Fenghai Li

Formaldehyde (HCHO) poses a serious threat to human health due to its irritability and carcinogenicity. However, developing HCHO capture materials with ultra‐high HCHO capacity under humid conditions remains an enormous challenge. Herein, a novel strategy for polymerization‐based anchorage of HCHO is first reported. The ionic liquids (ILs, Carbamide sulfate ([CAM][SO ₄ ])) can exhibit a visual perceptual capture effect, representing a new type of adsorption interaction. [SO ₄ ] ²⁻ of [CAM][SO ₄ ] nanodots dissolve the generated H ₂ O while ensuring the anchorage of HCHO in [CAM] ²⁺ , thereby promoting the reaction and increasing the HCHO capacity. Specifically, [CAM][SO ₄ ]@MIL‐101(Cr)‐20%, based on [CAM][SO ₄ ] and metal‐organic frameworks (MOFs, MIL‐101(Cr)), has exhibited recorded HCHO capture (19.38 mmol/g), which is 4.73 times as high as that of the parent MIL‐101(Cr). Not only that, the breakthrough experiment proves that the superior separation factor (SF) of HCHO/H ₂ O can reach 10.0 while the HCHO concentration can be reduced by 5 orders of magnitude (from 800 ppm to less than 1 ppb within 1210 min/g). Furthermore, mechanism analysis elucidates that the superior performance is attributed to the synergistic effect of the tripartite functional structure in [CAM][SO ₄ ]@MIL‐101(Cr). Our findings provide new molecular‐level insights into HCHO capture, expanding our understanding of the principles for the rational design of future adsorbents.

Biomass energy plays a critical role in alleviating environmental pressures. However, its relatively high content of alkali metals (especially for potassium) would cause ash‐related issues during combustion. To mitigate these issues, the potassium migration behaviors during chestnut shell (CS) conversion and the modification mechanisms of solid waste additives (fish bone and fly ash) under oxidizing atmosphere were investigated. When the mass ratio of fish bone ash or fly ash increased from 0% to 40%, the potassium retention both increased (fish bone: 5%–33%; fly ash: 5%–43%), and fly ash showed a better potassium‐fixation performance under the same conditions. The phosphorus and calcium from fish bone reacted with potassium to form high‐melting‐point (MP) K‐Ca phosphates (KCa ₂ P ₃ O ₁₀ ), which increased potassium retention rate obviously. The replacement of some potassium in silicates by the calcium from fish bone might mitigate potassium retention of CS ashes. With the addition of fly ash, its elevated silicon and aluminum concentrations effectively inhibit potassium leaching through the precipitation of high‐MP potassium aluminosilicate phases (KAlSi ₃ O ₈ ). The combination of XRD and FactSage analyses provides a mechanistic interpretation of potassium migration behavior under oxidizing atmospheres.

The global freshwater scarcity crisis demands sustainable solutions aligned with circular economy principles. Solar-driven steam generation (SSG) has emerged as a promising approach to obtain freshwater from seawater or wastewater using solar energy. However, its widespread application relies on the development of energy-efficient, eco-friendly, and high-performance photothermal conversion materials. Herein, we present a sustainable strategy for converting autumn-fallen plane tree leaves into a photothermal material (AC-800) via KOH activation at 800 °C. AC-800 exhibits 91% broadband absorption (250–2500 nm). A light-absorbing layer fabricated by vacuum filtration was used for SSG tests. Under 1 sun irradiation, AC-800 achieves an evaporation rate of 1.5441 kg·m⁻²·h⁻¹ with 87.1% solar-to-vapor efficiency and a surface temperature of 48.3 °C. Ten repetitive cycles of experiments using AC-800 has demonstrated the cycling stability of SSG. Desalinated water meets World Health Organization (WHO) drinking water standards, and organic dye removal from wastewater in distilled water reaches ~100%. This low-cost, eco-friendly strategy advances sustainable SSG, with potential in seawater desalination and wastewater treatment to support circular economy objectives.

The effects of coal gangue (CG) on the ash initial deformation temperature (IDT) and CO₂ gasification characteristic of biomass (chestnut shell [CS] and soybean straw [SS]) were investigated by ash fusion tester and thermogravimetric analyzer, respectively. The IDTs of CS and SS ashes were low because of the presence of abundant low melting point (MP) airchildite (K₂Ca(CO₃)₂) and arcanite (K₂SO₄), and they were efficiently improved by the CG additions of 2%–10% mass ratios. The increases in the IDTs of CS and SS ashes were resulted from the conversions of fairchildite and arcanite into high MP K‐Al silicates (kalsilite [KAlSiO₄], leucite [KAlSi₂O₆], etc.). The gasification reactivities of CS/CG mixtures stayed below that of CS, and they decreased with increasing CG mass ratios (4%–10%) and increased with increasing temperatures (900–1000°C). At 900°C, CG addition caused a decrease in the gasification reactivity of SS. When the temperature reached 950°C, the CG addition of 4% mass ratio increased the gasification reactivity of SS instead. The synergistic effect between biomass and CG during cogasification was more significant at low CG mass ratio and high temperature, and the synergistic effect between SS and CG was more intense than that between CS and CG.

Co-combustion of solid waste and biomass can alleviate biomass ash-related problems. To investigate the effects of solid waste on the ash fusion characteristics of biomass and its variation mechanisms under an oxidation atmosphere, an X-ray diffraction, thermogravimetric analyzer (TG), scanning electron microscope (SEM), and FactSage calculation were used to examine the ash fusion behaviors of sorghum straw (SS) with the addition of textile dyeing sludge (TDS) or chicken manure (CM). The ash fusion temperature (AFT) of SS increased gradually with the TDS ash addition; with CM ash addition, the AFT of SS mixtures increased rapidly (0–20%), decreased slightly (20–30%), and finally increased slowly (30–60%). The generations of high melting point (MP) minerals (e.g., KAlSi₂O₆, Fe₂O₃, and Fe₃O₄) led to an increase in the AFT of TDS-SS mixtures. The K⁺ in silicate was gradually replaced by Mg²⁺ or Ca²⁺, which caused the generations of high-MP minerals (e.g., Ca₃MgSi₂O₈, Ca₂MgSi₂O₇, and CaMgSiO₄). The TG analysis showed that the additions of TDS or CM ash slowed down the weight loss of SS mixed ash due to the formation of high-MP minerals. The SEM and FactSage calculations were also explained with the AFT change and their variation mechanisms. The result provided effective references for the AFT regulation during the co-combustion of biomass and solid waste.