Pengfei Wang

Gold is indispensable to modern technologies, yet its supply remains heavily dependent on environmentally intensive primary mining. Rapidly accumulating electronic waste (e‐waste) represents a valuable urban mine, but Au recovery is still constrained by corrosive lixiviants, co‐dissolution of competing metals, and high reagent demand. Herein, defect‐anchored Pt–Ov–Ti charge bridges are proposed to couple photogenerated‐carrier dynamics with iodine redox cycling, achieving 98.25% Au dissolution within 2 h while limiting the co‐dissolution of competing metals to below 0.62%. Multiple lines of evidence indicate that Pt–Ov–Ti sites promote interfacial charge transfer and carrier utilization, enabling hole‐driven I ⁻ oxidation and O ₂ ‐assisted iodine redox cycling. In situ characterization and theoretical calculations further reveal that Pt–Ov–Ti induces local interfacial redistribution, introduces Pt 5d‐derived frontier states, and enhances iodine species adsorption and charge transfer, enabling reversible interfacial electronic‐state evolution during iodide activation. This pathway enabled the dissolution of 196.04 mg of Au from 1 kg of discarded central processing units (CPUs) with Au accounting for 99.2% of the leached metals, while retaining >95% activity after 10 cycles and supporting catalyst recycling and iodine reuse. This work highlights defect‐associated interfacial charge‐transfer engineering as a promising strategy for directing photogenerated carriers toward selective ligand‐mediated leaching and sustainable precious‐metal recovery.

Gold is indispensable to modern technologies, yet its supply remains heavily dependent on environmentally intensive primary mining. Rapidly accumulating electronic waste (e‐waste) represents a valuable urban mine, but Au recovery is still constrained by corrosive lixiviants, co‐dissolution of competing metals, and high reagent demand. Herein, defect‐anchored Pt–Ov–Ti charge bridges are proposed to couple photogenerated‐carrier dynamics with iodine redox cycling, achieving 98.25% Au dissolution within 2 h while limiting the co‐dissolution of competing metals to below 0.62%. Multiple lines of evidence indicate that Pt–Ov–Ti sites promote interfacial charge transfer and carrier utilization, enabling hole‐driven I ⁻ oxidation and O ₂ ‐assisted iodine redox cycling. In situ characterization and theoretical calculations further reveal that Pt–Ov–Ti induces local interfacial redistribution, introduces Pt 5d‐derived frontier states, and enhances iodine species adsorption and charge transfer, enabling reversible interfacial electronic‐state evolution during iodide activation. This pathway enabled the dissolution of 196.04 mg of Au from 1 kg of discarded central processing units (CPUs) with Au accounting for 99.2% of the leached metals, while retaining >95% activity after 10 cycles and supporting catalyst recycling and iodine reuse. This work highlights defect‐associated interfacial charge‐transfer engineering as a promising strategy for directing photogenerated carriers toward selective ligand‐mediated leaching and sustainable precious‐metal recovery.

Selective solar oxidation of ethylene glycol (EG) derived from waste poly(ethylene terephthalate) (PET) to glycolaldehyde (GAld) is hindered by the high reactivity of the aldehyde intermediate, which readily undergoes overoxidation and C─C cleavage. Here, we report an exfoliated polymeric carbon nitride (PCN) photocatalyst with atomically dispersed Pd sites (Pd _SA /PCN) that arrests EG photooxidation at the C ₂ aldehyde stage. In PET hydrolysate, optimized Pd _SA /PCN achieves a GAld formation rate of 2479 µmol g _cat ⁻¹ h ⁻¹ with 92.8% selectivity; in gram‐scale upgrading of real PET waste, the selectivity reaches 95.9%. Mechanistic studies suggest that Pd single atoms function as electron‐extraction centers, removing electrons from long‐lived, low‐energy localized states in PCN and increasing surface‐accessible holes for selective alcohol dehydrogenation. Meanwhile, Pd sites strengthen EG adsorption and lower the barrier for initial O─H activation, favouring alkoxy intermediates while limiting ·OH‐type overoxidation and C─C scission. The catalyst converts diverse real polyester wastes under fluctuating natural sunlight while maintaining >90% GAld selectivity. Coupled techno‐economic and geospatial analyses identify priority deployment regions with a median annual net profit of US$5.95 million, highlighting the potential of single‐atom materials for solar plastic upcycling to C ₂ platform molecules.

