Facile synthesis of pinecone biomass-derived phosphorus-doping porous carbon electrodes for efficient electrochemical salt removal

Abstract

Electrochemical salt removal performance from water is greatly affected by the characteristics of porous carbon electrode materials. Nevertheless, facile eco-friendly synthesis of electrode materials with low cost for efficient salt electrosorption performance is still a huge challenge. Here, we readily prepared phosphorus-doped porous carbon derived from pinecones (PPCP), an abundant biomass waste, by using H3PO4 as the activating agent at appropriate activation temperature. The PPCP samples displayed an increase of the specific surface area and pore volume with rising activation temperature (700 − 900 °C). It has been demonstrated that the PPCP800 electrode displayed the highest specific capacitance due to relatively high specific surface area and degree of graphization, superior porous structure, the highest phosphorus content and lowest charge transfer resistance. Besides, the PPCP800 electrode displayed a high deionization capacity of 14.62 mg g−1 at 1.2 V in 1000 mg L−1 NaCl solution with the fastest salt removal rate. Furthermore, the prepared PPCP800 electrode exhibited good reproducibility in long-term consecutive operation. Hence, the phosphorus-doped porous carbons derived from pinecones might be promising candidates for capacitive deionization applications.