Enabling heterogeneous catalysis to achieve carbon neutrality: Directional catalytic conversion of CO_(2) into carboxylic acids

The increase in anthropogenic carbon dioxide(CO_(2))emissions has exacerbated the deterioration of the global environment,which should be controlled to achieve carbon neutrality.Central to the core goal of achieving carbon neutrality is the utilization of CO_(2) under economic and sustainable conditions.Recently,the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO_(2) into carboxylic acids,which can effectively alleviate CO_(2) emissions and create high-value chemicals.The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO_(2) conversion into carboxylic acids through photo-,electric-,and thermal catalysis.Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level,inspiring the preparation of high-performance catalysts.In addition,theoretical calculations,advanced technologies,and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity.Finally,challenges and prospects are provided for the future development of this field.It is hoped that this review will contribute to a deeper understanding of the conversion of CO_(2) into carboxylic acids and inspire more innovative breakthroughs.

A review on electrocatalytic CO_(2) conversion via C-C and C-N coupling

Electrochemical C-C and C-N coupling reactions with the conversion of abundant and inexpensive small molecules,such as CO_(2) and nitrogencontaining species,are considered a promising route for increasing the value of CO_(2) reduction products.The development of high-performance catalysts is the key to the both electrocatalytic reactions.In this review,we present a systematic summary of the reaction systems for electrocatalytic CO_(2) reduction,along with the coupling mechanisms of C-C and C-N bonds over outstanding electrocatalytic materials recently developed.The key intermediate species and reaction pathways related to the coupling as well as the catalyst-structure relationship will be also discussed,aiming to provide insights and guidance for designing efficient CO_(2) reduction systems.

The Capture and Catalytic Conversion of CO_(2) by Dendritic Mesoporous Silica-Based Nanoparticles

Dendritic mesoporous silica nanoparticles own three-dimensional center-radial channels and hierarchical pores,which endows themselves with super-high specific surface area,extremely large pore volumes,especially accessible internal spaces,and so forth.Dissimilar guest species(such as organic groups or metal nanoparticles)could be readily decorated onto the interfaces of the channels and pores,realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications.As adsorbents and catalysts,dendritic mesoporous silica nanoparticles-based materials have experienced nonignorable development in CO_(2)capture and catalytic conversion.This comprehensive review provides a critical survey on this pregnant subject,summarizing the designed construction of novel dendritic mesoporous silica nanoparticles-based materials,the involved chemical reactions(such as CO_(2)methanation,dry reforming of CH_(4)),the value-added chemicals from CO_(2)(such as cyclic carbonates,2-oxazolidinones,quinazoline-2,4(1H,3H)-diones),and so on.The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials(such as SBA-15 or MCM-41),and the corresponding reaction mechanisms have been thoroughly revealed.It is sincerely expected that the in-depth discussion could give materials scientists certain inspiration to design brand-new dendritic mesoporous silica nanoparticles-based materials with superior capabilities towards CO_(2)capture,utilization,and storage.

Potential of eNose Technology for Monitoring Biological CO_(2) Conversion Processes

Electronic nose(eNose) is a modern bioelectronic sensor for monitoring biological processes that convert CO_(2) into valueadded products, such as products formed during photosynthesis and microbial fermentation. eNose technology uses an array of sensors to detect and quantify gases, including CO_(2), in the air. This study briefly introduces the concept of eNose technology and potential applications thereof in monitoring CO_(2) conversion processes. It also provides background information on biological CO_(2) 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 CO_(2) conversion processes. eNose-predicted measurements were observed to be completely aligned with biological parameters for R~2 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 CO_(2) conversion processes. We also explore the potential benefits of employing this technology vis-à-vis monitoring biological CO_(2) conversion processes, such as increased reaction efficiency and reduced costs versus traditional monitoring methods. Moreover, future directions and challenges of using this technology in CO_(2) capture and conversion have been discussed. Overall, we believe this study would contribute to developing new and innovative methods for monitoring biological CO_(2) conversion processes and mitigating climate change.