Mineralization‐driven advanced oxidation processes (AOPs) effectively remove emerging pollutants but often require substantial energy input and generate considerable carbon emissions, conflicting with carbon‐neutrality goals. Here, we develop a transformation‐focused AOP based on cobalt‐doped lanthanum oxycarbonate (Co‐LC), which activates peroxymonosulfate (PMS) to selectively generate singlet oxygen ( ¹ O ₂ ). Experimental and theoretical results reveal that Co–La bonding interactions reconfigure the local electronic environment, stabilize high‐valent O* intermediates, and lower the energy barrier for ¹ O ₂ formation. The Co‐LC/PMS system exhibits a transformation rate 49.23 times that of pristine LC and selectively destroys the carcinogenic amino and naphthalene moieties of 1‐naphthylamine. Ecotoxicological assays using Chlorella vulgaris confirm complete elimination of biological risks, with physiological indicators returning to baseline levels after treatment. A continuous‐flow packed‐bed reactor maintained >94% removal efficiency for 37 days and increased the BOD ₅ /COD ratio of real wastewater from 0.25 to 0.50. Life‐cycle assessment further shows 85.6% lower CO ₂ emissions and reduced operating costs compared with the Co ₃ O ₄ /PMS system. This study establishes a low‐carbon detoxification strategy that prioritizes toxicity elimination over complete mineralization for sustainable water purification.

For diverse wastewater treatment scenarios, achieving controllable switching of reactive oxygen species within a unified catalytic system remains a major challenge. Here, an inert cation substitution strategy is proposed to regulate tetrahedral and octahedral Co activity in Co ₃ O ₄ , enabling controllable switching between radical and nonradical pathways. Octahedral‐Co‐enriched ZnCo ₂ O ₄ (ZCO) selectively directs peroxymonosulfate (PMS) activation toward the ¹ O ₂ pathway (95.8% contribution), whereas tetrahedral‐Co‐dominated CoAl ₂ O ₄ (CAO) favors radical oxidation, with •OH (76.4%) and SO ₄ ^•− (21.7%) dominating. This polyhedral‐dependent pathway control leads to distinct oxidation behaviors. Notably, the ZCO/PMS system achieved nearly 100% o‐nitrophenol (ONP) degradation within 4 min, with a k ‐value of 71.81 min ⁻¹ M ⁻¹ , 32.2 times that of Co ₃ O ₄ . Multiple lines of evidence reveal that polyhedral‐site engineering governs PMS adsorption geometry, interfacial charge redistribution, and O─O bond activation, thereby determining pathway selection. These differentiated functions were further translated into bench‐scale municipal wastewater treatment, with ZCO/PMS increasing the effluent Biochemical oxygen demand/chemical oxygen demand (BOD/COD) ratio from below 0.3 to consistently above 0.5 over 80 h and CAO/PMS decreasing the effluent TOC from ∼25 mg L ⁻¹ to below 12 mg L ⁻¹ over 60 h. Both systems exhibited low biotoxicity and favorable sustainability, offering a practical route toward selective energy‐efficient advanced oxidation.

Sustained and selective generation of singlet oxygen ( ¹ O ₂ ) in Fenton‐like catalytic systems is highly desirable for diverse applications, from freshwater resource management to green chemical synthesis. Despite advances in advanced oxidation processes, there remains a lack of generalizable methods that reliably modulate ¹ O ₂ selectivity. Here, we propose a descriptor‐assisted coordination modulation strategy, in which machine‐learning analysis identifies the d‐band center as an important electronic descriptor associated with ¹ O ₂ selectivity. Through N‐coordination modulation, the CoN ₅ catalyst exhibited near‐complete ¹ O ₂ selectivity among the quantified reactive oxygen species (ROS) with a steady‐state concentration of 394 µM, outperforming recent reports. As an internal‐circulation pre‐oxidation module, the CoN ₅ /peroxymonosulfate (CoN ₅ /PMS) system continuously raised wastewater biochemical oxygen demand/chemical oxygen demand (BOD/COD) to above 0.5 over 192 h, increased bioavailable dissolved organic matter (DOM), and showed high microbiome compatibility, evidenced by reduced Vibrio fischeri inhibition and microbial diversity ordination clustering near the background with greater shared‐taxa overlap. This system also enabled selective thioanisole oxidation, achieving 90.6% conversion and 99.5% selectivity, with green synthesis potential demonstrated in a three‐chamber continuous single‐pass reactor. These results establish a generalizable coordination principle for steering ROS pathways and provide a deployable, low‐ecological‐risk route for both mixed wastewater treatment and green chemical synthesis.

