CO_(2) conversion to solar fuels and chemicals:Opening the new paths

This future article discusses the new prospects and directions of CO_(2)conversion via the photo-electrocatalytic(PEC)route.The second(2nd)generation solar fuels and chemicals(SFs)are generated directly in PEC systems via electrons/protons reactions without forming molecular H_(2)as an intermediate,overcoming the thermodynamics limitations and practical issues encountered for electro-fuels produced by multistep thermocatalytic processes(i.e.CO_(2)conversion with H_(2)coming from water electrolysis).A distributed and decentralized production of SFs requires very compact,highly integrated,and intensified technologies.Among the existing reactors of advanced design(based on artificial leaves or photosynthesis),the integrated photovoltaic plus electrocatalytic(PV-EC)device is the only system(demonstrated at large scale)to produce SFs with high solar-to-fuel(STF)efficiency.However,while the literature indicates STF efficiency as the main(and only)measure of process performance,we remark here the need to refer to productivity(in terms of current density)and make tests with reliable flow PEC systems(with electrodes of at least 5–10 cm^(2))to accelerate the scaling-up process.Using approaches that minimize downstream separation costs is also mandatory.Many limitations exist in PEC systems,but most can be overcome by proper electrode and cell engineering,thus going beyond the properties of the electrocatalysts.As examples of current developments,we present the progress of(i)artificial leaf/tree devices for green H_(2)distributed production and(ii)a PEC device producing the same chemicals at both cathode and anode parts without downstream operations for green solvent distributed production.Based on these developments,future directions,such as producing fertilizers and food components from the air,are outlined.The aim is to provide new ideas and research directions from a personal perspective.

Recent advances in Cu-based nanocomposite photocatalysts for CO_2 conversion to solar fuels

COconversion via photocatalysis is a potential solution to address global warming and energy shortage.Photocatalysis can directly utilize the inexhaustible sunlight as an energy source to catalyze the reduction of COto useful solar fuels such as CO, CH, CHOH, and CHOH. Among studied formulations, Cubased photocatalysts are the most attractive for COconversion because the Cu-based photocatalysts are low-cost and abundance comparing noble metal-based catalysts. In this literature review, a comprehensive summary of recent progress on Cu-based photocatalysts for COconversion, which includes metallic copper, copper alloy nanoparticles（NPs）, copper oxides, and copper sulfides photocatalysts, can be found. This review also included a detailed discussion on the correlations of morphology, structure, and performance for each type of Cu-based catalysts. The reaction mechanisms and possible pathways for productions of various solar fuels were analyzed, which provide insight into the nature of potential active sites for the catalysts. Finally, the current challenges and perspective future research directions were outlined, holding promise to advance Cu-based photocatalysts for COconversion with much-enhanced energy conversion efficiency and production rates.

Semiconductor,molecular and hybrid systems for photoelectrochemical solar fuel production

The paper shortly reviews the basic direct approaches applied in searching for viable solutions to solar fuel production. These are generally distinguished in molecular and semiconductor(non-molecular)systems, however, hybrid strategies, proposed recently, have also been included. The most promising efforts are considered, highlighting key aspects and emerging critical issues. Special attention is paid to aspects such as electrode architecture, device design, and main differences in the scientific vision and challenges to directly produce solar fuels. This overview could be useful to orientate the readers in the wide panorama of research activities concerning water splitting, natural and artificial photosynthesis, and solar fuel production through the identification of common aspects, specialties and potentialities of the many initiatives and approaches that are developing worldwide in this field with the final aim to meet world energy demand.

Electronic/Ionic Conducting Bipolar Membranes for Solar Fuel Production under pH Gradients

The components required for artificial photosynthesis including light absorbers and catalysts are being developed at a rapid rate.In many cases,the anodic and cathodic reactions driven with these systems are optimized for significantly different pH conditions,raising the issue of how they can be made compatible.Recent work from our group has shown that large pH gradients can be maintained during electrolysis using BPM(bipolar membrane)and that electronic/ionic membranes can be used to couple the two half reactions without the use of external wiring and reducing the ohmic drop in the system.This study investigates the properties of composite BPMs designed for artificial photosynthetic devices that require half reactions to operate under different pH conditions.Details of performance as a function of the nature of the composites and methods of creating BPMs are detailed.

