pH-programmed MXene treatment alters PET textile interface and multifunctional performance

A laboratory study of PET textiles found that changing the aqueous treatment environment altered the surface chemistry, coating morphology and measured performance of fabrics functionalized with Ti3C2Tx MXene. The researchers compared neutral water, mildly acidic ascorbic-acid solution and strongly alkaline sodium hydroxide solution while keeping the nominal MXene concentration at 10% on fabric weight.

Plain-woven PET fabric with an areal density of 88 g/m² was treated at 100 °C for 60 minutes in an open beaker, then washed, dried and heat-fixed at 210 °C for 15 minutes. The three baths had approximate pH values of 6.5–7.0, 4.5–5.0 and 12.5. Commercially procured Ti3C2Tx with purity above 98% was used. This was a controlled materials experiment, not a clinical study or an assessment of finished consumer products.

Neutral treatment produced relatively large, multilayered MXene features, whereas ascorbic acid yielded the most exfoliated and conformal coating, with an observed sheet thickness of about 8 nm. Alkaline treatment produced smaller flakes but also caused visible pitting in the PET surface. These differences showed that the chemical environment changed more than the interface alone: coating size, stacking, oxidation and substrate morphology also varied among treatments.

Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy showed treatment-dependent changes in PET carboxylates and MXene surface states. The neutral sample retained the largest Ti–C fraction, while the acidic and alkaline samples showed increasing Ti–O and TiO2 contributions, with the alkaline sample showing the lowest Ti–C fraction. The combined findings were consistent with hydrogen bonding, coordination and possible localized Ti–O–C-type interactions, but the authors cautioned that these measurements did not establish a specific covalent bond or its strength.

X-ray diffraction indicated that processing also affected PET structure. Apparent crystallinity was 65.30% for untreated PET, 56.20% after neutral treatment, 39.24% after acidic treatment and 63.47% after alkaline treatment. The acidic condition therefore produced the greatest disruption of the X-ray-detectable ordered PET domains among the three treatments.

Under a 100 W infrared lamp for five minutes, MXene-coated fabrics reached mean surface temperatures of 82 ± 1.2 °C for neutral treatment, 76 ± 1.5 °C for acidic treatment and 81 ± 1.1 °C for alkaline treatment. Calculated photothermal conversion efficiencies were 86%, 77% and 84%, respectively. Thus, the more uniform acidic coating did not produce the highest peak temperature, showing that coating architecture and morphology were relevant to the measured response.

Under infrared irradiation, bacterial inhibition reached 99.2% for E. coli with the acidic-treated fabric and 98.8% for S. aureus with the alkaline-treated fabric. Complete ice melting took 21–22 minutes across the coated fabrics, compared with 30 minutes for untreated PET. Maximum X-band electromagnetic shielding was 21.73 dB for the acidic sample. After 24 hours of ultraviolet exposure, methylene-blue removal reached 98.4% for alkaline-treated fabric, 97.3% for acidic-treated fabric and 96.6% for neutral-treated fabric.

The treated fabrics retained tensile strengths of 301–321 N, equal to 111.5–118.9% of the untreated PET value, while abrasion mass loss remained between 0% and 1% after 20,000 Martindale cycles. However, alkaline exposure caused localized PET degradation, and several reported measurements were single observations. The study also did not establish long-term performance under repeated laundering, ultraviolet exposure, perspiration, deformation or environmental aging.

Overall, the experiments show that pH was an effective processing variable for tailoring Ti3C2Tx-coated PET textiles. The results support a combined effect of interfacial chemistry, MXene oxidation and termination chemistry, coating morphology and PET modification, rather than attributing performance differences to interfacial chemistry alone.

Subject of Research: Effect of pH-programmed hydrothermal treatment on Ti3C2Tx MXene-coated PET textiles

Article Title: pH-tunable interfacial chemistry of Ti 3 C 2 T x MXene on PET textiles for multifunctional performance

Article References: Shahin, S. M. T., & Montazer, M. (2026). pH-tunable interfacial chemistry of Ti3C2Tx MXene on PET textiles for multifunctional performance. Results in Engineering, 32, Article 113513. https://doi.org/10.1016/j.rineng.2026.113513

Image Credits: AI Generated

DOI: 10.1016/j.rineng.2026.113513

Keywords: Ti3C2Tx MXene, PET textile, interfacial chemistry, hydrothermal treatment, photothermal materials, antibacterial textiles, electromagnetic shielding, photocatalysis, deicing, surface functionalization, pH-tunable, interfacial