Plasma-based CO_(2) conversion:How to correctly analyze the performance?

Plasma-based CO_(2)conversion is promising for carbon capture and utilization.However,inconsistent reporting of the performance metrics makes it difficult to compare plasma processes systematically,complicates elucidating the underlying mechanisms and compromises further development of this technology.Therefore,this critical review summarizes the correct definitions for gas conversion in plasma reactors and highlights common errors and inconsistencies observed throughout literature.This is done for pure CO_(2)splitting,dry reforming of methane and CO_(2)hydrogenation.We demonstrate that the change in volumetric flow rate is a critical aspect,inherent to these reactions,that is often not correctly taken into account.For dry reforming of methane and CO_(2)hydrogenation,we also demonstrate inconsistent reporting of energy efficiency,and through numerical examples,we show the significance of these deviations.Furthermore,we discuss how to measure changes in volumetric flow rate,supported by data from two experimental examples,showing that the sensitivity inherent to a standard component and a flow meter is essential to consider when deriving the performance metrics.Finally,some general recommendations and good practices are provided.This paper aims to be a comprehensive guideline for authors,to encourage more consistent calculations and stimulate the further development of this technology.

Direct detection of a single[4Fe-4S]cluster in a tungsten-containing enzyme:Electrochemical conversion of CO_(2) into formate by formate dehydrogenase

The conversion of CO_(2) into fuels and valuable chemicals is one of the central topics to combat climate change and meet the growing demand for renewable energy.Herein,we show that the formate dehydrogenase from Clostridium ljungdahlii(ClFDH)adsorbed on electrodes displays clear characteristic voltammetric signals that can be assigned to the reduction and oxidation potential of the[4Fe-4S]^(2+/+)cluster under nonturnover conditions.Upon adding substrates,the signals transform into a specific redox center that engages in catalytic electron transport.ClFDH catalyzes rapid and efficient reversible interconversion between CO_(2) and formate in the presence of substrates.The turnover frequency of electrochemical CO_(2) reduction is determined as 1210 s^(-1) at 25℃ and pH 7.0,which can be further enhanced up to 1786 s^(-1) at 50℃.The Faradaic efficiency at−0.6 V(vs.standard hydrogen electrode)is recorded as 99.3%in a 2-h reaction.Inhibition experiments and theoretical modeling disclose interesting pathways for CO_(2) entry,formate exit,and OCN−competition,suggesting an oxidation-state-dependent binding mechanism of catalysis.Our results provide a different perspective for understanding the catalytic mechanism of FDH and original insights into the design of synthetic catalysts.

Electrochemical urea synthesis by co-reduction of CO_(2) and nitrate with Fe^(Ⅱ)-Fe^(Ⅲ)OOH@BiVO_(4) heterostructures

Traditional urea synthesis under harsh conditions is usually associated with high energy input and has aroused severe environmental concerns.Electrocatalytic C-N coupling by converting nitrate and CO_(2) into urea under ambient conditions represents a promising alternative process.But it was still limited by the strong competition between nitrate electrochemical reduction(NO_(3)ER) and CO_(2) electrochemical reduction(CO_(2)ER).Here,Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-n heterostructures are constructed through hydrothermal synthesis and exhibited superior performance toward urea electrosynthesis with NO_(3)~-and CO_(2) as feedstocks.The optimized urea yield and Faradaic efficiency over Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-2 can reach13.8 mmol h^(-1) g^(-1) and 11.5% at-0.8 V vs.reversible hydrogen electrode,which is much higher than that of bare FeOOH(3.2 mmol h^(-1) g^(-1) and 1.3%),pristine BiVO_(4)(2.0 mmol h^(-1) g^(-1) and 5.4%),and the other Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-n(n=1,3,5) heterostructures.Systematic experiments have verified that BiVO_(4)and FeOOH are subreaction active sites towards simultaneous CO_(2)ER and NO_(3)ER,respectively,achieving co-activation of CO_(2) and NO_(3)~-on Fe^(Ⅱ)-Fe~ⅢOOH@BiVO_(4)-2.Moreover,the urea synthesis via the ^(*)CO and NO*intermediates and C-N coupling was confirmed by the in situ Fourier transform infrared spectroscopy.This work not only alleviates the CO_(2) emission and nitrate pollution but also presents an efficient catalyst for synergistic catalysis towards sustainable urea synthesis.

