【Frontiers in HaiChuan Chemical Technology】Electrocatalysis: Prospects and Key Roles in Shaping the Future of Electrochemistry

02 Emerging Directions in Electrocatalysis The emerging directions in electrocatalysis focus mainly on the following key areas: 1. CO₂ reduction reaction (CO₂RR), which aims to convert carbon dioxide into valuable chemicals; this is of great significance for the carbon cycle and reducing greenhouse gas emissions； 2. Nitrogen fixation (N₂ reduction), namely the conversion of nitrogen gas into nitrogen-containing compounds such as ammonia through electrocatalysis, provides a new approach for the production of green fertilizers and similar applications ； 3. The electrocatalytic conversion of biomass-derived chemicals enables the transformation of components in biomass into bulk chemicals, helping to reduce dependence on fossil resources ； 4. Electrocatalytic production of hydrogen peroxide (H₂O₂): As a clean oxidizing agent, hydrogen peroxide has important applications in various industrial fields, and this approach holds significant industrial potential. The development of electrocatalysis faces various challenges: 1. Scientific and technical challenges, including the scalability of reactions – such as how to increase electrode size and optimize operational conditions – as well as the fact that the performance of certain reactions (such as CO₂RR and NRR) has not yet met the requirements for industrial application ； 2. Cost issues: The fixed and operational costs associated with electrocatalytic technology remain too high; it is necessary to reduce these costs by improving the design of electrocatalysts/electrodes and optimizing operating conditions ； 3. Research limitations: Current studies focus primarily on the mechanism and design of electrocatalysts, with insufficient attention paid to systems engineering. There is also a lack of in-depth exploration into the synergistic use of different reactions. Additionally, in terms of theoretical methods, no unified electrochemical and electrocatalytic theory has yet been developed to guide the design of new electrocatalysts.

03 From electrocatalysis to photocatalysis: The shift from electrocatalysis to photocatalysis represents an important pathway for transforming energy and chemical production toward a sustainable, circular, and resilient future. The key lies in integrating the ability to utilize sunlight directly by developing photocatalytic (PEC) devices. There are mainly two types of PEC devices: one type has photoactive units integrated into the anode section (PECa), where the photoactive functions are typically incorporated into the anode; although it is possible to make both the anode and the cathode photoactive, practical implementation faces many difficulties ； Another approach is to have the photoactive units exist externally as photovoltaic units (PV/EC) and be integrated into the cell eventually, with their configuration based on independent photovoltaic cells driving the electrocatalytic units. In the PECa compact battery design, the cathode and anode are located directly on either side of the membrane, which reduces transmission limitations and improves performance; moreover, gas diffusion electrodes can be used to eliminate the electrolyte and achieve a gap-free battery. Compared to electrocatalytic devices, the current density in PEC systems is related to the current density provided by the photoactive elements, the battery resistance, and the coupling between the optical and electrical components. The typical current density for electrocatalytic processes of industrial interest is above 500 mA/cm², whereas the current density of PEC devices is an order of magnitude lower. Furthermore, electrocatalytic devices can operate continuously, whereas PEC devices need to be operated in the presence of sunlight; this requires their design to focus on low-cost manufacturing to accommodate intermittent operation, rather than traditional considerations related to the efficiency of converting solar energy into chemical energy. In terms of effectiveness and mechanism, PEC is essentially the same as electrocatalytic methods; however, PEC is limited by potential and current density. The current density in electrocatalytic devices can reach 1 A/cm², while that in PEC devices is usually two orders of magnitude lower. At the same time, under a decentralized production model, PEC production units need to minimize downstream operations in order to be compatible with the productivity and pressure levels of those units; however, current literature pays little attention to these aspects, and PEC devices are often studied as standalone elements, without consideration for their integration within the value chain.

04 Series/Pairwise Electrocatalytic Reactions: Series/pairwise electrocatalytic reactions hold great potential in the field of bio-based processes. Their main advantage lies in their ability to enable process intensification and the development of low-carbon processes; they also allow the use of renewable energy. Furthermore, by generating redox reactants on-site (such as hydrogen equivalents and reactive oxygen species), it is possible to avoid the costs associated with producing reducing agents or oxidizing agents. However, despite this technology having been known for many years, there are still no commercial applications to date, mainly due to various difficulties that need to be overcome: one of these is the need to identify suitable electrocatalysts, which must exhibit high Faradaic selectivity and stability at high current densities in order to address typical issues such as electrode contamination or leaching ； Secondly, it is necessary to achieve a proper matching between the anodic and cathodic reactions, in order to ensure balance in aspects such as reaction rate, electron flow, and H⁺/OH⁻ flow. Current research often focuses on a single electrode side (especially the cathode), with insufficient attention paid to the synergistic use of both sides. When research focuses on cathodic reactions such as CO₂RR or HER, the oxygen evolution reaction (OER) is a typical anodic reaction. However, OER has slow kinetics and requires a high overpotential; therefore, alternative oxidation reactions, including the oxidation of wastewater, are often explored. Recently, there has also been interest in reactions that are energetically favorable and have fast kinetics in order to accelerate the process. However, although some alternative reactions (such as using hydrogen oxidation to improve the performance of ammonia electrosynthesis, or using nitrates instead of N2 for ammonia reduction) can enhance certain properties, they are not ideal solutions for improving the technical economic viability and sustainability of this technology; further research is needed to focus on the relevant value chains and real-world industrial examples. Some EU projects have explored series/paired electrocatalytic reactions; for example, the TERRA project investigated using the temperature difference between batteries to match anodic and cathodic reactions, while the PERFORM project attempted to pair glucose oxidation with hydrodeoxidation to produce adipic acid. Furthermore, pairing CO₂RR with the electrooxidation (OOR) of organic (bio-based) chemicals is also an emerging approach; for example, the oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) in combination with CO₂RR not only reduces the overpotential but also yields high-value chemicals. Overall, however, there are still many shortcomings in research in this field, such as a lack of systematic studies on the overall battery reaction, some integration processes not yet being demonstrated through electrocatalysis, high costs for downstream processing, and a weak underlying scientific foundation, all of which require further exploration and optimization.

