Fuels For Propulsion Research Articles

Electroless Deposition of Ni Nanoparticles on Boron Particles: Physicochemical and Oxidation Properties

Elemental boron also has a high volumetric heat of combustion (136 kJ/cm3), the third highest gravimetric heat of combustion (58.5 MJ/kg) and its oxidation is a highly exothermic process. All these features make boron an attractive constituent of propellants, explosives, and high energy density solid fuels for air-breathing propulsion as an energetic material. Given these uses, researchers have worked on the ignition and combustion processes of boron. However, boron has several serious issues that limit its practical use, including large ignition delay, inefficient combustion, and a complex burning process in solid propellants due to the formation of a defensive boron oxide (B2O3) layer on the boron surface. Previous studies have found that the ignition and combustion performance of boron can be improved by coating it with metal particles, metal oxides, or organic materials, as well as by removing the boron oxide layer.In the literature, there are limited studies on metal particle coating of a boron surface using the electroless Ni plating method. The electroless coating has several impressive advantages over conventional electrolytic coating. The prime advantage is that electroless plating does not require any electricity to operate and is a low-cost process. Among other advantages, it provides a uniform coating and can be used with all kinds of substrates with complex shapes. Conductive and non-conductive materials/powders can be coated with constant thickness with good adhesion.The present work investigated Ni nanoparticle coating on irregularly shaped/non-spherical boron particles using the electroless Ni-plating method at room temperature to prevent the oxidation of boron particles. This is preferable since it is very difficult to coat large quantities at relatively high temperatures. The four different simple paths were chosen during the electroless Ni plating to coat Ni on boron particles: no rinsing and no drying (Path A), only drying (Path B), both rinsing and drying (Path C) and only rinsing (Path D). Previous studies have explored the effect of bath concentration, pH, and temperature on the Ni coating. However, the influence of the four different paths mentioned above on Ni coating with boron particles or any other materials has rarely been investigated. Surface morphology confirmed the Ni nanoparticles coating on the surface of boron particles. The size of the Ni nanoparticles varied between 10 and 120 nm concerning the chosen paths used for preparation using TEM. XRD characterization results of the Ni coated boron particles showed the formation of crystalline Ni nanoparticles. EDAX and XPS results showed the presence of the primary B and Ni elements in samples synthesized in the present study. Thermogravimetric analysis conducted in air atmosphere found the boron particles coated with Ni nanoparticles had enhanced oxidation resistance compared to bare boron particles. Also, the Ni coated boron particles showed a shift in exothermic peak to a lower temperature and higher heat evolution than the bare boron particles.Acknowledgements:This work was supported by the National Research Foundation (NRF) of Korea grant funded by the Korea government (MSIT) No. 2019R1A2C1010862, 2022R1A2C2013508

Investigation of Charging Technologies for Electric Vehicles

In today's world, internal combustion engine vehicles are widely used. These vehicles cause harmful emissions as they use fossil fuels for engine propulsion and vehicle movement. To address this issue, electric vehicles have been considered as a solution. In electric vehicles, electric motors are used instead of traditional internal combustion engines and the necessary electrical energy is supplied from battery packs. In this way, electric vehicles do not cause harmful emissions to the environment. If the energy required for electric vehicle charging stations is obtained from renewable energy systems, electric vehicles will be zero-emission vehicles. Battery packs, that provide energy for electric vehicles, typically consist of rechargeable Lithium-ion battery groups and they can be charged using fast charging technology. In this study, the future of transportation, electric vehicles and the standards and technologies used in electric vehicle charging stations have been examined. Additionally, an electric vehicle system has been designed using MATLAB/Simscape.

Comparative analysis among different alternative fuels for ship propulsion in a well-to-wake perspective

The shipping sector is required to give a significant contribution to the reduction of Green House Gas (GHG) emissions, according to the ambitious goals fixed by the International Maritime Organization (IMO). To achieve these targets, new technologies and measures are required, related to logistics, digitalization, hydrodynamics, machinery, energy, and aftertreatment. A large potential to reduce GHG emissions is offered by alternative fuels. In this perspective a Well-to-Wake (WtW) approach is due for a comprehensive analysis. The paper is focused on the evaluation of WtW CO2 equivalent emission factors for LNG, methanol, and ammonia. The extensive bibliographic research on this topic outlines the large differences occurring when considering grey or green fuel production pathways. A case study based on a cruise ship allows to compare alternative fuels produced from fossil or renewable sources, considering two typical cruise profiles. Results in terms of Carbon Intensity Indicator confirms that the WtW approach points out the great potential of alternative green fuels for GHG emissions reduction.