Meta-analysis of CO_(2) conversion,energy efficiency,and other performance data of plasma-catalysis reactors with the open access PIONEER database

This paper brings the comparison of performances of CO_(2)conversion by plasma and plasma-assisted catalysis based on the data collected from literature in this field,organised in an open access online database.This tool is open to all users to carry out their own analyses,but also to contributors who wish to add their data to the database in order to improve the relevance of the comparisons made,and ultimately to improve the efficiency of CO_(2)conversion by plasma-catalysis.The creation of this database and database user interface is motivated by the fact that plasma-catalysis is a fast-growing field for all CO_(2)conversion processes,be it methanation,dry reforming of methane,methanolisation,or others.As a result of this rapid increase,there is a need for a set of standard procedures to rigorously compare performances of different systems.However,this is currently not possible because the fundamental mechanisms of plasma-catalysis are still too poorly understood to define these standard procedures.Fortunately however,the accumulated data within the CO_(2)plasma-catalysis community has become large enough to warrant so-called“big data”studies more familiar in the fields of medicine and the social sciences.To enable comparisons between multiple data sets and make future research more effective,this work proposes the first database on CO_(2)conversion performances by plasma-catalysis open to the whole community.This database has been initiated in the framework of a H_(2)0_(2)0 European project and is called the“PIONEER Data Base”.The database gathers a large amount of CO_(2)conversion performance data such as conversion rate,energy efficiency,and selectivity for numerous plasma sources coupled with or without a catalyst.Each data set is associated with metadata describing the gas mixture,the plasma source,the nature of the catalyst,and the form of coupling with the plasma.Beyond the database itself,a data extraction tool with direct visualisation features or advanced filtering functionalities has been developed and is available online to the public.The simple and fast visualisation of the state of the art puts new results into context,identifies literal gaps in data,and consequently points towards promising research routes.More advanced data extraction illustrates the impact that the database can have in the understanding of plasma-catalyst coupling.Lessons learned from the review of a large amount of literature during the setup of the database lead to best practice advice to increase comparability between future CO_(2)plasma-catalytic studies.Finally,the community is strongly encouraged to contribute to the database not only to increase the visibility of their data but also the relevance of the comparisons allowed by this tool.

A simple hydroxypyridine ionic liquids for conversion of CO_(2)into quinazoline-2,4(1H,3H)-diones under atmospheric conditions

The transformation of CO_(2)into high value-added product is a promising pathway for utilizing CO_(2).However,the process tends to require harsh reaction conditions owing to CO_(2)chemical inertness.Designing a high efficiency catalytic system with environmentally benign characteristic are important determinants.In this work,protic ionic liquids[TMG][2-OPy]were prepared via one-step neutralization between 1,1,3,3-tetramethylguanidine and 2-hydroxypyridine,applying to the domain of synthesizing quinzoline-2,4(1 H,3H)-diones from CO_(2)and 2-aminobenzontiles without any solvent or metal,achieving the yield of 97%at 90℃for 8 h under atmospheric.A series of substrates with good to acceptable yield were detected,revealing the generality and universality of the catalyst.Furthermore,the system could be facilely reused for at least six runs,retaining the yield of 94%.A preliminary kinetic equation is calculated with the activation energy of 68 kJ·mol^(-1),and a plausible reaction mechanism was put forward.This study highlights that the[TMG][2-OPy]enables to activate CO_(2)carboxylation efficiently.

