npj Clean WaterPub Date : 2025-07-01DOI: 10.1038/s41545-025-00488-w
Zhi Gao, Yu-Lei Liu, Zhuang-Song Huang, Xiao-Na Zhao, Xian-Shi Wang, Zi-Yi Han, Chong-Wei Cui, Jun Ma, Lu Wang
{"title":"Tailoring Fe(VI) coordination microenvironment for high-efficiency oxidation: ligand-driven electron transfer and polymerization steering","authors":"Zhi Gao, Yu-Lei Liu, Zhuang-Song Huang, Xiao-Na Zhao, Xian-Shi Wang, Zi-Yi Han, Chong-Wei Cui, Jun Ma, Lu Wang","doi":"10.1038/s41545-025-00488-w","DOIUrl":"https://doi.org/10.1038/s41545-025-00488-w","url":null,"abstract":"<p>Utilizing ligand-mediated homogeneous catalysis to enhance oxidant-driven pollutant removal efficiency presents significant research value while posing substantial challenges. This study utilized ethylenediaminetetraacetic acid (EDTA) to alter the coordination environment of ferrate(VI), thereby steering electron transfer and the phenoxylation pathways to enhance the pollutant removal, which is realized by the complexation-mediated regulation for kinetics and thermodynamics. For example, the introduction of EDTA increased the rate constant of ferrate(VI) oxidizing phenol by four times (from 50.79 M<sup>−1</sup> s<sup>−1</sup> to 208 M<sup>−1</sup> s<sup>−1</sup>) and the stoichiometric ratio (∆[phenol]/∆[K<sub>2</sub>FeO<sub>4</sub>]) from 0.17:1 to 0.22:1. Theoretical calculation and experimental characterization proved that the in-situ formed metastable Fe(VI)-EDTA complex facilitates the electron transfer from Fe(VI) to benzene ring and the phenoxylation pathways. Consequently, the related polymerization products were produced in greater quantities (about 5 times) and with broader diversity than Fe(VI) alone. In the application to real water, the introduction of EDTA reduced more than half of ferrate(VI)’s dosage previously required for completely removing phenol. This study presents a novel strategy for optimizing ferrate(VI) oxidizing pollutants in water treatment, which presents notable environmental benefits by minimizing ferrate(VI) consumption and enhancing pollutant removal efficiency.</p><figure></figure>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"36 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144520861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj Clean WaterPub Date : 2025-06-15DOI: 10.1038/s41545-025-00490-2
Jun-U Jang, Jeongmi Park, Hyunjung Kim, Seonki Lee, Kwang-Ho Choo, Kibaek Lee
{"title":"Harnessing gravity-driven membranes in activated sludge bioreactors: Enhancing energy efficiency and mitigating biofouling via quorum quenching","authors":"Jun-U Jang, Jeongmi Park, Hyunjung Kim, Seonki Lee, Kwang-Ho Choo, Kibaek Lee","doi":"10.1038/s41545-025-00490-2","DOIUrl":"https://doi.org/10.1038/s41545-025-00490-2","url":null,"abstract":"<p>This study developed a gravity-driven membrane bioreactor (GD-MBR) to reduce energy consumption in wastewater treatment. The system maintained a stable flux of 6 L/m<sup>2</sup>/h when treating high-organic wastewater loads (TOC: 270 mg/L, SS: 7,000 mg/L), surpassing conventional GDMs (2–4 L/m²/h). Quorum quenching (QQ) extended stable flux duration and increased cumulative permeate volume by 26%, treating 130 L and 73 L over 65 and 35 days, respectively, compared to 105 L and 50 L in the non-QQ system. QQ reduced biofilm extracellular polymeric substances (polysaccharides by 30% and proteins by 20%) and significantly lowered <i>N</i>-acylhomoserine lactone concentrations (e.g., C8-HSL: 0.02 ± 0.01 pM vs. 0.34 ± 0.03 pM after 106 days). Next-generation sequencing showed increased microbial network complexity (edges: 32 vs. 27) and downregulation of biofilm- and quorum-sensing-related genes (HigA-1, Fis, LuxR family). These results highlight the potential of QQ-enhanced GD-MBRs for energy-efficient treatment of high-organic wastewater loads.</p><figure></figure>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"31 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144290229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Photothermal-assisted cleaning and reusability of MXene-MWCNT membranes for efficient oil–water separation","authors":"Siyoung Byun, Dongjin Sim, Alicia Kyoungjin An, Eui-jong Lee, Jae-Wuk Koo, Tae-Mun Hwang, Sanghyun Jeong","doi":"10.1038/s41545-025-00485-z","DOIUrl":"https://doi.org/10.1038/s41545-025-00485-z","url":null,"abstract":"<p>Membrane-based separation can efficiently treat oily wastewater; however, the trade-off between flux and oil rejection, as well as susceptibility to oil fouling, particularly when dealing with highly viscous oils, often limits its applicability. To address these limitations, MXene-multi-walled carbon nanotube (MWCNT) composite membranes