Perspectives on shipping emissions and their impacts on the surface ocean and lower atmosphere: An environmental-social-economic dimension

Shipping is the cornerstone of international trade and thus a critical economic sector. However, ships predominantly use fossil fuels for propulsion and electricity generation, which emit greenhouse gases such as carbon dioxide and methane, and air pollutants such as particulate matter, sulfur oxides, nitrogen oxides, and volatile organic compounds. The availability of Automatic Information System (AIS) data has helped to improve the emission inventories of air pollutants from ship stacks. Recent laboratory, shipborne, satellite and modeling studies provided convincing evidence that ship-emitted air pollutants have significant impacts on atmospheric chemistry, clouds, and ocean biogeochemistry. The need to improve air quality to protect human health and to mitigate climate change has driven a series of regulations at international, national, and local levels, leading to rapid energy and technology transitions. This resulted in major changes in air emissions from shipping with implications on their environmental impacts, but observational studies remain limited. Growth in shipping in polar areas is expected to have distinct impacts on these pristine and sensitive environments. The transition to more sustainable shipping is also expected to cause further changes in fuels and technologies, and thus in air emissions. However, major uncertainties remain on how future shipping emissions may affect atmospheric composition, clouds, climate, and ocean biogeochemistry, under the rapidly changing policy (e.g., targeting decarbonization), socioeconomic, and climate contexts.

Reduction of CO2 Emissions from Offshore Combined Cycle Diesel Engine-Steam Turbine Power Plant Powered by Alternative Fuels

Abstract Diverse forms of environmental pollution arise with the introduction of materials or energy that exert adverse effects on human health, climate patterns, ecosystems, and beyond. Rigorous emission regulations for gases resulting from fuel combustion are being enforced by the European Union and the International Maritime Organization (IMO), directed at maritime sectors to mitigate emissions of SOx, NOx, and CO2. The IMO envisions the realisation of its 2050 targets through a suite of strategies encompassing deliberate reductions in vessel speed, enhanced ship operations, improved propulsion systems, and a transition towards low and zero-emission fuels such as LNG, methanol, hydrogen, and ammonia. While the majority of vessels currently depend on heavy fuel or low-sulphur fuel oil, novel designs integrating alternative fuels are gaining prominence. Technologies like exhaust gas purification systems, LNG, and methanol are being embraced to achieve minimised emissions. This study introduces the concept of a high-power combined ship system, composed of a primary main engine, a diesel engine, and a steam turbine system, harnessing the energy contained within the flue gases of the main combustion engine. Assumptions, constraints for calculations, and a thermodynamic evaluation of the combined cycle are outlined. Additionally, the study scrutinises the utilisation of alternative fuels for ship propulsion and their potential to curtail exhaust emissions, with a specific focus on reducing CO2 output.

Synthesis of Renewable High-Density Fuel with Vanillin and Cyclopentanone Derived from Hemicellulose

1,3-bis(cyclohexylmethyl)cyclopentane, a renewable high-density fuel, was first produced in a high overall carbon yield (79.5%) with vanillin and cyclopentanone, which can be derived from biomass. The synthetic route used in this work contains two steps. In the first step, 2,5-bis(4-hydroxy-3-methoxybenzylidene)cyclopentanone was synthesized by aldol condensation of vanillin and cyclopentanone under the catalysis of sulphuric acid. Over the optimized condensation, a high carbon yield (82.6%) of 2,5-bis(4-hydroxy-3-methoxybenzylidene) cyclopentanone was achieved at 80 ºC. In the second step, 2,5-bis(4-hydroxy-3-methoxybenzylidene) cyclopentanone was hydrodeoxygenated over the Pd/HY catalyst in cyclohexane as solvent. High carbon yields of 1,3-bis(cyclohexylmethyl)cyclopentane (96.2%) was obtained. The polycycloalkane mixture as obtained has a density of 0.943 g mL−1 and a freezing point of −35 °C. It can be blended into conventional high-density fuels (e.g., JP-10) for rockets and missile propulsion as a potential application.

