Noble metal-based intermetallic compounds (IMCs) with ordered atomic arrangements exhibit remarkable electrocatalytic activity owing to their unique crystal and electronic structures. During the past years, great advance has been made in the development of noble metal-based IMCs. Recently, Lu and coworkers reported ultrathin “amorphous/intermetallic” (A/IMC) heterophase PtPbBi nanosheets (NSs) with a thickness of 2.5 ± 0.3 nm. The oxidative etching effect caused by the coexistence of O₂ and Br^‒ ions plays a crucial role in the formation of the IMC and unique two-dimensional structure with irregular shapes and curled edges. This study shows that fabricating an A/IMC heterophase structure with a multimetallic composition can effectively enhance the catalytic performances of noble metal-based electrocatalysts.

The development of high-performance, reproducible carbon (C)-based supercapacitors remains a significant challenge because of limited specific capacitance. Herein, we present a novel strategy for fabricating LaCoO _x and cobalt (Co)-doped nanoporous C (LaCoO _x/Co@ZNC) through the carbonization of Co/Zn-zeolitic imidazolate framework (ZIF) crystals derived from a PVP-Co/Zn/La precursor. The unique ZIF structure effectively disrupted the graphitic C framework, preserved the Co active sites, and enhanced the electrical conductivity. The synergistic interaction between pyridinic nitrogen and Co ions further promoted redox reactions. In addition, the formation of a hierarchical pore structure through zinc sublimation facilitated electrolyte diffusion. The resulting LaCoO _x/Co@ZNC exhibited exceptional electrochemical performance, delivering a remarkable specific capacitance of 2,789 F/g at 1 A/g and outstanding cycling stability with 92% capacitance retention after 3,750 cycles. Our findings provide the basis for a promising approach to advancing C-based energy storage technologies.

Cu-based catalysts have been extensively used in methanol steam reforming (MSR) reactions because of their low cost and high efficiency. ZnO is often used in commercial Cu-based catalysts as both a structural and an electronic promoter to stabilize metal Cu nanoparticles and modify metal–support interfaces. Still, the further addition of chemical promoters is essential to further enhance the MSR reaction performance of the Cu/ZnO catalyst. In this work, CeO₂-doped Cu/ZnO catalysts were prepared using the coprecipitation method, and the effects of CeO₂ on Cu-based catalysts were systematically investigated. Doping with appropriate CeO₂ amounts could stabilize small Cu nanoparticles through a strong interaction between CeO₂ and Cu, leading to the formation of more Cu⁺–ZnO _x interfacial sites. However, higher CeO₂ contents resulted in the formation of larger Cu nanoparticles and an excess of Cu⁺–CeO _x interfacial sites. Consequently, the Cu/5CeO₂/ZnO catalyst with maximal Cu–ZnO interfaces exhibited the highest H₂ production rate of $94\text{.6}{\text{mmol}}_{{\text{H}}_2}{\text{/(g}}_{\text{cat}}\cdot \text{h)}$, which was 1.5 and 10.2 times higher than those of Cu/ZnO and Cu/CeO₂, respectively.

Supercapacitors have emerged as a promising class of energy storage technologies, renowned for their impressive specific capacities and reliable cycling performance. These attributes are increasingly significant amid the growing environmental challenges stemming from rapid global economic growth and increased fossil fuel consumption. The electrochemical performance of supercapacitors largely depends on the properties of the electrode materials used. Among these, iron-based sulfide (IBS) materials have attracted significant attention for use as anode materials owing to their high specific capacity, eco-friendliness, and cost-effectiveness. Despite these advantages, IBS electrode materials often face challenges such as poor electrical conductivity, compromised chemical stability, and large volume changes during charge–discharge cycles. This review article comprehensively examines recent research efforts aiming at improving the performance of IBS materials, focusing on three main approaches: nanostructure design (including 0D nanoparticles, 1D nanowires, 2D nanosheets, and 3D structures), composite development (including carbonaceous materials, metal compounds, and polymers), and material defect engineering (through doping and vacancy introduction). The article sheds light on novel concepts and methodologies designed to address the inherent limitations of IBS electrode materials in supercapacitors. These conceptual frameworks and strategic interventions are expected to be applied to other nanomaterials, driving advancements in electrochemical energy conversion.