were fabricated, exhibiting improved permeate flux and anti-fouling performance. The fabricated MXene-MWCNT membrane showed an oil emulsion permeate flux exceeding 19 L/m²∙h (LMH), along with a high oil rejection efficiency (~95%), effectively mitigating the conventional trade-offs associated with membrane-based separations. However, the membrane was susceptible to irreversible oil fouling when exposed to highly viscous oils, thus challenging sustainable operation. To overcome this issue, a photothermal-assisted cleaning strategy was employed. This approach enhances localized photothermal heating to reduce fouling and enhance membrane reusability. The MXene-MWCNT membrane maintained an adequate flux recovery rate (>60%) and a stable oil rejection efficiency (~99%) over four operational cycles. In comparison, membranes without photothermal cleaning achieved a flux recovery of only ~7% under similar conditions. Given its high permeate flux, excellent oil rejection performance, and enhanced anti-fouling properties achieved <i>via</i> photothermal-assisted cleaning, the MXene-MWCNT membrane offers a sustainable and effective solution for practical oil–water separation applications, particularly when treating wastewater containing highly viscous oils.</p>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"593 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144288423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Review of the emerging technologies in the water sector with a focus on the deployment of Internet of Things solutions","authors":"Patrick Ouma Obunga, Sophia Sudi Rwanga, Megersa Olumana Dinka, Benton Onyango Otieno","doi":"10.1038/s41545-025-00487-x","DOIUrl":"https://doi.org/10.1038/s41545-025-00487-x","url":null,"abstract":"<p>The study focused on identification of Internet of Things (IoT) solutions that can be used in the management of non-revenue water (NRW) in water distribution networks (WDN). The review show that water utilities incur significant revenue losses due to NRW emanating from leaks, illegal connections, and non-payment of water bills. The uptake, adoption, and deployment of IoT solutions can contribute to the realization of new products and services, sustainable development solutions, transformation, and enhanced decision-making, in the water sector. Overally, IoT solutions can help water utilities improve operations and management of WDN and minimize NRW, which aligns with the anticipated impact of the study on contributing to and enhancing the realization of resilient smart cities. Finally, the novelty of the study is to demonstrate the potential of translating theoretical innovations and technologies into industrial/ practical applications and commercialization.</p>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"8 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144288431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj Clean WaterPub Date : 2025-06-12DOI: 10.1038/s41545-025-00484-0
Ali Jalili, Georgios Kolliopoulos
{"title":"A review of fundamentals, challenges, prospects, and emerging trends in hydrate-based desalination","authors":"Ali Jalili, Georgios Kolliopoulos","doi":"10.1038/s41545-025-00484-0","DOIUrl":"https://doi.org/10.1038/s41545-025-00484-0","url":null,"abstract":"<p>Hydrate-based desalination (HBD) has emerged as a promising technology among conventional desalination methods due to its low energy consumption, wide operating window with regards to total dissolved solids (TDS), and efficient water recovery. This paper provides an in-depth review of the fundamental properties of hydrates, including thermodynamic and kinetic aspects of their formation. Then, it delves into recent advancements in thermodynamic and kinetic hydrate promoters that aim to address HBD’s main challenge, which is the slow hydrate formation process. Subsequently, the review systematically examines environmental and toxicity concerns associated with chemicals used in HBD, addressing the growing demand for sustainable and biodegradable desalination solutions. Finally, a comparative analysis between HBD and conventional methods highlights its potential as an energy-efficient and selective desalination process poised to enhance sustainability within the water-energy-environment nexus.</p><figure></figure>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"64 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144268893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj Clean WaterPub Date : 2025-06-10DOI: 10.1038/s41545-025-00486-y
Josue Yaedalm Son, Yeseul Jo, Hyeran Lee, Youn Jeong Jang, Hyejeong Kim
