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The presented studies concern the effects of graphite flake (GF) on the properties of a specific and challenging type of composite, that is, phenolic-carbon fabric (PC) composites. This type of materials are commonly used in large scale, but the studies in this manuscript try to explain in detail the effects of graphite on the characteristics of composites. The results show that Young's modulus exhibits increasing trend however tensile strength and interlaminar shear strength show decrement on increasing the GF content in the PC-GF composites. Dynamic mechanical thermal analysis (DMTA) reveals that storage modulus (E') increases by ~42% and 139% upon addition of 10 and 40 wt% GF in the PC-GF composites, respectively. Loss modulus (E') of the composites shows a drastic improvement (~145%) upon addition of only 10 wt% GF. Moreover, various interfacial interaction parameters such as entanglement density (N), reinforcement efficiency factor (r), C factor (the effectiveness of fillers on the modulus of the composites), interphase adhesion factor (A), and 'b' factor (fiber volume correction factor) of the composites are also evaluated using the data obtained from DMTA and correlated with mechanical properties of the composites., INTRODUCTIONCarbon fiber reinforced composite materials are widely used because of their excellent physical, thermal and mechanical properties [1, 2]. Among polymers, phenolic resins are finding their increased applications due to [...]

A rapid microwave (180 s, 100 W) green approach has been demonstrated for the synthesis of TiO2 tripods (TITPs) using Mangifera indica leaf extracts. In this process, mangiferin acts as an efficient reducing agent while microwave radiations control the nucleation and growth of anisotropic TiO2 nanostructure. Surface morphological analyses reveal that synthesized TiO2 nanomaterial has a unique resilient shape of tripods with porosity. The photocatalytic ability of synthesized TITPs has been examined using Methylene blue (MB) as the target contaminant, and ∼75% (under visible light in 75 min) and 96% (under UV in 9 min) dye degradation has been achieved. The TITPs show recyclability for up to three cycles. Moreover, TITPs exhibit good adsorbent property that varies with the change of temperature and pH. The adsorption of the MB by TITPs follows the pseudo-first-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity of TITPs is found to be 17.54 mg/g based on the Langmuir model. The present multi-facet TITPs prepared via a simple and quick (180 s) microwave method has the potential for application in photocatalytic/adsorption for aqueous contaminant remediation. [ABSTRACT FROM AUTHOR]

A conjugated mesoporous polymer with a donor–acceptor approach (TBPA-phen) is synthesized via tetrakis(triphenylphosphine)palladium-catalyzed Sonogashira coupling and is exploited for in situ modification with cobalt (Co@TBPA-phen). The polymers exhibit a charge-separated state and semiconducting behavior at room temperature. The microscopy images reveal spherical morphology and multipoint Brunauer–Emmett–Teller analysis confirms the presence of mesoporosity (d = 2.6–4.5 nm). TBPA-phen exhibits significant electrochemical activity for the oxygen reduction reaction (ORR) with a low onset potential of 0.80 V vs. the reversible hydrogen electrode (RHE) and hydrogen evolution reaction (HER) with an overpotential of −486 mV @10 mA cm−2. But merely 6.3 wt% Co stabilized Co@TBPA-phen drives the oxygen evolution reaction (OER) at an overpotential of 480 mV @10 mA cm−2 along with the ORR (Eonset = 0.82 V vs. RHE) and HER (−335 mV @10 mA cm−2) at reduced overpotentials. Our density functional theory computations disclose the descriptor for every reaction along with validating that facilely synthesized polymers are exquisite donor–acceptor pairs. The natural bond orbital study provides orbital interactions and charge transfer in the ORR and OER and supports cobalt stabilized in Co@TBPA-phen in Co(0) and Co(II) states. A rechargeable Zn–air battery bestows an open circuit voltage of 1.51 V, a specific capacity of 723 mA h g−1, and a significant discharge potential of 1.2 V with no change in the voltage window of 0.75 V for up to 108 cycles. The study unravels strategically designed conjugated mesoporous polymers as efficient trifunctional electrocatalysts for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]