Sustained and selective generation of singlet oxygen ( ¹ O ₂ ) in Fenton‐like catalytic systems is highly desirable for diverse applications, from freshwater resource management to green chemical synthesis. Despite advances in advanced oxidation processes, there remains a lack of generalizable methods that reliably modulate ¹ O ₂ selectivity. Here, we propose a descriptor‐assisted coordination modulation strategy, in which machine‐learning analysis identifies the d‐band center as an important electronic descriptor associated with ¹ O ₂ selectivity. Through N‐coordination modulation, the CoN ₅ catalyst exhibited near‐complete ¹ O ₂ selectivity among the quantified reactive oxygen species (ROS) with a steady‐state concentration of 394 µM, outperforming recent reports. As an internal‐circulation pre‐oxidation module, the CoN ₅ /peroxymonosulfate (CoN ₅ /PMS) system continuously raised wastewater biochemical oxygen demand/chemical oxygen demand (BOD/COD) to above 0.5 over 192 h, increased bioavailable dissolved organic matter (DOM), and showed high microbiome compatibility, evidenced by reduced Vibrio fischeri inhibition and microbial diversity ordination clustering near the background with greater shared‐taxa overlap. This system also enabled selective thioanisole oxidation, achieving 90.6% conversion and 99.5% selectivity, with green synthesis potential demonstrated in a three‐chamber continuous single‐pass reactor. These results establish a generalizable coordination principle for steering ROS pathways and provide a deployable, low‐ecological‐risk route for both mixed wastewater treatment and green chemical synthesis.

H ₂ O ₂ ‐based advanced oxidation processes are promising for water purification, but free‐radical‐dominated pathways are often inhibited by coexisting inorganic anions in high‐salinity environments. Here, we develop a Cu single‑atom doped graphitic carbon nitride nanosheet catalyst and reveal that abundant Cl ⁻ in seawater is converted from a potential radical scavenger into an active participant in H ₂ O ₂ activation. The Cu ₁ ‑N ₃ /H ₂ O ₂ /Vis system achieves rapid degradation of 1‑naphthylamine (1‑NA) in seawater, with an apparent rate constant 69 times higher than that of the CN/H ₂ O ₂ /Vis system. Mechanistic results suggest that Cu ₁ ‐N ₃ sites promote H ₂ O ₂ activation and facilitate Cl ⁻ ‐involved pathway reconfiguration, leading to the formation of reactive chlorine species (RCS)‐related intermediates, ¹ O ₂ , and high‐valent Cu‐associated oxidative species. These species collectively establish a cooperative radical/non‐radical oxidation network, rather than a conventional free‐•OH‐dominated pathway. Continuous‐flow tests further demonstrate stable 1‐NA removal during 20 h operation. This work provides a promising strategy for Cl ⁻ ‐steered photo‐Fenton pathway reconfiguration toward high‐performance seawater decontamination.

Per‐ and polyfluoroalkyl substances (PFAS) are called forever chemicals due to the extremely stable C─F bond (bond energy of 485 kJ·mol ⁻¹ ), which leads the persistent existence in the natural environment thus poses a threat to human health. Compared with simple removal without destruction, defluorination is a more meaningful and thorough way for the harmless disposal of PFAS. In this review, the relationship between the structural properties of PFAS and defluorination mechanism are concluded. Thereafter, we discussed the advantages and limitations of defluorination techniques and specific defluorination pathways of active substances (free radicals and electron). This will provide a comprehensive theoretical foundation for the selection and improvement of defluorination technologies. The influence of key factors on the practical application of defluorination technologies in wastewater treatment plants are assessed in detail from the perspectives of reaction solvents, homogeneous and heterogeneous systems, and reactor design. Importantly, the pilot‐scale application of relevant PFAS defluorination technologies has also been discussed. Finally, we prospect for the future research direction of PFAS defluorination from the aspects of precise exploration of reaction pathways, fluorine balance, resource recovery, and life cycle assessment (LCA). This will provide a practical strategy for addressing the urgent issue of PFAS‐contaminated wastewater.