{"title":"Water hyacinth-inspired self-floating photocatalytic system for efficient and sustainable water purification","authors":"Josue Yaedalm Son, Yeseul Jo, Hyeran Lee, Youn Jeong Jang, Hyejeong Kim","doi":"10.1038/s41545-025-00486-y","DOIUrl":"https://doi.org/10.1038/s41545-025-00486-y","url":null,"abstract":"<p>Photocatalytic water remediation is an effective approach for wastewater treatment; however, conventional powdered photocatalysts face challenges, including agglomeration, difficult separation, and inefficient light utilization due to their tendency to sink in water. Inspired by the buoyancy and water purification ability of water hyacinth, a self-floating photocatalytic system, Water Hyacinth-Inspired Purifier (WHIP), was developed by integrating TiO<sub>2</sub> photocatalysts onto a porous polydimethylsiloxane substrate, with a central closed-pore structure mimicking the sponge tissue of water hyacinth. This biomimetic design ensures stable flotation under static and dynamic flow conditions, maximizing light exposure for efficient photocatalysis. WHIP effectively degraded various contaminants, including methylene blue (99.5 ± 0.4%), rhodamine 6G (98.6 ± 1.5%), methyl orange (72.6 ± 6.4%), and nanoplastics. To assess its scalability and versatility, a large-scale WHIP incorporating a TiO<sub>2</sub>/graphdiyne photocatalyst was fabricated, achieving 94.9% methylene blue removal under real ambient conditions. These findings highlight WHIP’s potential as a sustainable environmental remediation technology.</p>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"24 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144260176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
npj Clean WaterPub Date : 2025-06-03DOI: 10.1038/s41545-025-00483-1
Velu Manikandan, Duraisamy Elango, Velu Subash, Ponnuchamy Kumar, Jeyakumar Saranya Packialakshmi, Palaniyappan Jayanthi, You Jae Sun, Kwang Soup Song
{"title":"Needle ZrOx loaded NiFe2O4 catalysts for Photo-Fenton degradation of bisphenol A and 4 nitrophenol","authors":"Velu Manikandan, Duraisamy Elango, Velu Subash, Ponnuchamy Kumar, Jeyakumar Saranya Packialakshmi, Palaniyappan Jayanthi, You Jae Sun, Kwang Soup Song","doi":"10.1038/s41545-025-00483-1","DOIUrl":"https://doi.org/10.1038/s41545-025-00483-1","url":null,"abstract":"<p>This study investigates the synthesis of ZrO<sub><i>x</i></sub>-loaded NiFe<sub>2</sub>O<sub>4</sub> photocatalysts (1, 2, and 3 wt%) through co-precipitation and wet impregnation methods for environmental and health applications. The structural analysis revealed a cubic crystal structure, with ZrO<sub><i>x</i></sub> doping enhancing charge separation and mobility by converting the morphology from fibrous to needle-like. Under visible light (VL) and H<sub>2</sub>O<sub>2</sub> activation, the ZrO<sub><i>x</i></sub>(3 wt%)/NiFe<sub>2</sub>O<sub>4</sub> composite achieved high degradation efficiencies (98.5% for Bisphenol A and 98.2% for 4-Nitrophenol) in 120 min via the Photo-Fenton mechanism. Kinetic analysis showed pseudo-first-order behavior with rate constants of 0.945 min<sup>−1</sup> for BPA and 0.904 min<sup>−1</sup> for 4-NP. The catalyst demonstrated stability with 91.5% efficiency retention after multiple cycles. DFT calculations indicated favorable HOMO-LUMO alignments and electrostatic potentials. Additionally, ZrO<sub><i>x</i></sub>(3 wt%)/NiFe<sub>2</sub>O<sub>4</sub> exhibited selective cytotoxicity against breast cancer cell lines, while maintaining high viability in HEK-293 cells. The results suggest that ZrO<sub><i>x</i></sub>(3 wt%)/NiFe<sub>2</sub>O<sub>4</sub> composites are promising for environmental and biomedical applications.</p><figure></figure>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"30 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144202049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Natural and anthropogenic imprints on seasonal river water quality trends across China","authors":"Haoran Zhang, Huihang Sun, Jiarong Li, Yuelei Li, Luyu Zhang, Ruikun Zhao, Xiangang Hu, Nanqi Ren, Yu Tian","doi":"10.1038/s41545-025-00481-3","DOIUrl":"https://doi.org/10.1038/s41545-025-00481-3","url":null,"abstract":"<p>Climate change and human activities have redefined seasonal river water quality patterns, yet their respective impacts remain unclear. Here, we propose a novel trend-based metric, the T-NM index, to isolate asymmetric human amplification and suppression effects across 195 natural and 1540 managed watersheds in China (2006–2020). Consistent trends in 52–89% of watersheds suggest climatic dominance, while anthropogenic drivers intensified or attenuated trends by 22–158% and 14–56%, especially in summer. Four independent multivariable models simulated seasonal COD and DO concentrations. Attribution analysis showed that seasonal factors explained 47.08% of the variation, while rainfall (25.37%) and slope (17.40%) accounted for COD and DO changes in natural watersheds; in contrast, Shannon Diversity Index (11.58%) and Largest Patch Index (10.66%) dominated in managed watersheds. This study establishes a generalizable framework for distinguishing natural and anthropogenic influences, offering key insights for adaptive water quality management under future climatic and socio-economic transitions.