超高选择性CO_(2)光还原为乙醇的CuNi异核双原子催化剂的精准设计

利用光催化还原技术将CO_(2)定向转化为乙醇(CO_(2)-乙醇)是解决日益严重的环境污染和能源危机的理想途径之一.然而,CO_(2)分子的高化学惰性以及C-C耦合反应的高化学能垒导致目前CO_(2)-乙醇转化反应的产率和选择性较低.因此,设计构建能够快速活化CO_(2)分子并同时促进C-C耦合的光催化材料具有重要研究意义.尽管已有研究表明,Cu+物种在促进C-C耦合方面具有一定优势,但其在催化反应过程中的不稳定性限制了其实际应用.基于上述认识,本文通过理论模拟预测发现,相比于Cu单原子,CuNi异核双原子(CuNi HDAs)不仅在CO_(2)活化及C-C耦合方面更具优势,而且能够有效锚定并固化Cu+物种.因此,本文设计了一种三步合成策略,精准地将Cu单原子锚定在(Ni,Zr)-UiO-66-NH2材料的Ni位上,合成了以CuNi HDAs为活性位点的Cu-(Ni,Zr)-UiO-66-NH2光催化材料.在可见光照射下,Cu-(Ni,Zr)-UiO-66-NH2表现出较好的催化CO_(2)-乙醇转化活性,其乙醇的产率和选择性分别达到~3218μmol·gCu^(-1)·h^(-1)和97.3%.光谱分析和密度泛函理论计算结果表明,Cu-(Ni,Zr)-UiO-66-NH2材料较好的光催化性能来源于CuNi HDAs特殊的电子结构.首先,CuNi HDAs通过CuNi-O界面化学键与吸光组分(Ni,Zr)-UiO-66-NH2相连,利用界面Cu-Ni-O键作为快速电子传输通道,CuNi HDAs能够富集到足够的光生电子用于涉及12电子的CO_(2)-乙醇转化反应,使得乙醇产率大幅提升.其次,Cu,Ni和O三种原子由于电子亲核能的差异,导致CuNi HDAs的电子分布呈现不对称性.这种不对称的电子结构能有效诱导CO_(2)分子的极化,打破其结构的对称性,从而显著降低CO_(2)分子的活化能.再次,相比于Cu单原子,CuNi HDAs对*CO中间体的吸附能力更强,这不仅增强了活性位点表面*CO中间体的覆盖度,还抑制CO的生成,为C-C耦合创造了充分条件.最后,由于Cu-Ni双活性位电子密度的差异,CuNi HDAs表面的C-C耦合反应势能较低,有利于*OCCHO中间体的快速生成,从而使乙醇产物的选择性大幅提升.综上,本文以理论计算模拟为指导,以UiO-66-NH2材料为基底,成功设计并制备了一种具有不对称电子结构的CuNi HDAs光催化材料,实现了高选择性CO_(2)光还原为乙醇.研究表明,CuNi HDAs的不对称结构在促进分子活化和降低C-C耦合反应能垒中起关键作用,同时促进了光生电子在CuNi HDAs活性位的富集.本文的研究结果为在原子尺度上设计并合成高性能的CO_(2)还原光催化剂提供了实验和理论参考.

多种构型超临界CO_(2)循环热力学解构分析与参数优化

新型超临界CO_(2)(S-CO_(2))循环可通过流程改良提高效率,构型复杂多样。为了直观阐明各种流程改良措施对循环效率提升的作用机制,本文将预压缩、后压缩、再压缩、间冷、再热等五种构型的S-CO_(2)循环解构为若干热功转换过程,建立各解构过程与循环效率之间的关联方程,进而开展流程参数优化。研究结果表明,预压缩、后压缩和再压缩方案均是通过增加压缩耗功,减少吸热量实现循环效率提升,其中再压缩方案效果最优,再压缩流量优化后循环效率提高5.1%;采用部分间冷方案,可有效降低压缩功耗,同时避免高品位热量贬值,间冷压力优化后循环效率提高2.2%;再热方案在不改变压缩耗功的前提下,增加透平出功,再热压力优化后循环效率提高1.9%;最后,循环联用再压缩、间冷和再热三种节能措施,可使效率提高9.3%。