Porous metal–organic frameworks (MOFs) have been recently discovered to be efficient catalysts for energy applications and green technologies. Here, we report on a scalable catalytic platform using Cu-based MOFs for electrocatalytic alkaline hydrogen evolution reaction. First, the solvothermal synthesis of Cu-BTC MOFs (BTC = 1,3,5-benzenetricarboxylate) at 85 °C and a 1:60 ligand-to-solvent ratio allowed for minimizing the chemical consumption. Second, the obtained platform demonstrated enhanced electrochemical performance compared with commercially available Cu-based MOFs, with a potential of − 230 versus − 232 eV, logarithm of the current density of − 3.6 versus − 4.2 cm², and electrochemical surface area of 75 versus 25 cm² per cm² of geometric area, respectively. Morphological and Raman analyses also revealed that the high concentration of defects in the obtained submicron Cu-BTC MOFs can contribute to their improved catalytic performance. Thus, our findings pave the way to the low-cost synthesis of energy-efficient MOF-based catalysts for hydrogen production.

Combusting refuse for energy production is promising for their treatment and disposal. However, because of geographical constraints, there has not been a stable model for the energy utilization of refuse in low-oxygen plateau areas. This paper took Lhasa as an example to conduct gasification and incineration experiments on local representative combustible refuse, and relevant energy conversion laws were investigated. Results showed that under gasification and incineration modes, the energy conversion rate of any component of refuse can reach 75% and 85% in low-oxygen plateau areas at temperatures of 450 and 650 °C, respectively, which were 5%–10% lower than those in plain areas. The regional distribution of energy conversion of refuse in Lhasa showed that the energy conversion rate under the gasification mode was 3%–5% lower than that of the incineration mode at 450 and 650 °C. In terms of temperature, the energy conversion rates of refuse were 5%–10% lower at 450 °C than those at 650 °C, but an energy conversion rate of more than 85% can still be achieved. Thus, gasification, incineration, or gasification-assisted secondary incineration at temperatures of at least 450 °C is suitable for energy recovery of refuse in low-oxygen plateau areas.

Cu-based materials are commonly used in electrocatalytic nitrate reduction reactions (NO₃RR). NO₃RR is a “two birds, one stone” approach, simultaneously removing NO₃ ⁻ pollutants and producing valuable ammonia (NH₃). However, the strong coordination between the NO₃ ⁻ intermediate and the catalytic active sites seriously hinders the conversion efficiency. Here, we determined that, through encapsulation strategies, the carbon layer could weaken the NO₃ ⁻ intermediate binding to active sites, resulting in higher NH₃ yields. We experimentally fabricated electrocatalysts, i.e., Cu nanoparticles encapsulating (or loaded on) N-doped carbon nanofibers (NCNFs) called Cu@NCNFs (Cu-NCNFs), using electrostatic spinning. As a result, Cu@NCNFs can achieve NH₃ yields of 17.08 mg/(h·mg_cat) at a voltage of − 0.84 V and a Faraday efficiency of 98.15%. Meanwhile, the electrochemical properties of the Cu nanoparticles on the surface of carbon fibers (Cu-NCNFs) are lower than those of the Cu@NCNFs. The in situ Raman spectra of Cu@NCNFs and Cu-NCNFs under various reduction potentials during the NO₃RR process show that catalyst encapsulation within carbon layers can effectively reduce the adsorption of N species by the catalyst, thus improving the catalytic performance in the nitrate-to-ammonia catalytic conversion process.

In the long term, coal will remain a competitive resource in the thermal power sector, primarily due to its abundant global reserves and low costs. Despite numerous factors, including significant environmental concerns, the global share of coal power generation has remained at 40% over the past four decades. Efficient and clean coal combustion is a high priority wherever coal is used as a fuel. An improved low-power boiler design has been proposed to enhance efficiency during fixed-bed coal combustion. This design reduces harmful emissions into the atmosphere by optimizing parameters and operating modes. In this study, mathematical modeling of gas velocity and temperature distribution during fixed-bed coal combustion was conducted for a conventional grate system and an improved grate-free system. Experimental methods were employed to develop descriptive airflow models in the fixed coal layer, considering nozzle diameter and air supply pressure in the furnace chamber without a grate system. Comparative evaluations of fixed-bed coal combustion rates were performed using an experimental laboratory setup with both grate and grate-free stove systems.