Reliability-Based Analysis of Main Propulsion Fuel Oil System Maintenance for Tugboats with Qualitative and Quantitative Methods

This study aims to analyze the maintenance of the main propulsion fuel oil system for tugboats using both qualitative and quantitative methods. The focus is on evaluating the reliability of the system and identifying potential areas for improvement. The research employs a combination of expert interviews, industry standards, and statistical analysis to provide a comprehensive overview of the maintenance practices in place. The goal is to enhance the overall performance and longevity of the main propulsion fuel oil system in tugboats. The study uses data on the operational time, failure time and frequency, the number of vessels served, and fuel system diagrams to analyze the system's reliability. Qualitative methods such as Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA) were used, as well as quantitative methods such as Overall Equipment Effectiveness (OEE), Markovian Decision Process (MDP), and reliability methods. The study found that the FO Purifier component was the critical component with a Risk Priority Number (RPN) of 294. The average value of OEE was 47%, lower than the standard of 85%. The MDP analysis showed a probability of 0.08 for mild damage and 0.46 for moderate to severe damage under steady-state conditions. The FO Purifier component had the lowest Mean Time to Failure (MTTF) value of 1658.50 hours. The study provides a graph of the reliability function against time, and recommends maintenance actions based on the MTTF and MDP.

Addressing the range anxiety of battery electric vehicles with charging en route

Battery electric vehicles (BEVs) have emerged as a promising alternative to traditional internal combustion engine (ICE) vehicles due to benefits in improved fuel economy, lower operating cost, and reduced emission. BEVs use electric motors rather than fossil fuels for propulsion and typically store electric energy in lithium-ion cells. With rising concerns over fossil fuel depletion and the impact of ICE vehicles on the climate, electric mobility is widely considered as the future of sustainable transportation. BEVs promise to drastically reduce greenhouse gas emissions as a result of the transportation sector. However, mass adoption of BEVs faces major barriers due to consumer worries over several important battery-related issues, such as limited range, long charging time, lack of charging stations, and high initial cost. Existing solutions to overcome these barriers, such as building more charging stations, increasing battery capacity, and stationary vehicle-to-vehicle (V2V) charging, often suffer from prohibitive investment costs, incompatibility to existing BEVs, or long travel delays. In this paper, we propose Peer-to-Peer Car Charging (P2C2), a scalable approach for charging BEVs that alleviates the need for elaborate charging infrastructure. The central idea is to enable BEVs to share charge among each other while in motion through coordination with a cloud-based control system. To re-vitalize a BEV fleet, which is continuously in motion, we introduce Mobile Charging Stations (MoCS), which are high-battery-capacity vehicles used to replenish the overall charge in a vehicle network. Unlike existing V2V charging solutions, the charge sharing in P2C2 takes place while the BEVs are in-motion, which aims at minimizing travel time loss. To reduce BEV-to-BEV contact time without increasing manufacturing costs, we propose to use multiple batteries of varying sizes and charge transfer rates. The faster but smaller batteries are used for charge transfer between vehicles, while the slower but larger ones are used for prolonged charge storage. We have designed the overall P2C2 framework and formalized the decision-making process of the cloud-based control system. We have evaluated the effectiveness of P2C2 using a well-characterized simulation platform and observed dramatic improvement in BEV mobility. Additionally, through statistical analysis, we show that a significant reduction in carbon emission is also possible if MoCS can be powered by renewable energy sources.

Thermal, Viscosimetric and Thermomechanical Combined Assessment of Mixture Modelled Composite Fuels for Hybrid Propulsion

AbstractParaffin‐based fuels have received attention in hybrid propulsion studies towards their regression rate assessment, although little efforts have been dedicated to a consistent selection of their formulations. This work deals with melting enthalpy, dynamic viscosity, and linear thermal expansion characterization of novel low‐density polyethylene‐macrocrystalline paraffin‐ammonium nitrate composite fuels, followed by model fitting under mixture modeling principles and subsequent optimization through the desirability method. This approach allowed a better understanding of the raw materials’ roles and provided a trade‐off formulation, which was satisfactorily produced and characterized in a confirmatory experiment, thus making it a suitable candidate for further regression rate measurements.

