Location:
Professor Guandao Gao, the environmental functional materials and water pollution control team, has been committed to the interdisciplinary and applied basic research of unconventional electricity (piezoelectric, thermoelectric and triboelectric) in the field of water treatment, actively exploring the penetration and application of electrical physical effects in environmental protection. Focusing on the common challenges and demands of the membrane pollution prevention and control, green regeneration of adsorbent and proper disposal of concentrated solution faced by mainstream separation technologies in the process of efficient and low-carbon wastewater treatment and recycling, the membrane separation, adsorption and catalytic materials with electric response were accurately designed and prepared. By further combining the electricity-related physical effects and relying on the external physical field to reversibly adjust the state of charge on the surface of functional materials, innovative materials, methods and coupling technologies for solvent-free cleaning membrane pollution, green regeneration adsorbent, and electrical control of catalytic process have been established. "Reactance pollution" (Nature, 2022, 608, 69 – 73; Environment. Sci. Technol. 2022, 56, 10997 – 11005; J. Membr. Sci. 2021, 638, 119722;), "Electrodesorption" (Environment. Sci. Technol. 2018, 52, 12602 – 12611; Environment. Sci. Technol. 2018, 52, 739 – 746), "Electric catalysis" (Environment. Sci. Technol. 2015, 49, 2375 – 2383; Chemosphere. 2022, 303, 135119) were proposed as the core of the new concept of low carbon water treatment technology by electric control, which expands the traditional application fields of electrochemistry, electrophysics and other disciplines, and enriches the scientific basis and practice of field control and surface interface performance enhancement.
"Electric catalysis" includes electrically controlled catalyst energy level, in situ regeneration, electric field activation of pollutants, and electrically controlled adsorption-desorption equilibrium (sabatier effect). Recently, the research group reported an impressive in situ dipole-sourced electrostatic field modulation strategy for crystal facet engineering of model catalyst. Such a dipole-sourced and electrically tunable strategy substantially shortens synthetic steps and avoids the surfactants or capping agents that may alter the catalytic reactivity. This methodology brings more possibilities for engineering crystal structures for sustainable chemistry. This research was published in PNAS on February 21, 2023 with the title of "Electrostatic-induced green and precise growth of model catalysts". The first author of the paper is Qiancheng Xia, a doctoral student, and the corresponding authors are Professor Guandao Gao and Dr. Chao Wang of Yangzhou University. The collaborators include Bin Liu, and Yongguang Bu, Professor Zhenda Lu and Yuchen Zhang of college of engineering and applied sciences, and associate professor Shuang Li and Tao Shen of Nanjing University of Science and Technology.
Crystallographic control of crystals as catalysts with precise geometrical and chemical features, is significantly important to develop sustainable chemistry, yet highly challenging. Encouraged by first principles calculations, precise structure control of ionic crystals could be realized by introducing an interfacial electrostatic field. Herein, we report an efficient in situ dipole-sourced electrostatic field modulation strategy using polarized ferroelectret, for crystal facet engineering towards challenging catalysis reactions, which avoids undesired faradic reactions or insufficient field strength by conventional external electric field. Resultantly, a distinct structure evolution from tetrahedron to polyhedron with different dominated facets of Ag3PO4 model catalyst was obtained by tuning the polarization level, similar oriented growth was also realized by ZnO system. Theoretical calculations and simulation reveal that the generated electrostatic field can effectively guide the migration and anchoring of Ag+ precursors and free Ag3PO4 nuclei, achieving oriented crystal growth by thermodynamic and kinetic balance. The faceted Ag3PO4 catalyst exhibits high performance in photocatalytic water oxidation and nitrogen fixation for valuable chemicals production, validating the effectiveness and potential of this crystal regulation strategy. Such an electrically tunable growth concept by electrostatic field, provides new synthetic insights and great opportunity to effectively tailor the crystal structures for facet-dependent catalysis.
This work was supported by National Natural Science Foundation of China (Grant No. 21976085), the Fundamental Research Funds for the Central Universities (Grant No. 14380154), and the Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX22_0168).
Figure. Electrostatic-induced green and precise growth of model catalysts for challenging catalysis reactions.
