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Thermal management of buildings consumes 51% of the world's energy use. Optimization of the energy use can be potentially achieved via daylight harvesting and radiative cooling approaches, yet their simultaneous utilization under static conditions is challenging due to opposite operation principles. Here, an in situ switchable photoselective polymer (PSP) material was prepared by sequential electrospinning of light-reflecting and light-absorbing layers made of contrasting polymer nanofibers. The as-prepared PSP material exhibited a high solar light reflectance of 97.7% and a high broadband emissivity of 94.9% resulting in a radiative cooling power of 111.1 W m−2. Such "cooling" state of the PSP film can be easily switched to a "heating" one via impregnation of an index matching liquid that suppresses scattering at the film–air interface and reduces the solar band reflectivity of the film. Thanks to the highly porous structure of the designed PSP film, its switching takes less than 5 min and allows an integrated solar absorbance of ∼95.6% to be achieved, resulting in an estimated heating power of 781.6 W m−2. Performed numerical calculations further supported the high potential of the developed PSP film for thermal management of buildings located at high latitudes with energy savings up to 89.74 GJ m−2 per year and reduced CO2 emissions down to 21.69 t. [ABSTRACT FROM AUTHOR]

Tannin-immobilized cellulose was prepared by the phenolic reaction of the phenol ring of tannin with the aldehyde group of aldocellulose, where aldocellulose was prepared by the oxidization of cellulose with sodium periodate as oxidizing agent. The method of immobilized tannin is environmentally friendly due to the lack of crosslinking agent. The adsorption properties of cellulose were improved due to the introduction of tannin. The maximum adsorption capacity of the tannin-immobilized cellulose for berberine hydrochloride was 143.66 mg/g. The isothermal adsorption for berberine hydrochloride conformed to the Langmuir model well. The adsorption of tannin-immobilized cellulose for berberine hydrochloride was a weak chemical adsorption, and the adsorption process was exothermic. The adsorption equilibrium was reached within 90 min in the initial concentration 100 mg/L, and the sorption kinetics fitted well to a pseudo-first-order model. Tannin-immobilized cellulose has potential application prospect in the field of the separation and purification of alkaloids. [ABSTRACT FROM AUTHOR]

Lithium ion sieve adsorbents frequently extract liquid lithium resources due to their adsorption effect and cost advantages. However, the adsorption effect is significantly influenced by the ambient pH. The pH effects on the adsorption process can be categorized into two main areas: the competition adsorption of impurity ions and the difference in surface zeta potential. A dual-matrix modulation adsorbent was prepared, comprising a carrier matrix modified with zwitterionic quaternary ammonium bases and an adsorption matrix modified with carboxylation. The zwitterionic quaternary ammonium base groups were employed to mitigate the competitive adsorption of impurity ions by acid-base neutralization. Furthermore, the negative charge of carboxyl groups was employed to diminish the discrepancy in surface zeta potential. The adsorption effect of the ion sieve adsorbent under natural conditions appeared to be significantly enhanced by the dual-matrix modulation, with the saturated adsorption capacity (28 mg/g) and adsorption selectivity (α(Li + /Mg 2+ )=24.23) being 6.3 and 7.8 times higher than that of the manganese-based adsorbent (HMO) under the same conditions, respectively. Moreover, the adsorption effect was found to be consistent with HMO under alkaline conditions. The results demonstrate that by optimizing the adsorption conditions of the adsorbent, the detrimental impact of pH on the adsorption process of lithium ion sieves can be eliminated., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)