The main purpose of this study is to introduce a modified method for recovering and recycling huge number of cigarette butts (CBs) and convert them into a fashion product. CBs are non-biodegradable waste, generally, discarded improperly into the environment. CBs consist of cellulose acetate, which can be recovered through extraction and purification processes. CBs are the most numerically frequent form of waste in the world. A relevant portion of CBS are discarded improperly into the environment. The principal filter components are plasticized cellulose acetate fibers that have the slowest degradation rate (up to years). In fact, a limiting step is the hydrolysis of cellulose acetate polymer into cellulose and acetic acid, which is extremely slow under ambient conditions and represents a relevant environmental risk. A number of studies have been realized on recycling cigarette butts with encouraging results, and several methods have been studied, including recycling of cigarette butts in asphalt concrete and fired clay bricks, as a carbon source, sound-absorbing material, corrosion inhibitor, biofilm carrier, and many more. In this study, we propose a novel, green, low cost, simple, and efficient extraction method of cellulose acetate fibers (CA) from discarded cigarette butts (DCBs). CBs extraction procedure involves a two-step process consisting of washings in water and some subsequent washings in ethanol. The obtained samples of CA are dried at 60 °C for 60 min in the oven. The quality and properties of cellulose acetate extracted and purified are comparable to the pure cellulose acetate fiber used for cigarette butts. The preliminary results obtained on the recovered CA look promising to the use of this recovery material from cigarette butts to obtain a wide consumption fashion product, such as eyeglass frames.

Hydrophobic surfaces are highly desired for several applications due to their exceptional properties such as self-cleaning, anti-icing, anti-friction and others. Such surfaces can be prepared via numerous methods including plasma technology, a dry technique with low environmental impact. In this paper, the effect of a one-step sulfur hexafluoride (SF₆) plasma treatment upon the low velocity impact behavior of basalt/epoxy composites has been investigated by using several characterization techniques. A capacitive coupled radiofrequency plasma system was used for the plasma surface treatment of basalt/epoxy composites, and suitable surface treatment conditions were experimentally investigated with respect to gas flow rate, chamber pressure, power intensity, and surface treatment time by measuring the water droplet contact angle of treated specimens. The contact angle measurements showed that treating with SF₆ plasma would increase the hydrophobicity of basalt/epoxy composites; moreover, the impact results obtained on reinforced epoxy basalt fiber showed damage in a confined area and higher impact resistance for plasma-treated basalt systems.

This work deals with optical fiber probes based on a photonic crystal deposited on the tip of a multi-mode optical fiber for relative humidity measurements. Easy manufacturing has been exploited through the self-assembly of core/shell nanoparticles in a colloidal crystal (CC) via a vertical deposition technique. Core/shell nanoparticles are synthetized having a polystyrene (PS) core and a hydrogel poly(N-isopropylacrylamide) (PNIPAM) shell. The swelling of the hydrogel shell due to water absorption makes the reflectance spectra of the photonic crystal dependent on the relative humidity in terms of wavelength shift and amplitude change of the reflected peak. Spectral characterization and sensing analysis of experimental probes are presented and discussed, showing that the absolute spectral characteristics of the proposed device are strongly manufacturing dependent. The sensing characteristic are highly nonlinear with Relative Humidity. A resolution of 1% RH is measuread at 30% RH that significantly decreases at higher RH. Moreover, a manufacture independent relative humidity sensor characteristic has been retrieved by a proper normalization of the response. Finally, a deeper insight into the sensor behaviour has been obtained by a theoretical model supported by TEM and DLS analysis. It suggests that the clustering of the PS/PNIPAM core/shell nanoparticles is mainly responsible for the fiber optic humidity response.

Thermal camouflage is a highly coveted technology aimed at enhancing the survivability of military equipment against infrared (IR) detectors. Recently, two-dimensional (2D) nanomaterials have shown low IR emissivity, widely tunable opto-electronic properties, and compatibility with stealth applications. Among these, graphene and graphene-like materials are the most appealing 2D materials for thermal camouflage applications. In multilayer graphene (MLG), charge density can be effectively tuned through sufficiently intense electric fields or through electrolytic gating. Therefore, MLG’s optical properties, like infrared emissivity and absorbance, can be controlled in a wide range by voltage bias. The large emissivity modulation achievable with this material makes it suitable in the design of thermal dynamic camouflage devices. Generally, the emissivity modulation in the multilayered graphene medium is governed by an intercalation process of non-volatile ionic liquids under a voltage bias. The electrically driven reduction of emissivity lowers the apparent temperature of a surface, aligning it with the background temperature to achieve thermal camouflage. This characteristic is shared by other graphene-based materials. In this review, we focus on recent advancements in the thermal camouflage properties of graphene in composite films and aerogel structures. We provide a summary of the current understanding of how thermal camouflage materials work, their present limitations, and future opportunities for development.

Casein-based composite materials show promise for sustainable applications due to their biodegradability and mechanical properties. With over 1.3 million tons of milk wasted annually, this study investigates repurposing this resource into composites reinforced with 50 wt% recycled cellulose and cellulose acetate fibers from cigarette butts. Mechanical testing revealed that composites with recycled cellulose fibers outperformed those with cellulose acetate, exhibiting a flexural modulus of 3527.7 MPa and a flexural strength of 24.2 MPa, compared to a flexural modulus of 1411 MPa and a flexural strength of 13.4 MPa for cellulose acetate. Shear strength tests also showed superior results for recycled cellulose (5.7 MPa) compared to cellulose acetate (3.3 MPa). Charpy impact tests further confirmed this trend, with impact strengths of 8.1 kJ/m² for cellulose and 6.7 kJ/m² for cellulose acetate. These findings highlight the potential of cellulose-reinforced casein composites as eco-friendly alternatives to synthetic materials, addressing both milk waste and cigarette pollution. By incorporating waste materials into the production process, this study aligns with the principles of the circular economy, promoting waste reduction, resource efficiency, and sustainability. Future research will focus on scalability, fiber treatments, and applications in construction, packaging, and automotive industries. Graphical abstract

Copper is widely used in both its metallic form and as oxide across numerous scientific and industrial domains. The primary copper oxides, cuprite (Cu₂O) and tenorite (CuO), naturally form on the copper surface and play a crucial role in advanced technologies, such as solar cells, lithium batteries, and sensors. Tenorite is appreciated for its optical properties, stability, low toxicity, and reactivity. While copper oxide thin films are traditionally synthesized through thermal treatments and oxidation in alkaline environments, these conventional high-temperature methods not only require significant energy consumption but can also compromise the metal–film interface. This study aims to develop a sustainable alternative approach for forming a homogeneous CuO layer on a copper substrate through environmentally friendly treatments based on low temperature, cost-effective, and time-saving procedures. Three different eco-conscious treatments were investigated: (i) immersion in NaOH basic solution, (ii) exposure to NaOH basic solution vapours, and (iii) a combined treatment involving both immersion and vapour exposure. This green synthesis approach significantly reduces energy consumption compared to traditional thermal methods while maintaining product quality. The surface oxide layer was investigated through an optical microscope (OM), scanning electron microscopy (SEM), spectrocolorimetric analysis, peel-off test, µ-Raman and X-ray photoelectron spectroscopy (XPS) analysis to investigate the surface oxidation state.