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To address modern tribological challenges—reducing friction and wear to conserve resources while minimising environmental impact—cobalt-doped DLC (Co-DLC) coatings were developed. These nanometric multilayer coatings, designed to retain key properties such as hardness, reduced modulus, and substrate adhesion, were fabricated using non-reactive DC magnetron sputtering (DCMS). The multilayer structure was achieved by controlling the planetary substrate holder's rotational speed. Characterisation of microscopic, chemical, structural, and mechanical properties was performed using techniques including FEI-SEM, EDS, XRD, TEM, Raman spectroscopy, scratch adhesion testing, and nanoindentation. Tribological performance was evaluated under boundary and fully flooded lubrication using PAO4 base oil and formulations with ashless, sulphur-free AW and EP additives. The coatings exhibited a granular surface morphology, columnar cross-sections, and amorphous structure. Increased dopant concentrations slightly enhanced graphitisation and significantly improved adhesion, though hardness and reduced modulus decreased. Tribological testing revealed superlubricity in several coating–oil combinations and significantly reduced wear rates with higher dopant levels and new additives. A phosphate ester additive without an amine group achieved the lowest COF values, while one with an amine group yielded minimal wear rates. These findings highlight the potential of Co-DLC coatings and tailored additives to minimise friction and wear effectively. [ABSTRACT FROM AUTHOR]

With low friction and high hardness, diamond-like carbon (DLC) coatings are a prominent surface engineering solution for tribosystems in various applications. Their versatility stems from their varying composition, facilitated by different deposition techniques, which affect their properties. However, environmental impact is often overlooked in coating design. The objective of this paper is to assess the resource efficiency of four different common deposition techniques, thus identifying critical factors for sustainable DLC deposition. The coatings were deposited in one single chamber, enabling a direct comparison of the resource consumption of each technology. Expenditure of electric energy and consumables per volumetric output accounted for the environmental impact of manufacturing the coatings, which was evaluated across the indicators of damage to human health, damage to ecosystems, and resource scarcity. Electric energy use, dictated by deposition rate, was demonstrated to be the most significant factor contributing to the environmental impact. The environmental impact of PECVD and μW-PECVD was comparable and remarkably lower than that of dcMS and HiPIMS, the latter being the least energy efficient process, with the lowest output rate but highest energy expenditure. Thus, μW-PECVD could be considered the 'greenest' production method. These findings are consequential for coaters to efficiently produce good-quality DLCs with low environmental impact. [ABSTRACT FROM AUTHOR]

Braking energy recovery (BER) aims to recover the vehicle's kinetic energy by coordinating the motor and mechanical braking torque to extend the driving range of the electric vehicle (EV). To achieve this goal, the motor/generator mode requires frequent switching and prolonged operation during driving. In this case, the motor temperature will unavoidably rise, potentially triggering motor thermal protection (MTP). Activating MTP increases the risk of motor component failure, and the EV typically disables the BER function. Thus, maximizing BER while reducing the risk of motor overheating is a challenging problem. To address this issue, this article proposes a predictive BER strategy with MTP using the non-smooth Pontryagin Minimum Principle (NSPMP) for EVs. Firstly, a Markov long short-term memory (MLSTM) model is designed to obtain future velocity information. Secondly, the BER problem with MTP in the studied EV is embedded in a model predictive control (MPC) framework. Then, under the MPC framework, the NSPMP strategy is proposed to resolve the problem of MTP. Finally, the performance of the proposed strategy is verified through simulation and a hardware-in-loop test. The results show that in two real-world driving cycles, compared to the rule-based strategy, the proposed strategy reduced power consumption by 1.24% and 0.96%, respectively, and effectively limited motor temperature. Additionally, under global cycle conditions, this strategy demonstrated better MTP control performance compared to other benchmark strategies. [ABSTRACT FROM AUTHOR]

The affinity interactions between boronic acids and sugars have been successfully exploited in many fields, such as the sensing of saccharides, selective enrichment of glycoconjugates, and drug delivery. However, despite multiple techniques having been adopted to investigate the reaction of boronate affinity, the pathway of boronate esters formation under aqueous conditions remains controversial. We report a MALDI-MS approach to investigate the interactions between phenylboronic acid and monosaccharides in neutral aqueous solution by using polylevodopa as an innovative substrate instead of conventional matrix. A series of unusual tri-benzeneboronic esters were then revealed. The mass spectrometry data indicate that they bear a dibenzenepyroboronate cyclic ester moiety with seven-membered ring or eight-membered ring. With the aid of theoretical computations, their most likely geometrical structures are elucidated, and these tri-benzeneboronic esters are proposed to be formed via a boroxine binding monosaccharide pathway. This work provides more insight into the mechanism of boronate affinity interaction between boronic acid and sugars and proves the developed MALDI-MS approach is promising for studying interactions between small molecules. [ABSTRACT FROM AUTHOR]