Comprehensive Performance Evaluation of Densified Liquid Hydrogen/Liquid Oxygen as Propulsion Fuel

Densified liquid hydrogen/liquid oxygen is a promising propulsion fuel in the future. In order to systematically demonstrate the benefits and challenges of densified liquid hydrogen/liquid oxygen, a transient thermodynamical model considering the heat leakage, temperature rise, engine thrust, pressurization pressure of the tank, and wall thickness of tank is developed in the present paper, and the performance of densified liquid hydrogen/liquid oxygen as propulsion fuel is further evaluated in actual application. For liquid hydrogen/liquid oxygen tanks at different structural dimensions, the effects of many factors such as temperature rise during propellant ground parking, lift of engine thrust, mass reduction of the tank structure, and extension of spacecraft in-orbit time are analyzed to demonstrate the comprehensive performance of liquid hydrogen/liquid oxygen after densification. Meanwhile, the problem of subcooling combination matching of liquid hydrogen/liquid oxygen is proposed for the first time. Combining the fuel consumption and engine thrust lifting, the subcooling combination matching of liquid hydrogen/liquid oxygen at different mixing ratios and constant mixing ratios are discussed, respectively. The results show that the relative engine thrust enhances by 6.96% compared with the normal boiling point state in the condition of slush hydrogen with 50% solid content and enough liquid oxygen. The in-orbit time of spacecraft can extend about 2–6.5 days and 24–95 days for slush hydrogen with 50% solid content and liquid oxygen in the triple point state in different cryogenic tanks, respectively. Due to temperature rise during parking, the existing adiabatic storage scheme and filling scheme for densification LH2 need to be redesigned, and for densification LO2 are suitable. It is found that there is an optimal subcooling matching relation after densification of liquid hydrogen/liquid oxygen as propulsion fuel. In other words, the subcooling temperature of liquid hydrogen/liquid oxygen is not the lower the better, but the matching relationship between LH2 subcooling degree and LO2 subcooling degree needs to be considered at the same time. It is necessary that the LO2 was cooled to 69.2 K and 54.5 K, when the LH2 of 13.9 K and SH2 with 45% was adopted, respectively. This research provides theoretical support for the promotion and application of densification cryogenic propellants.

Review on design, preparation and performance characterization of gelled fuels for advanced propulsion

Review on design, preparation and performance characterization of gelled fuels for advanced propulsion

Design and preparation of liquid polycyclic norbornanes as potential high performance fuels for aerospace propulsion

High-energy-density (HED) liquid fuels are required for modern and perspective volume-limited aircrafts to extend the flight distance and to increase the speed. In this work, we report on the synthesis of a new set of HED liquid polycyclic norbornane-containing hydrocarbons and on the study of their key physico-chemical characteristics. A facile route to the desired hydrocarbons was developed through modifications of a cheap commercial diene, 5-vinyl-2-norbornene, using [2 + 2]- and [4 + 2]-cycloaddition reactions. Physico-chemical properties of the obtained hydrocarbons, such as density, freezing point, viscosity and heat of combustion, were systematically studied. Some of the hydrocarbons exhibited an enhanced combination of the properties: high heats of combustions, densities up to 1.0799 g/mL, freezing points in the range of +15 °C to below −60 °C and kinematic viscosities up to 1.89 mm2·s−1. The successive modifications of 5-vinyl-2-norbornene significantly improved the energy density (≤45.38 MJ/L) of the produced hydrocarbons over the widely used related fuel, JP-10. Thus, the developed norbornane-containing hydrocarbons can be considered as new promising HED liquid fuels for advanced propulsion.

Qualitative Analysis of Spray Characteristics of Impinging Jets Using A Gelled Non-Newtonian Propellant Simulant

The utilization of liquid and solid fuels for propulsion and combustion processes with Newtonian characteristics are widely known. However, recent studies are considering the application of shear-thinning non-Newtonian fuels as alternative simulant since they have some advantages compared to the conventional propellants although there are challenges of providing better spray performance during the corresponding process. This paper, therefore, presents the results of the experimental investigations of the “near-field” spray characteristics with utilizing imaging techniques which evaluates the sheet formation and breakup length of four different spray patterns produced by the jet impingement of a gelled non-Newtonian propellant simulant. The qualitative analysis of this study shows that the spray patterns are different compared to those that are shaped by using Newtonian liquid fuels. This could lead to supposition that the non-Newtonian rheology of the gelled propellant simulant postponed the sheet and ligaments breakup, including the mode change of the atomization. In addition, the atomization of the sheet at different flow parameters could occur due to the formation and the sheet wave instability when aerodynamic and hydrodynamic of their origin are closely considered. This was further supported by the occurrence of perforations in the sheet.

