Xuan Zhao , Dan Li , Linghui Deng , Ying Chen , Shujie Hu , Mengyue Zhang , Di Wu , Hong Liu , Yuan Liu
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引用次数: 0
Abstract
Prussian blue analogues hold great promise for directly extracting potassium resource from wastewater via hybrid capacitive deionization (HCDI). However, there remain unresolved scientific issues regarding low efficiency and selectivity arising from asymmetric potential distribution induced by spontaneous charge matching. This work systematically investigated the underlying mechanisms for enhancing the storage capacity and specific affinity of representative Berlin Green towards K+ through precise regulation of insertion potential during HCDI operation. Empowered by controlling electrochemical intercalation behaviors, the compatibility between ionic and electronic kinetics was significantly enhanced. Impressive values of 160.12 mg/g, 61.27 %, and 0.07 kWh/mol were achieved under potentiostatic mode (0.1 V vs. Ag/AgCl) for insertion capacity, charge efficiency, and energy consumption, respectively. These results significantly outperformed the optimal levels obtained under constant cell voltage (0.9 V), which were 128.52 mg/g, 47.50 %, and 0.12 kWh/mol, respectively. In both aqueous solution with binary components and urine, the results emphasized the potential of the synergy effect between lattice hindrance and insertion chemistry in promoting intercalation selectivity, with the highest selectivity coefficients of 28.35 (K+/Na+), 76.22 (K+/Ca2+) and 175.12 (K+/Mg2+), respectively. The presented concept-to-proof offers a versatile approach for the advancement of high-performance HCDI and paves the way towards its sustainable application in nutrient recycling from natural waters or wastewaters.
期刊介绍:
Water Research, along with its open access companion journal Water Research X, serves as a platform for publishing original research papers covering various aspects of the science and technology related to the anthropogenic water cycle, water quality, and its management worldwide. The audience targeted by the journal comprises biologists, chemical engineers, chemists, civil engineers, environmental engineers, limnologists, and microbiologists. The scope of the journal include:
•Treatment processes for water and wastewaters (municipal, agricultural, industrial, and on-site treatment), including resource recovery and residuals management;
•Urban hydrology including sewer systems, stormwater management, and green infrastructure;
•Drinking water treatment and distribution;
•Potable and non-potable water reuse;
•Sanitation, public health, and risk assessment;
•Anaerobic digestion, solid and hazardous waste management, including source characterization and the effects and control of leachates and gaseous emissions;
•Contaminants (chemical, microbial, anthropogenic particles such as nanoparticles or microplastics) and related water quality sensing, monitoring, fate, and assessment;
•Anthropogenic impacts on inland, tidal, coastal and urban waters, focusing on surface and ground waters, and point and non-point sources of pollution;
•Environmental restoration, linked to surface water, groundwater and groundwater remediation;
•Analysis of the interfaces between sediments and water, and between water and atmosphere, focusing specifically on anthropogenic impacts;
•Mathematical modelling, systems analysis, machine learning, and beneficial use of big data related to the anthropogenic water cycle;
•Socio-economic, policy, and regulations studies.