</p>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"9 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144202050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing photocatalytic efficiency through surface modification to manipulate internal electron-hole distribution","authors":"Hong Tu, Bihong Tian, Shunshun Chen, Jingyi Xu, Jianrong Yang, Zhichao Zhao, Shunhong Chen, Jian Wu","doi":"10.1038/s41545-025-00480-4","DOIUrl":"https://doi.org/10.1038/s41545-025-00480-4","url":null,"abstract":"<p>In this study, we synthesized ten g-C<sub>3</sub>N<sub>4</sub>-based covalent organic frameworks (COFs) and identified CN-306 as the most effective catalyst for visible-light-driven hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) production. Systematic optimization revealed that increasing ethanol proportions in the reaction medium significantly enhanced H<sub>2</sub>O<sub>2</sub> yield, achieving a remarkable production rate of 5352 μmol g<sup>−1</sup>h<sup>−1</sup> with a surface quantum efficiency of 7.27% at λ = 420 nm. Intriguingly, mechanistic investigations uncovered that excessive generation of singlet oxygen (<sup>1</sup>O<sub>2</sub>) acts as a critical inhibitory factor, impeding H<sub>2</sub>O<sub>2</sub> accumulation. Multimodal characterization techniques combined with density functional theory (DFT) calculations were employed to unravel the origin of CN-306’s superior performance. Theoretical analyses demonstrated that CN-306 exhibits enhanced electron-hole separation efficiency, attributed to its reduced energy gap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO), which facilitates photocarrier migration and suppresses detrimental recombination. Furthermore, this work elucidates the structure-function relationships governing site-specific functional group modifications in COFs and their profound influence on photocatalytic activity. These findings provide molecular-level insights into rational catalyst design for optimizing surface structures and advancing solar-driven H<sub>2</sub>O<sub>2</sub> synthesis applications.</p>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"1 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144176759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Scalable, high-efficiency porous monolithic polymer foam for solar-driven interfacial water evaporation and lithium extraction","authors":"Chunyang Jiang, Ziyi Yan, Yuefeng Bai, Ruoxin Li, Mingrui Wu, Wen-Hao Yu, Hong-Mei Chen, Ping Hu, Ke-Qin Zhao, Kangmin Niu, Yanbo Liu, Shih-Hsin Ho, Wei Wang, Yen Wei","doi":"10.1038/s41545-025-00474-2","DOIUrl":"https://doi.org/10.1038/s41545-025-00474-2","url":null,"abstract":"<p>Freshwater scarcity remains a critical global challenge, prompting the development of sustainable solutions like solar-driven interfacial water evaporation technology. Here, we present a scalable fabrication method for porous monolithic polymer evaporators through olefin metathesis polymerization coupled with NaCl templating. The large-area evaporator (800 × 600 mm²) incorporates amine-capped aniline trimer (ACAT) as a photothermal component within a dicyclopentadiene (DCPD)/cyclooctene (COE) polymer matrix, enabling efficient solar energy absorption and water transport. The optimized SDIE <b>PDCPD-25%COE-10%ACAT</b> exhibits notable performance in seawater desalination, wastewater treatment, and lithium salt enrichment. Under 1 sun irradiation, it achieves a pure water evaporation rate of 3.64 kg m⁻² h⁻¹ with a solar-thermal conversion efficiency of 96.7%, reflecting high energy utilization efficiency. Outdoor experiments under natural sunlight further confirm its operational feasibility, yielding an evaporation rate of 3.33 kg m⁻² h⁻¹. This work provides a viable route for the large-scale implementation of photothermal water treatment technologies, contributing to sustainable freshwater production and resource recovery.</p><figure></figure>","PeriodicalId":19375,"journal":{"name":"npj Clean Water","volume":"3 1","pages":""},"PeriodicalIF":11.4,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144146015","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}