弱碱性吸收剂碳捕集及CO_(2)富液生物再生性能

碳捕集转化一体化工艺能利用CO_(2)转化过程同步实现CO_(2)富液再生,有望降低碳捕集转化整体成本。为评价生物甲烷化与碳捕集耦合的可行性,首先,在填料塔中考察了以4.2 g/L NaHCO_(3)、6 g/L Na_(2)CO_(3)、微生物营养液配制的弱碱性吸收剂(pH=10)对模拟烟气中CO_(2)的吸收性能;其次,在厌氧瓶内利用生物甲烷化过程对CO_(2)富液开展5个周期的循环再生试验。结果表明,填料塔气体流量≤1.0 L/min时,随液体流量增加,所有试验组CO_(2)去除率逐渐上升并能稳定在80%以上,该填料塔液体流量宜≤0.9 L/min;不同气体流量(0.4~1.2 L/min)下填料塔体积总传质系数基本稳定在17~19 mol/(h·kPa·m^(3));CO_(2)吸收导致吸收液中NaHCO_(3)增加、Na_(2)CO_(3)减少,二者变量比值在1.2~1.9。气体流量为0.6 L/min、液体流量为0.7 L/min时,在维持80%以上CO_(2)去除率的前提下,该弱碱性吸收剂可循环使用6次,此时活性组分CO_(3)^(2-)利用率达89.5%,形成的CO_(2)富液中总无机碳量为0.127 mol/L,pH为8.82,能为生物甲烷化微生物提供适宜的生长环境。CO_(2)富液循环生物再生试验表明,每次再生后的吸收剂CO_(2)吸收量基本稳定在69.6~78.6 mmol/L,且再生期间CH 4产生过程具有良好的重复性;再生试验后,Firmicutes、Actinobacteriota等耐碱性门水平细菌得到一定富集;氢营养型产甲烷菌在再生前后古菌属中占比均接近99%,但再生试验期间弱碱性环境导致Methanobrevibacter相对丰度降低了19.5%,unclassified_f_Methanobacteriaceae增加了18.7%。初步证实了碳捕集耦合生物甲烷化工艺的可行性。

CO_(2)加氢制甲醇Cu/CeO_(2)催化剂实验研究

考察了第二金属Ni改性对CO_(2)加氢制甲醇Cu/CeO_(2)催化剂活性的影响,并通过XRD、BET、XPS、H_(2)-TPR等手段对改性前后催化剂结构进行了表征。结果表明:金属负载量为20%时,Cu/CeO_(2)的比表面积最大;Cu与Ni质量比为3∶1时,催化剂碱度最大,氧空位含量最高,Cu-Ni协同作用最强;该催化剂在反应温度240℃、反应压力3 MPa、液时空速2400 mL/(g·h)、H_(2)与CO_(2)体积比为3∶1时催化CO_(2)加氢制甲醇效果较优,CO_(2)转化率为18.5%,甲醇时空产率为40.43 g/(kg·h)。