The strategic manipulation of the interaction between a central metal atom and its coordinating environment in single-atom catalysts (SACs) is crucial for catalyzing the CO₂ reduction reaction (CO₂RR). However, it remains a major challenge. While density-functional theory calculations serve as a powerful tool for catalyst screening, their time-consuming nature poses limitations. This paper presents a machine learning (ML) model based on easily accessible intrinsic descriptors to enable rapid, cost-effective, and high-throughput screening of efficient SACs in complex systems. Our ML model comprehensively captures the influences of interactions between 3 and 5d metal centers and 8 C, N-based coordination environments on CO₂RR activity and selectivity. We reveal the electronic origin of the different activity trends observed in early and late transition metals during coordination with N atoms. The extreme gradient boosting regression model shows optimal performance in predicting binding energy and limiting potential for both HCOOH and CO production. We confirm that the product of the electronegativity and the valence electron number of metals, the radius of metals, and the average electronegativity of neighboring coordination atoms are the critical intrinsic factors determining CO₂RR activity. Our developed ML models successfully predict several high-performance SACs beyond the existing database, demonstrating their potential applicability to other systems. This work provides insights into the low-cost and rational design of high-performance SACs.

Electronic nose (eNose) is a modern bioelectronic sensor for monitoring biological processes that convert CO₂ into value-added products, such as products formed during photosynthesis and microbial fermentation. eNose technology uses an array of sensors to detect and quantify gases, including CO₂, in the air. This study briefly introduces the concept of eNose technology and potential applications thereof in monitoring CO₂ conversion processes. It also provides background information on biological CO₂ conversion processes. Furthermore, the working principles of eNose technology vis-à-vis gas detection are discussed along with its advantages and limitations versus traditional monitoring methods. This study also provides case studies that have used this technology for monitoring biological CO₂ conversion processes. eNose-predicted measurements were observed to be completely aligned with biological parameters for R² values of 0.864, 0.808, 0.802, and 0.948. We test eNose technology in a variety of biological settings, such as algae farms or bioreactors, to determine its effectiveness in monitoring CO₂ conversion processes. We also explore the potential benefits of employing this technology vis-à-vis monitoring biological CO₂ conversion processes, such as increased reaction efficiency and reduced costs versus traditional monitoring methods. Moreover, future directions and challenges of using this technology in CO₂ capture and conversion have been discussed. Overall, we believe this study would contribute to developing new and innovative methods for monitoring biological CO₂ conversion processes and mitigating climate change.

Non-precious metal electrocatalysts (such as Fe–N–C materials) for the oxygen (O₂) reduction reaction demand a high catalyst loading in fuel cell devices to achieve workable performance. However, the extremely low solubility of O₂ in water creates severe mass transport resistance in the thick catalyst layer of Fe–N–C catalysts. Here, we introduce silicalite-1 nanocrystals with hydrophobic cavities as sustainable O₂ reservoirs to overcome the mass transport issue of Fe–N–C catalysts. The extra O₂ supply to the adjacent catalysts significantly alleviated the negative effects of the severe mass transport resistance. The hybrid catalyst (Fe–N–C@silicalite-1) achieved a higher limiting current density than Fe–N–C in the half-cell test. In the H₂–O₂ and H₂–air proton exchange membrane fuel cells, Fe–N–C@silicalite-1 exhibited a 16.3% and 20.2% increase in peak power density compared with Fe–N–C, respectively. The O₂-concentrating additive provides an effective approach for improving the mass transport imposed by the low solubility of O₂ in water.