Hybrid propulsion and alternative fuels education in the course of decarbonised shipping

ABSTRACT The study investigates marine engineering education on alternative fuels and hybrid propulsion regarding decarbonisation of shipping. A new course is proposed for maritime education and training subject to the IGF Code amendments to the STCW which lasts 14 weeks and 3 h per week. Competences at the STCW amendments for the persons who work on alternative-fuelled ships are taken into account while preparing the course topics. Each topic is paired with basic and advanced training competencies of the STCW amendments, compliance with the STCW is provided, the course topics and sub-topics are explained, and the duration of the course is determined. The need for updating the curriculum and the training of future seafarers is crucial to satisfying their ability to operate future ships. This study highlights the need for novel approaches and courses regarding the new future technologies for the traditional marine engineering curriculum.

Synergistic effect of a hybrid additive for hydrogen peroxide-based low toxicity hypergolic propellants

Hypergolic bipropellants based on high-test peroxide (HTP, >85% H2O2) have traditionally emerged as low-toxicity propellants for space applications. However, the late-ignition performance of HTP-based fuel restricts its potential use in particular applications, such as high-precision auxiliary response thrusters. In this study, the synergistic effects of new hybrid additives (reactive additive: catalytic additive), NaBH4:NaI, and NaBH4:NH4I were, for the first time, demonstrated to improve the ignition performance of low-toxicity fuels with 95 wt.% H2O2. The effect of changes in the weight percentage ratios of the reactive and catalytic additives on the ignition performance was investigated. The fuels without additives were non-hypergolic with 95 wt.% H2O2. However, at specific concentrations, the hybrid additives in fuels markedly lowered the ignition delay time (IDT) to less than 3 ms. Notably, ethylenediamine containing 10 wt.% hybrid additives of NaBH4:NaI and NaBH4:NH4I at a specific additive weight ratio (6.5:3.5) yielded an average IDT of 2.75 and 2.69 ms, respectively. Thermal analysis revealed that the hybrid additive improved the thermal stability of the fuels. The theoretical vacuum-specific impulse of these fuels was calculated using the NASA-CEA code. The results of this study confirm the validity of our approach for developing relatively low-toxicity hypergolic fuels for space propulsion.

Laboratory scale method for preparation of mixture modeled composite fuels for hybrid propulsion

ABSTRACT Fuel formulation is one of the chief strategies investigated in hybrid propulsion studies. In this context, polyethylenes-paraffins compositions have been suggested as a trade-off solution to attain both mechanical quality and ballistic performance. In parallel, mixed hybrids have already proven their capacity to enhance regression rates of thermoset polymers in mixture-modelled experiments. Ammonium perchlorate replacement by ammonium nitrate could turn mixed hybrids into environmentally benign materials. Meanwhile, the preparation of hybrid fuels based on paraffins and thermoplastic polymers seems to lack an application-oriented approach, capable to generate macroscopically homogeneous and symmetrical samples, compatible with both instrumental and ballistic measurements. Therefore, this work successfully outlines a laboratory scale preparation method developed to generate cylindrical composite fuel grains for hybrid propulsion, comprising low-density polyethylene (LDPE), macrocrystalline paraffin and ammonium nitrate mixture-modelled formulations, as well as applies thermogravimetry and differential scanning calorimetry to gain insight into their microstructural aspects, particularly their miscibility and its relation to the observed macroscopic behavior.

Operating Parameters and Environmental Indicators of Diesel Engines Fed with Crop-Based Fuels

Abstract A comparative analysis of performance of Diesel engines fuelled by diesel oil, methyl ester of rapeseed oil and raw rapeseed oil was performed. The analysis of external characteristics of engines powered by various fuel types was accepted for an assessment. Engine performance rates were analysed while attention was paid to power courses, moment, unit fuel consumption and hour fuel consumption, exhaust fumes temperature and exhaust smoke. Operation effectiveness of engines was assessed when they were fed with various fuel types and optimal proportions of fuel mixtures were indicated. Environmental aspects of powering the engines with traditional fuels and crop-based fuels were analysed. The total CO2 emission in the entire process of manufacturing and combustion of fuels was accepted as a criterion. A simplified economic analysis was performed in the aspect of the underlying purpose of using crop-based fuels for propulsion of piston engines. Conclusions and recommendations that indicate directions of development concerning the analysed issue were prepared.

