Direct methanol fuel cells (DMFCs) represent a promising pathway for energy conversion, yet their reliance on platinum-group metal (PGM)-based anode catalysts poses critical sustainability challenges, which stem from finite mineral reserves, environmentally detrimental extraction processes, and prohibitive lifecycle costs. Current anode catalysts for DMFCs are dominated by platinum materials; therefore, this review systematically evaluates the following three emerging eco-efficient design paradigms using platinum materials as a starting point: (1) the atomic-level optimization of low-Pt alloy surfaces to maximize catalytic efficiency per metal atom, (2) Earth-abundant transition metal compounds (e.g., nitrides and sulfides) and coordination-tunable metal–organic frameworks as viable PGM-free alternatives, and (3) mechanically robust carbon architectures with engineered topological defects that enhance catalyst stability through covalent metal–carbon interactions. Through comparative analysis with pure Pt benchmarks, we critically examine how these strategic material innovations collectively mitigate CO intermediate poisoning risks and improve electrochemical durability. Such fundamental advances in catalyst design not only address immediate technical barriers, but also establish essential material foundations for the development of DMFC technologies compatible with circular economy frameworks and United Nations Sustainable Development Goal 7 targets.

The recycling of exhaust heat in internal combustion engines to dissociate the methanol, followed by its blending with methanol to produce engine fuel, is promising for improving the efficiency of engines, and reducing emissions. The kinetic model MEOHSYNGAS1.0 for the methanol–syngas fuel is proposed by reducing the detailed chemical kinetic model (Mech15.34). Shock tube experiments are conducted to measure the ignition delay time of methanol blended with dissociated methanol gas at different dissociated methanol ratios (0, 30, 50, and 100%). The model is validated by the experimental data of the present work and with data from the literature. The effects of the equivalence ratio, pressure, and dissociated methanol ratio on the ignition delay time are investigated through reaction path analysis and sensitivity analysis. When the dissociated methanol ratio does not surpass 50%, the ignition delay time increases with the increase in the dissociated methanol ratio, which is more obvious in the low temperature range, and but decreases with the increase in temperature.

In order to convert the marine diesel engine into an LNG (Liquefied Natural Gas)–diesel dual-fuel engine and ensure its power and emission characteristics, a new calibration method is proposed, and the fuel substitution ratio, economy and detailed particulate matter emission law after the engine is calibrated using this method are studied. The calibration method takes the peak pressure in the cylinder and the exhaust temperature as constraints and uses the diesel mass substitution ratio as the objective function. Based on the proposed calibration method, the engine is calibrated by setting up a calibration test bench. The test obtains the distribution characteristics of the diesel mass substitution ratio under various operating conditions of the engine. The results show that the proposed calibration method allows the dual-fuel engine to achieve the same power performance as the original engine. At the same time, the diesel mass substitution ratio of the calibrated dual-fuel engine can reach up to 95% (800 r/min @ 800 Nm, 900 r/min @ 800 Nm and 1000 r/min @ 800 Nm). The substitution ratio in the range of 900 r/min~1200 r/min at a common speed is more than 70%, and the average diesel mass substitution ratio under all working conditions is 71%. Furthermore, the study of engine economy shows that the BSFC (brake specific fuel consumption) of the dual-fuel mode is higher than that of the pure diesel mode when working under external characteristics, propulsion characteristics and different loads at 1000 r/min speed. This is more obvious when the load is small, and the two are closer when the load is medium or high; however, the fuel cost when the engine works in dual-fuel mode is much lower than that of the pure diesel mode. In the usual speed and load range, the particulate matter emission test shows that its particle size distribution, total number of particles and particle volume are significantly reduced in the dual-fuel mode.

The demand for clean and efficient new vehicle models is steadily increasing. Methanol-hydrogen engines use methanol as the main fuel and can recover the heat from engine exhaust to dissociate part of methanol into hydrogen-rich syngas. The syngas is recirculated back into the engine cylinder to improve combustion. Therefore, methanol-hydrogen engines have a higher energy utilization efficiency. This paper designed a methanol-hydrogen engine system based on a Miller cycle methanol engine. Bench tests showed that combusting methanol and dissociated methanol gas together could accelerate the fuel burn rate and improve the engine’s fuel economy. At a fixed engine speed of 2500 r/min, the BSFC of the methanol-hydrogen engine was reduced up to 5.55% compared to the original methanol engine. Further, a methanol-hydrogen extended-range electric vehicle powertrain model was built in Simulink. Simulation results indicated that, under the WTLC cycle, the methanol-hydrogen engine achieved a 22.60% reduction in fuel consumption per 100 km and saved 58.89% in fuel costs compared to the conventional gasoline engine. The methanol-hydrogen engine presented potential application in the extended-range electric vehicle.