利用光驱动的生物杂合系统实现CO_(2)转化生产化学品

太阳能作为清洁能源之一,为缓解化石燃料枯竭和温室气体排放等问题提供了一种高效、经济、可持续的解决方案.自然界中的植物和光合微生物通过自身的光合系统收集并转化太阳能,从而生产生物燃料和生物化学品.然而,由于自然光合系统存在光吸收范围相对较窄、光生电子在传输过程中易损耗等问题,限制了太阳能到化学品的转化效率.为了解决上述难题,科研人员模仿自然光合作用中的关键部分,探索构建人工光合系统,相关研究引起了广泛关注.本文通过将碲化镉量子点(CdTe QDs)与大肠杆菌(E.coli)相耦合,构建了一种光驱动无机-生物杂合系统(IBPHS),用于捕获太阳能并驱动CO_(2)转化合成高价值化学品.该系统主要由光催化模块和生物催化模块组成.在光催化模块中,通过生物合成CdTe QDs进行光能捕获,并将其转化为电子.通过敲除E.coli的Cd2+外排蛋白(ZNTA)编码基因,实现了E.coli胞内Cd2+过量积累.通过“时空耦合”方式,并借助共聚焦显微镜、高分辨率透射电镜和X射线能谱分析,确认了CdTe QDs在E.coli胞内的组装合成.利用紫外-可见分光光度计研究了光催化模块对光子的吸收能力.结果表明,光催化模块的吸收峰位于400-420 nm.利用瞬时光电流,评估了光催化模块的光生电子能力.实验发现,该模块可以产生0.07μA光电流,表明完成了光催化模块的构建.在生物催化模块中,将光催化模块产生的电子用于还原NAD+再生NADH.采用NADH生物传感器,分析了E.coli胞内NADH含量,结果表明,在蓝光照射下E.coli胞内NADH含量比黑暗条件下提高了5.1倍.在此基础上,通过表达NADH依赖型乳酸脱氢酶(LDH)将丙酮酸还原为乳酸,在蓝光光照下乳酸积累量达到了0.44 g/L,而黑暗条件下无乳酸积累,从而验证了生物催化模块的有效性.基于光催化模块和生物催化模块,进一步组装构建了IBPSH,用于驱动CO_(2)还原合成甲酸和丙酮酸.在蓝光照射下,IBPHS能够合成0.65 g/L甲酸和0.18 g/L丙酮酸,其CO_(2)利用速率分别达到51.98 mg/gDCW/h和21.92 mg/gDCW/h,超过了光合细菌.综上所述,本文利用光催化模块与生物催化模块相耦合的方式,组装构建了一种新型的人工光合系统,实现了光驱动CO_(2)还原合成高附加值化学品,为理性设计材料-生物杂合系统提供了借鉴,同时也为挖掘绿色生物制造潜力、开发太阳能化学制造平台提供参考.

硅纳米结构阵列:光热CO_(2)催化的新兴平台

人口的快速增长和高能源需求产业造成了严重的环境问题。太阳能等替代性的清洁能源对于缓解能源危机和温室效应至关重要。光催化是一种很有前途的方法,但它在转化率、效率和规模化方面存在局限性。光热催化则结合了光化学和光热效应,是在温和条件下有效催化化学反应的新概念。近年来,与传统的光热催化剂相比,硅纳米结构阵列在光热CO_(2)还原反应中表现出独特的催化性能优势。作为一种平台,它表现出优异的光收集能力、高比表面积以及多样化的材料复合选择。本文综述了光热催化CO_(2)转化的概念和原理,硅纳米结构阵列的功能,以及利用硅纳米结构阵列在光热催化CO_(2)转化方面的最新进展,最终将为高性能纳米结构阵列光热CO_(2)催化剂的发展方向提供指导。

Cu/TiO_(2) Photocatalysts for CO_(2) Reduction: Structure and Evolution of the Cocatalyst Active Form

Extensive work on a Cu-modified TiO_(2) photocatalyst for CO_(2) reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV-vis diff use refl ectance spectroscopy, high-resolution transmis- sion electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu 0 , Cu^(+) , and Cu^(2+) ), the content of which depends on the TiO_(2) calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO_(2) calcined at 700℃ and modified with 5 wt% copper, the activity of which is 22 μmol/(h·g cat ) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO_(2) was gradually converted into Cu_(2) O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO_(2) did not undergo any trans- formation during the reaction.

非均相单宁酸-锆介孔材料制备及其CO_(2)环加成反应催化性能

CO_(2)和环氧化物的环加成反应是一种有效且可持续的CO_(2)化工转化策略,其产品环碳酸酯在锂离子电池、高分子材料等领域具有广泛应用。其中环氧化物的开环被认为是该反应的关键步骤,因此构筑具有高效环氧化物吸附活化位点的催化剂至关重要。本文通过单宁酸与锆离子的配位作用,“一锅法”制备同时含有锆金属中心作为Lewis酸位点和酚羟基作为氢键作用位点的非均相单宁酸-锆介孔材料TA-Zr-2。XPS和环氧丙烷TPD-MS结果表明,与同为锆基多孔材料的UiO-66相比,TA-Zr-2的锆金属中心具有更强的Lewis酸性,对环氧丙烷具有更强的吸附活化作用。在TA-Zr-2的基础上通过冷冻干燥优化处理得到了具有更大比表面积和合适孔体积的TA-Zr-2-FD材料,25℃下催化性能提升1倍,24h的碳酸丁烯酯收率达97.6%。本文使用简单绿色的制备方法,构建了具有较大比表面积的单宁酸-锆介孔材料,锆Lewis酸位点和酚羟基氢键位点的耦合使其具有良好的环氧化物吸附活化作用,利于环氧化物的开环,使得该催化剂在25℃下表现出良好的CO_(2)环加成反应催化性能。

