A dual center polyoxometalate non-aqueous liquid phase platform engineered by Jahn-Teller & sulfonic acid for H2S valorization to S/H2.

Conventional aqueous-phase technologies in wet desulfurization processes have long been plagued by equipment corrosion and solvent volatilization, while non-aqueous systems suffer from the bottleneck of insufficient active sites, severely hindering the development of efficient and sustainable desulfurization technologies. To address this, we developed a novel transition-metal-substituted polyoxometalate sulfonic-acid functionalized deep eutectic solvent (TPMDES) desulfurization system, enabling deep modulation of the electronic structure of active sites and the interfacial microenvironment in non-aqueous desulfurization systems. Characterization results and density functional theory calculations reveal that the Jahn-Teller distortion induced by precise Cu2 + substitution in tri-copper-substituted phosphomolybdic acid (PMo9Cu3) combined with short-chain sulfonic acid (MIMPs) functional groups, jointly constructs an "electron-deficient-Cu/electron-rich-Mo" polyoxometalate (POM) dual reaction center within the basic microenvironment provided by natural amino acid-based deep eutectic solvents. This unique design establishes two charge transfer pathways (Cu2+→O2-→Mo6+ and MIMPs→O2-→Mo6+), which enhances the electron-modulating capability of the POM, thereby improving the hydrogen sulfide (H2S) capture performance of TPMDES. The optimal desulfurizer TPMDES achieves complete H2S removal for over 120 min continuously at 75 °C. The introduction of electrochemical technology enables the system to maintain over 80% desulfurization activity after multiple regeneration cycles, effectively overcoming the critical challenge of balancing high reactivity with long-term stability in non-aqueous desulfurization systems. Furthermore, the electrochemical regeneration process simultaneously achieves sulfur enrichment and the co-production of clean energy hydrogen, driving a technological shift from mere waste gas treatment to resource recovery. This work provides a practical solution for developing non-aqueous desulfurization systems that integrate high activity, outstanding medium stability and resource recovery potential.