05 Electrocatalytic-mediated synthesis. Electrocatalytic-mediated synthesis (also known as indirect electrolysis) is a method that is well-established in organic electrosynthesis, but has not yet been widely adopted in other fields of electrocatalysis. Its core principle is to achieve indirect conversion of the substrate by using a redox mediator as an electron transfer agent – when it is difficult for the substrate to undergo a direct redox reaction, the redox mediator can first transfer electrons with the electrode and then react with the substrate, thereby facilitating the desired conversion. This method has various advantages: first, it can eliminate the kinetic inhibition of heterogeneous electron transfer between the electrode and the substrate, thereby reducing the reaction overpotential ； Secondly, redox mediators can exhibit selectivity different from that of direct electrolysis, or even higher selectivity ； Thirdly, since the reaction takes place at a lower potential, it is possible to reduce or avoid the deactivation of the electrodes caused by high potentials ； Fourth, it can avoid side reactions that tend to occur at high potentials, thereby improving the purity of the product. However, electrocatalytic-mediated synthesis also has significant limitations; its additional costs (especially those associated with downstream separation and the recovery of redox mediators) are considerable for the production of bulk commodities and chemicals. In organic electro-synthesis, the profit margin from high-value chemicals can cover these costs, but in large-scale industrial production, cost control becomes significantly more difficult. The commonly used redox mediators vary depending on the type of reaction; in anodization, specific transition metal compounds are often used, while for cathodic reactions, transition metal complexes can be employed. Overall, electrocatalytic-mediated synthesis, as a potential efficient conversion strategy, still requires further exploration and optimization in light of specific application scenarios. In particular, breakthroughs are needed in areas such as cost reduction and improving the efficiency of medium recycling in order to expand its application across a wider range of electrocatalytic fields.

06 The Key to Achieving Electrochemistry: The vision of electrochemistry is to address societal challenges such as sustainable development, carbon-neutral production, and a circular carbon economy through technologies like electrocatalysis, thereby driving a transformation in the production methods of chemicals and energy toward more sustainable and low-carbon approaches. Realizing the future of electrochemistry is an important approach to addressing societal challenges, with the core lying in establishing entirely new models for the production of chemicals and energy through technologies such as electrocatalysis. This future model needs to achieve three main goals: first, to develop resilient development models that minimize reliance on and constraints imposed by external resources ； Second, establish carbon-neutral or even carbon-negative production systems to reduce environmental impact ； Third is to achieve a carbon circular economy that goes beyond fossil fuels. Electrocatalysis, as a key technology, plays a central role in driving this transformation; therefore, how to prioritize the integration of various electrocatalytic reactions and overcome the limitations of current research in order to achieve a shift from traditional thermal catalysis to electrochemistry is an issue that requires careful exploration. Realizing the future of electrochemistry requires efforts in various areas. At the research level, it is necessary to overcome current limitations and explore the potential of electrocatalysis from a broader perspective, such as expanding the range of reactions and enhancing the synergistic use of different reactions, while also giving importance to research in systems engineering ； At the technical level, it is necessary to improve the design of electrocatalytic reactors, develop advanced ones, and optimize operating conditions to reduce costs ； At the theoretical level, it is necessary to establish a unified theory of electrochemistry and electrocatalysis to guide the design of new electrocatalysts. Furthermore, it is necessary to incorporate emerging technologies and methods, such as 3D printing, to accelerate the scaling up of electrocatalytic technologies, facilitate their transition from laboratory research to industrial application, and ultimately build a sustainable future for electrochemistry. 07 Conclusions and Perspectives Although research on electrocatalysis is gaining momentum, its potential has not yet been fully exploited, with numerous challenges in terms of technology, cost, and research directions. Currently, the transition from the laboratory to industrial application is slow, partly due to a lack of understanding of the many possibilities of electrocatalysis. In the future, it is necessary to expand the scope of research, explore the potential of emerging reactions such as CO₂ reduction and nitrogen fixation, and enhance the synergistic use of different reactions ； New evaluation models need to be developed to accurately measure the impact of electrocatalysis in entirely new scenarios ； Cross-disciplinary collaboration should also be employed to foster creative research, transform theoretical achievements into practical applications, promote the widespread use of electrocatalytic technologies, and help build a sustainable and carbon-cycling future for electrochemistry.

【Ten Years of Rapid Development in Chemical Equipment】Another major advancement from 2581 to 2025! ! World’s first flight of a 2-ton eVTOL for offshore oil platforms https://bbs.hcbbs.com/thread-5697979-1-1.html (Source: Haichuan Chemical Industry Forum)

【Ten Years of Rapid Development in Chemical Engineering Equipment】2584–2025: Bridging the gap in China’s field of ultra-thick hydrogen-resistant steels; Wugang’s 195 mm thick Q345R(R-HIC) steel plates resistant to hydrogen-induced cracking. https://bbs.hcbbs.com/thread-5698095-1-1.html (Source: Haichuan Chemical Industry Forum)