微生物-电极修饰及影响电合成转化CO_(2)过程的研究进展

微生物电合成(microbial electrosynthesis,MES)是一种利用电活性微生物摄取胞外电子,将CO_(2)或有机废料转化为可再生化学品的技术。首先,文中阐述了电极的改性方式,碳基材料以其多样的形态、优异的化学稳定性和高比表面积等优点,在电极改性中发挥着重要作用,其主要是通过提供更多的微生物附着点和增强电子传递效率改善MES;而非碳基材料如金属材料等,因其优异的导电性和催化活性,则被广泛用于提升电极性能,其作用机制在于加速电极上的催化反应和促进特定产品的生成。其次,从电活性微生物角度入手,揭示了在电极材料修饰和微生物细胞修饰上的共同点都是能够提高微生物的电子传递能力,不同点在于微生物细胞修饰可以直接作用于微生物的生理和遗传特性,以增强其电子传递能力和底物转化效率。此外,分析了纳米材料与高附加值产品之间的关系,认为合理选择和制备电极材料及微生物细胞修饰策略,对于提高MES系统的效率和产物选择性至关重要。最后,对MES技术面临的挑战和未来的研究方向进行了展望。

三维碳凝胶基催化剂在CO_(2)催化转化中的应用研究进展

随着化石能源的过度消耗和CO_(2)的大量排放,能源与环境问题日渐严重。将温室气体CO_(2)催化转化为高附加值的燃料和化学品,是解决能源短缺和环境问题的理想途径。光催化、电催化和热催化是CO_(2)催化转化的常用策略。在各种催化过程中,普遍存在载流子复合率高、催化剂团聚和催化剂回收困难等问题。三维碳凝胶因具有高导电性、高比表面积、高孔隙率、高CO_(2)吸附性、资源丰富和环境友好等特点,被应用于各类催化反应体系中。重点介绍了CO_(2)催化转化的理论基础以及光催化、电催化和热催化CO_(2)的原理、三维碳凝胶基催化剂在三类CO_(2)催化转化体系中的最新进展,并提出了三维碳凝胶基催化剂未来发展的机遇和挑战。

Electrochemical reduction of carbon dioxide to produce formic acid coupled with oxidative conversion of biomass

Electrochemical reduction of CO_(2)(CO_(2)RR)has become a research hot spot in recent years in the context of carbon neutrality.HCOOH is one of the most promising products obtained by electrochemical reduction of CO_(2) due to its high energy value as estimated by market price per energy unit and wide application in chemical industry.Biomass is the most abundant renewable resource in the natural world.Coupling biomass oxidative conversion with CO_(2)RR driven by renewable electricity would well achieve carbon negativity.In this work,we comprehensively reviewed the current research progress on CO_(2)RR to produce HCOOH and coupled system for conversion of biomass and its derivatives to produce value-added products.Sn-and Bi-based electrocatalysts are discussed for CO_(2)RR with regards to the structure of the catalyst and reaction mechanisms.Electro-oxidation reactions of biomass derived sugars,alcohols,furan aldehydes and even polymeric components of lignocellulose were reviewed as alternatives to replace oxygen evolution reaction(OER)in the conventional electrolysis process.It was recommended that to further improve the efficiency of the coupled system,future work should be focused on the development of more efficient and stable catalysts,careful design of the electrolytic cells for improving the mass transfer and development of environment-friendly processes for recovering the formed formate and biomass oxidation products.