Energy for space vehicles in low Earth orbit (LEO) is mainly generated by solar arrays, and the service time of the vehicles is controlled by the lifetime of these arrays, which depends mainly on the lifetime of the interconnects. To increase the service life of LEO satellites, molybdenum/platinum/silver (Mo/Pt/Ag) laminated metal matrix composite (LMMC) interconnectors are widely used in place of Mo/Ag LMMC and Ag interconnectors in solar arrays. A 2D thermal–electrical–mechanical coupled axisymmetric model was established to simulate the behavior of the parallel gap resistance welding (PGRW) process for solar cells and Mo/Pt/Ag composite interconnectors using the commercial software ANSYS. The direct multicoupled PLANE223 element and the contact pair elements TARGE169 and CONTA172 were employed. A transitional meshing method was applied to solve the meshing problem due to the ultrathin (1 μm) intermediate Pt layer. A comparison of the analysis results with the experimental results revealed that the best parameters were 60 W, 60 ms, and 0.0138 MPa. The voltage and current predicted by the finite element method agreed well with the experimental results. This study contributes to a further understanding of the mechanism of PGRW and provides guidance for finite element simulation of the process of welding with an ultrathin interlayer.

Molecular engineering is a crucial strategy for improving the photovoltaic performance of dye-sensitized solar cells (DSSCs). Despite the common use of the donor–π bridge–acceptor architecture in designing sensitizers, the underlying structure–performance relationship remains not fully understood. In this study, we synthesized and characterized three sensitizers: MOTP-Pyc, MOS₂P-Pyc, and MOTS₂P-Pyc, all featuring a bipyrimidine acceptor. Absorption spectra, cyclic voltammetry, and transient photoluminescence spectra reveal a photo-induced electron transfer (PET) process in the excited sensitizers. Electron spin resonance spectroscopy confirmed the presence of charge-separated states. The varying donor and π-bridge structures among the three sensitizers led to differences in their conjugation effect, influencing light absorption abilities and PET processes and ultimately impacting the photovoltaic performance. Among the synthesized sensitizers, MOTP-Pyc demonstrated a DSSC efficiency of 3.04%. Introducing an additional thienothiophene block into the π-bridge improved the DSSC efficiency to 4.47% for MOTS₂P-Pyc. Conversely, replacing the phenyl group with a thienothiophene block reduced DSSC efficiency to 2.14% for MOS₂P-Pyc. Given the proton-accepting ability of the bipyrimidine module, we treated the dye-sensitized TiO₂ photoanodes with hydroiodic acid (HI), significantly broadening the light absorption range. This treatment greatly enhanced the short-circuit current density of DSSCs owing to the enhanced electron-withdrawing ability of the acceptor. Consequently, the HI-treated MOTS₂P-Pyc-based DSSCs achieved the highest power conversion efficiency of 7.12%, comparable to that of the N719 dye at 7.09%. This work reveals the positive role of bipyrimidine in the design of organic sensitizers for DSSC applications.

We must urgently synthesize highly efficient and stable oxygen-evolution reaction (OER) catalysts for acidic media. Herein, we constructed a series of Ti mesh (TM)-supported RuO₂/CoMo_yO_x catalysts (RuO₂/CoMo_yO_x/TM) with heterogeneous structures. By optimizing the ratio of Co to Mo, RuO₂/CoMo₂O_x/TM with low Ru loading (0.079 mg/cm²) achieves remarkable OER performance (η = 243 mV at 10 mA/cm²) and high stability (300 h @ 10 mA/cm²) in 0.5 mol/L H₂SO₄ electrolyte. The activity of RuO₂/CoMo_yO_x/TM can be maintained for 50 h at 100 mA/cm², and a water electrolyzer with RuO₂/CoMo₂O_x/TM as anode can operate for 40 h at 100 mA/cm², suggesting the remarkable OER durability of RuO₂/CoMo_yO_x/TM in acidic electrolyte. Owing to the heterogeneous interface between CoMo₂O_x and RuO₂, the electronic structure of Ru atoms was optimized and electron-rich Ru was formed. With modulated electronic properties, the dissociation energy of H₂O is weakened, and the OER barrier is lowered. This study provides the design of low-cost noble metal catalysts with long-term stability in an acidic environment.