Hybrid electric air-ground vehicles (HEAGVs), which can run on the land and fly in the air, are considered a promising future transportation. The operation of HEAGVs, accompanied by high energy consumption, could lead to increasing battery temperature, which may affect the lifespan of the battery. To make the battery last longer and improve energy efficiency, an effective energy management strategy (EMS) is necessary for the operation of HEAGVs. In this regard, this paper proposes a predictive EMS based on model predictive control (MPC). Firstly, speed information is obtained by intelligent network technology to achieve a prediction of power demand, and then the state of charge (SOC) reference trajectory is planned. Secondly, a Pontryagin's minimum principle-based model predictive control (PMP-MPC) framework is proposed, including battery thermal dynamics. Under the framework, fuel efficiency is improved by reducing the temperature of the battery. Finally, the proposed method is compared to PMP, dynamic programming (DP), and rule-based (RB) methods. The effect of different preview horizon sizes on fuel economy and battery temperature is analyzed. Verification results under two driving cycles indicate that compared with the rule-based method, the proposed method improves fuel economy by 5.14% and 5.2% and decreases the temperature by 5.9% and 4.9%, respectively. The results demonstrate that the proposed PMP-MPC method can effectively improve fuel economy and reduce temperature. [ABSTRACT FROM AUTHOR]

Power flow optimization control, which governs the energy flow among engine, battery, and motor, plays a very important role in plug-in hybrid electric vehicles (PHEVs). Its performance directly affects the fuel economy of PHEVs. For the purpose of improving fuel economy, the electric system including battery and motor will be frequently scheduled, which would affect battery life. Therefore, a multi-objective optimization mechanism taking fuel economy and battery life into account is necessary, which is also a research focus in field of hybrid vehicles. Motivated by this issue, this paper proposes a multi-objective power flow optimization control strategy for a power split PHEV using game theory. Firstly, since the demand power of driver which is necessary for the power flow optimization control, cannot be known in advance, the demand power of driver can be modelled using a Markov chain to obtain predicted demand power. Secondly, based on the predicted demand power, the multi-objective optimization control problem is transformed into a game problem. A novel non-cooperative game model between engine and battery is established, and the benefit function with fuel economy and battery life as the optimization objective is proposed. Thirdly, under the premise of satisfying various constraints, the participants of the above game maximize their own benefit function to obtain the Nash equilibrium, which comprises of optimal power split scheme. Finally, the proposed strategy is verified compared with two baseline strategies, and results show that the proposed strategy can reduce equivalent fuel consumption by about 15% compared with baseline strategy 1, and achieve similar fuel economy while greatly extend battery life simultaneously compared with baseline strategy 2. [ABSTRACT FROM AUTHOR]

The establishment of an efficient and economic means of producing hydrogen via electrocatalytic water-splitting will facilitate the extensive commercialization of fuel cells, and the round-the-clock model of electrocatalytic hydrogen production will alleviate the intermittency issue associated with sustainable energy sources. To enable this feature of renewable hydrogen energy, the key point is to develop cheap, large-scale and high-performance hydrogen evolution electrocatalysts as an alternative to noble metals. Here, a simple and robust physically sputtering strategy is reported to massively prepare a porous and defect-enriched W2C@WC1−x film electrocatalyst on carbon cloth (CC) in a W, C and Ar ion plasma atmosphere. The preferential re-sputtering mechanism promotes the loss of activated W and C ions in plasma and extracts more C from plasma, resulting in the ultimate formation of a defective W2C@WC1−x film. The ratio of W2C to WC1−x increased and the particle size decreased when additional nano-scale thickness Mo sublayers were further incorporated. A monolithic and porous W2C@WC1−x/Mo multilayer film as a binder-free electrocatalyst on flexible CC is created. It exhibits excellent HER performance with a low overpotential of 58 mV vs. RHE to drive a current density of −10 mA cm−2, a low Tafel slope of 41 mV dec−1 and over 6 days of long-term running stability in 0.5 M H2SO4 solution. It outperforms most of the recently reported outstanding non-noble metal electrocatalysts. This work sheds light on a new route to regulate the tungsten-carbide catalyst morphology and composition with an aim to boost its HER activity. [ABSTRACT FROM AUTHOR]

Improvements in coating deposition technology enable the mass production of high-quality diamond-like carbon (DLC) coatings at an industrial scale and also increase their use in lubricated contacts. However, the understanding of the interactions of different lubricant additives with this material is not yet fully developed. This study focuses on several fundamental aspects of the tungsten-doped DLC coating (denoted as WDLC) behaviour under boundary lubrication conditions with model lubricants. The effect of lubricant additives on the coating structure change is discussed in terms of carbon structure and the tungsten dopant. Electron energy-loss spectroscopy, XPS and Raman spectroscopy characterization for the upper carbon layers indicate that the WDLC coating interacts chemically with selected lubricant additives. The study provides information on both coating and additive optimization under boundary lubrication. [ABSTRACT FROM AUTHOR]