Heteroatoms-doped Transition Metal Dichalcogenides Confined in Mesoporous Nitrogen-doped Carbon Microspheres With Radial Pores for NO2 Sensing

Transition metal dichalcogenides (TMDs) have attracted significant attention in electronic devices, energy storage, and catalysis owing to their distinctive electronic properties and abundant active sites. Introducing mesoporosity into TMDs is extremely favorable to enhance the host-guest interactions and improve their performance, but very challenging. Herein, we report a universal electrostatic assembly strategy for the synthesis of mesoporous carbon/heteroatom-doped TMDs microspheres with radially oriented pores, using polydopamine (PDA) and polyoxometalates (POMs) clusters as interactive precursors. By employing POMs (e.g., H 3 PW 12 O 40 ) as metal sources and mesoporous PDA microspheres as templates, we successfully synthesized a series of mesoporous C/heteroatom-doped TMDs microspheres (TMDs = P-WS 2 , Si-WS 2 , P-MoS 2 , Si-MoS 2 ). The resulting hybrid microspheres feature an open porous architecture, high charge-carrier mobility, and abundant active sites, benefiting from their high crystallinity and in situ heteroatom doping. When employed in chemiresistive gas sensors, these C/TMDs microspheres demonstrate exceptional room-temperature NO 2 sensing performance, including high sensitivity, excellent selectivity, and rapid response. Density functional theory (DFT) calculations reveal that heteroatom doping (e.g., P) can enhance the structural stability of adsorbed NO 2 , strengthen orbital hybridization with TMDs, and facilitate efficient charge transfer, thereby dramatically improving sensing performances.