical oxidation requires no chemical reagents, occupies less space, and is flexible in operation; it is particularly effective against those stubbornly difficult-to-degrade organic substances. For this reason, the application prospects of this technology in the treatment of pharmaceutical wastewater and fine chemical wastewater are attracting increasing attention. In February 2025, a research team from Ildiz Technical University in Turkey published a highly valuable study in the journal Sigma: Journal of Engineering and Natural Sciences. Using fluoxetine as the target pollutant, they systematically compared the performance of three different size-stable anodes (DSA) with coatings during electrochemical oxidation: a ruthenium oxide-coated anode (Ti/RuO₂), an iridium-tantalum oxide-coated anode (Ti/IrO₂-Ta₂O₅), and an iridium/ruthenium/tin composite oxide-coated anode (Ti/Ir-Ru-Sn), with graphite electrodes being used as the cathode in all cases. The experiment was conducted under strictly controlled batch conditions, and the researchers examined one by one the effects of current intensity, solution pH, oxidation time, and the initial concentration of fluoxetine on the removal efficiency. The results showed that at pH 7, with a current of 2 A and a fluoxetine concentration of 20 mg/L, all three anodes achieved a removal rate of 99.9% in just 20 minutes. What does this number mean? It means almost complete removal—a level that far exceeds that of many traditional treatment processes. Of particular note, the Ti/IrO₂-Ta₂O₅ anode achieved the lowest specific energy consumption (SEC) at both 10 and 20 minutes, and maintained a removal efficiency of nearly 100% across all test concentration ranges from 5 to 40 mg/L. It is necessary to mention here something that is rarely discussed openly within the industry: the selection of electrode materials essentially involves finding a balance between \"processing efficiency\" and \"operational costs\". Many system integrators focus only on the purchase price when making their selections, ignoring the decisive impact of electrode life and energy consumption per unit on the total lifecycle cost. An electrode that appears inexpensive may need to be replaced every few months due to corrosion or passivation, and the increased energy consumption resulting from reduced efficiency means that, in the long run, it is not a cost-effective solution. In contrast, electrodes with a tantalum coating have a relatively higher initial cost, but thanks to their excellent chemical stability and consistent low energy consumption, they tend to offer better economic benefits over the long-term operational period. This selection logic of focusing on the long term rather than the short term is gradually gaining acceptance among customers in the fine chemicals and pharmaceutical chemicals sectors. Tantalum oxide (Ta₂O₅), as a component of the coating, is by no means a secondary element; rather, it is one of the key factors determining the overall performance of the electrode. Tantalum is renowned for its extremely high chemical stability – it performs excellently in strong acids, strong bases, and even under high-temperature oxidation conditions. Its melting point is around 2996°C, and the dense Ta₂O₅ oxide layer that forms naturally on its surface grants it outstanding self-passivating corrosion resistance. It is this stability that enables tantalum-based coated anodes to operate stably over long periods in harsh electrochemical environments, without failing prematurely due to medium erosion, thus allowing the oxidation reaction to take place at lower voltage losses – and this is the fundamental reason for their energy efficiency advantage. It is worth further consideration that the significance of this study is not limited to fluoxetine as the only pollutant. Electrochemical oxidation is itself a platform technology with wide applicability to a range of difficult-to-degrade micropollutants, including halogenated organic compounds, endocrine disruptors, and antibiotics. The combination of high efficiency and low energy consumption demonstrated by tantalum-based electrodes in this study indicates that they have the potential to become core components in future high-standard industrial wastewater treatment systems, rather than merely being a preferred option for laboratory use. Tantalum, a metal that has long been used in high-end fields such as aviation, chemical equipment, and medical devices, is now finding new applications in the field of environmental water treatment. As countries continue to tighten regulatory standards for emerging pollutants and raise requirements for industrial emissions, the demand for such high-performance, long-lasting electrode materials will only increase over time. 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