Highly Advanced Degradation of Thiamethoxam by Synergistic Chemisorption-Catalysis Strategy Using MIL(Fe)/Fe-SPC Composites with Ultrasonic Irradiation

Abstract

MIL(Fe)/Fe-doped nanospongy porous biocarbon (Fe-SPC) composite was fabricated from MIL-100(Fe) via in situ growth on a unique Fe-doped nanospongy porous biocarbon (Fe-SPC) and was used as Fenton-like catalyst for advanced degradation of thiamethoxam (THIA). Fe was loaded on silkworm excrement and calcined to Fe-SPC with nanospongy and high sp 2 C structure. The in situ growth strategy embedded the Fe-SPC into MIL-100(Fe) crystals and formed conductive heterojunctions with an intensified interface by Fe-bridging effect, which was confirmed by negative shift of Fe 3+ binding energy in X-ray photoelectron spectroscopy. MIL(Fe)/Fe-SPC composites exhibited high degree of crystallinity and surface area (Brunauer−Emmett−Teller: 1730 m 2 /g). Liquid chromatography−mass spectrometry and density functional theory simulations demonstrated that THIA was converted to a relatively stable compound (C 4 H 5 N 2 SCl), which could be captured by MIL-100(Fe) with strong chemical bonding energy (Fe−N, −587 kJ/mol), followed by a significant geometric distortion, resulting in a thorough degradation. Efficient charge separation and synergistic chemisorption-catalysis strategy resulted in the high catalytic activity of MIL(Fe)/Fe-SPC. The composite catalyst concurrently exhibited high mineralization ratio with 95.4% total organic carbon removal (at 25 °C and 180 min) and good recycling ability under wider neutral/alkaline conditions. Endorsing to these intriguing properties, MIL(Fe)/Fe-SPC can be deemed an efficient contender for removal of hard-degradable pesticides and other environmental pollutants in practical applications.

SERS‐Active MIL‐100(Fe) Sensory Array for Ultrasensitive and Multiplex Detection of VOCs

“…According to “hard and soft acid base” theory, isopropanol is classified as a hard base with strong affinity towards hard acids. Thus, Zr sites with higher hardness should preferably attract isopropanol [36] …”

“…Thus, Zr sites with higher hardness should preferably attract isopropanol. [36] Herein, according to the different adsorption ability of isopropanol on MOFs, zirconium (Zr) was selected to partially substitute Fe ions in MIL-100(Fe) to obtain the MIL-100(Fe-Zr) complex. Its XPS pattern showed that about 2 % of Zr was successfully replaced Fe on the MIL-100(Fe) surface ( Figure S9) via the ion exchange strategy.…”

Porous Fe@C Composites Derived from Silkworm Excrement for Effective Separation of Anisole Compounds

“…41,42 It is attributed to a special reconstruction of lamellar structures from mulberry leaf cellulose by silkworms through intestinal absorption. 43,44 After being calcinated with Fe species, SE was transformed into a 3D nano-spongy network packed with nanosheets (Figures S3B and 2B). This new Fe@C composite possesses many porous channels, providing a great diffusion pathway for molecules.…”

Low-Temperature Rapid Synthesis and Performance of the MIL-100(Fe) Monolithic Adsorbent for Dehumidification

“…Recently, metal–organic frameworks (MOFs), which are assembled with metal ions and multidentate organic linkers, have been intensively studied as a new class of porous materials. Due to their unprecedented specific surface area, adjustable chemical composition, and tunable porosity, MOFs have been considered as one of the most promising materials for various applications, such as gas storage and separation, − catalysis, − sensing, and dehumidification. , …”