Muhammad AwaisSyed Muhammad Zaigham Abbas NaqviSami Ullah KhanM.Ijaz Khan...
381-394页
查看更多>>摘要：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 technol-ogy 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.
查看更多>>摘要：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/CoMoyOx catalysts(RuO2/CoMoyOx/TM)with heterogeneous struc-tures.By optimizing the ratio of Co to Mo,RuO2/CoMo2Ox/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/CoMoyOx/TM can be maintained for 50 h at 100 mA/cm2,and a water electrolyzer with RuO2/CoMo2Ox/TM as anode can operate for 40 h at 100 mA/cm2,suggesting the remarkable OER durability of RuO2/CoMoyOx/TM in acidic electrolyte.Owing to the heterogeneous interface between CoMo2Ox 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.
查看更多>>摘要：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 兀-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 treat-ment 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.
查看更多>>摘要：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 TARGE 169 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.
查看更多>>摘要：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.
查看更多>>摘要：The presence of iron(Fe)has been found to favor power generation in microbial fuel cells(MFCs).To achieve long-term power production in MFCs,it is crucial to effectively tailor the release of Fe ions over extended operating periods.In this study,we developed a composite anode(A/IF)by coating iron foam with cellulose-based aerogel.The concentration of Fe ions in the anode solution of A/IF anode reaches 0.280 μg/mL(Fe2+vs.Fe3+=61％:39％)after 720 h of aseptic primary cell operation.This value was significantly higher than that(0.198 μg/mL,Fe2+vs.Fe3+=92％:8％)on uncoated iron foam(IF),indicating a continuous release of Fe ions over long-term operation.Notably,the resulting MFCs hybrid cell exhibited a 23％reduction in Fe ion concentration(compared to a 47％reduction for the IF anode)during the sixth testing cycle(600-720 h).It achieved a high-power density of 301±55 mW/m2 at 720 h,which was 2.62 times higher than that of the IF anode during the same period.Furthermore,a sedimentary microbial fuel cell(SMFCs)was constructed in a marine environment,and the A/IF anode demonstrated a power density of 103±3 mW/m2 at 3240 h,representing a 75％improvement over the IF anode.These findings elucidate the significant enhancement in long-term power production performance of MFCs achieved through effective tailoring of Fe ions release during operation.
查看更多>>摘要：The stacking and aggregation of graphene nanosheets have been obstacles to their application as electrode materials for micro-electronic devices.This study deploys a one-step,scalable,facile electrochemical exfoliation technique to fabricate nitrogen(N)and chlorine(Cl)co-doped graphene nanosheets(i.e.,N-Cl-G)via the application of constant voltage on graphite in a mixture of 0.1 mol/L H2SO4 and 0.1 mol/L NH4C1 without using dangerous and exhaustive operation.The introduction of Cl(with its large radius)and N,both with high electrical negativity,facilitates the modulation of the electronic structure of graphene and creation of rich structural defects in it.Consequently,in the as-constructed supercapacitors,N-Cl-G exhibits a high specific capacitance of 77 F/g at 0.2 A/g and remarkable cycling stability with 91.7％retention of initial capacitance after 20,000 cycles at 10 A/g.Furthermore,a symmetrical supercapacitor assembled with N-Cl-G as the positive and nega-tive electrodes(denoted as N-Cl-G//N-Cl-G)exhibits an energy density of 3.38 Wh/kg at a power density of 600 W/kg and superior cycling stability with almost no capacitance loss after 5000 cycles at 5 A/g.This study provides a scalable protocol for the facile fabrication of high-performance co-doped graphene as an electrode material candidate for supercapacitors.
查看更多>>摘要：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.
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