High-resolution thermal analysis of nuclear thermal propulsion fuel element using OpenFOAM

This paper conducts high-resolution thermal hydraulic analysis of a Nuclear Thermal Propulsion (NTP) Fuel Element (FE) using a finite volume approach. Recent NTP design efforts have focused on using low-enriched uranium (LEU) fuel as an alternative to the historical highly-enriched uranium (HEU) fuel. In addition to changing materials’ properties, variations in dimensions and flow characteristics are also considered. This makes the applicability of legacy experimental data questionable for the new LEU designs, as the data was generated for a specific range of design characteristics. Nowadays, there is limited accessibility to experimental capability under realistic hot hydrogen conditions. However, some experimental setups could be replaced or complemented by higher-order numerical analysis, which is the end objective of the computational framework developed here. This study implements a 3D conjugate heat transfer (CHT) numerical solver between solid and fluid regions using OpenFOAM Computational Fluid Dynamic (CFD) toolbox. The hydrogen flow in the fluid region is simulated using Reynolds-averaged Naiver-Stokes (RANS) model, while the solid region is modeled using a conduction heat transfer solver. The 3D simulation results are validated against experimental data obtained from the Nuclear Engine for Rocket Vehicle Application (NERVA) Nuclear Rocket Experimental (NRX) A6 program. The latter shares similar design parameters with modern NTP systems, such as dimensions and flow conditions. In addition, legacy heat transfer correlations were implanted in a reduced-order 1.5D semi-analytic solution, and the results were compared against the OpenFOAM solution. The results presented in this paper conclude that OpenFOAM can serve as a high-resolution thermal hydraulic code both for reproducing legacy experiments and educating reduced-order models.

Ultrafast igniting, low toxicity hypergolic hybrid solid fuels and hydrogen peroxide oxidizer

The hydrazine derivatives, conventional hypergolic fuels, are highly toxic and carcinogenic; inspiring the search for safe and environmentally friendly hypergolic fuels. Hypergolic solid fuels (HSFs) containing amine-boranes, paraffin wax, and metal additives (MnO2-C, Pt-Ru-C, and Pd-C) were evaluated as new safe hypergolic fuels for space propulsion. Further, the hypergolic combustion of HSFs wasdemonstratedwith an environmentally friendly storable oxidizer, (95% H2O2). The effect of change in the weight percentage of ammonia borane (AB) and Pd-C on hypergolic ignitions were studied. A very small quantity of additive ‘triggers’ the hypergolic combustion of HSFs. HSFs containing 1 wt% of Pt-Ru-C and Pd-C additives exhibited ultrafast ignition delay times (IDTs) of 2.0 and 1.2 ms, respectively. Other than AB fuel, the dimethyl-imidazolium-borane, and tetramethyl-diamino-bisborane also demonstrated their application for HSFs. The thermal and chemical stability of HSF were evaluated by using DSC-TGA and powder XRD, respectively. The XRD study of HSF containing AB, Pd-C, and paraffin wax confirmed theβ-PdHxphase, which was maintained for 9 weeks under air atmosphere and proves the stability of HSF. Hence, such low toxicity propellants of HSFs and H2O2oxidizer can be promising choices for green space propulsion.

Micromotor That Carries Its Own Fuel Internally.

Micromotors enjoy burgeoning interest but a limitation of their design is to require continuous supply of new fuel. The preponderance of extant micromotors depend, for their motion, on irradiation by light or exposure to acid in their environment. Here we demonstrate a motor that carries its own fuel internally, in this sense representing an analogue, in micron-sized objects, of the internal combustion engine. The fuel is DPCP (diphenylcyclopropenone) microcrystal, a solid-state chemical that after ignition by UV light requires no further irradiation to sustain a chemical reaction that emits carbon monoxide gas that can be used to propel the particle on which this chemical resides. It is loaded asymmetrically onto inexpensive microparticles to produce internally fueled propulsion with speed up to ∼20 μm/s over distances up to 15 times the capsule length in water. Once ignited, the motors maintain their direction of motion and move without need for light to follow their path. Possible strategies to extend the idea beyond the current proof of concept are discussed.