Thermogravimetric Analysis of Zirconia-Doped Ceria for Thermochemical Production of Solar Fuel

Developing an efficient redox material is crucial for thermochemical cycles that produce solar fuels (e.g. H2 and CO), enabling a sustainable energy supply. In this study, zirconia-doped cerium oxide (Ce1-xZrxO2) was tested in CO2-splitting cycles for the production of CO. The impact of the Zr-content on the splitting performance was investigated within the range 0 ≤ x < 0.4. The materials were synthesized via a citrate nitrate auto combustion route and subjected to thermogravimetric experiments. The results indicate that there is an optimal zirconium content, x = 0.15, improving the specific CO2-splitting performance by 50% compared to pure ceria. Significantly enhanced performance is observed for 0.15 ≤ x ≤ 0.225. Outside this range, the performance decreases to values of pure ceria. These results agree with theoretical studies attributing the improvements to lattice modification. Introducing Zr4+ into the fluorite structure of ceria compensates for the expansion of the crystal lattice caused by the reduction of Ce4+ to Ce3+. Regarding the reaction conditions, the most efficient composition Ce0.85Zr0.15O2 enhances the required conditions by a temperature of 60 K or one order of magnitude of the partial pressure of oxygen p(O2) compared to pure ceria. The optimal composition was tested in long-term experiments of one hundred cycles, which revealed declining splitting kinetics.

Solar fuel generation over nature-inspired recyclable TiO_(2)/g-C_(3)N_(4)S-scheme hierarchical thin-film photocatalyst

Preparation of efficient photocatalysts with ease of recovery in solar fuel generation is highly desired to achieve carbon neutralization in carbon dioxide(CO_(2))emissions.Inspired from the forest with superior light penetration and fast gas transport,a TiO_(2)/g-C_(3)N_(4)composite nanowire arrays(NAs)film with maximized light utilization is devised.It is achieved by in-situ coating a thin layer of g-C_(3)N_(4)(as the leaf)on the vertically-oriented TiO_(2)arrays(as tree trunks)on Ti foil(as soil).Benefiting from the effective charge separation by S-scheme charge transfer,intimate contact by the in-situ growth as well as the ingenious structure,the composite,readily recyclable,displays exciting performance in photocatalytic CO_(2)reduction.It is beyond doubt that the combination of heterojunction construction and“nature-inspired biomimetic photocatalyst”design promises practical applications and industrial use.

Layered double hydroxide-based photocatalytic materials toward renewable solar fuels production

Photocatalysis is an ideal and promising green technology to drive numerous chemical reactions for valued chemicals production under very mild conditions,thereby providing solutions to global energy and environment issues related to burning fossil fuels.Over the past decade,layered double hydroxides(LDHs),as the members in two-dimensional materials family,have attracted much attention due to their many advantages in photocatalysis,such as facile synthesis,low cost and powerful tunability of composition.In this review,we provide a synthetic overview of recent research advances of LDH-based photocatalysts,with the main discussion of the design strategies to improve their photocatalytic performance,including component control,defect engineering,hybridization,and topological transformation.Structure-performance correlations and tailor-made material synthesis strategies are elaborated to discuss how to realize high-performance LDH-based photocatalysts for three important reactions(i.e.,water splitting,CO_(2)conversion,and N2 reduction)to generate desirable solar fuels.Further,the remaining challenges and future perspectives of LDH-based photocatalysts are summed up,aiming to inspire brand new solutions for pushing forward the development of LDH-based photocatalysis.

Structural and Mechanistic Aspects of Mn-oxo and Co-based Compounds in Water Oxidation Catalysis and Potential Applications in Solar Fuel Production

To address the issues of energy crisis and global warming, novel renewable carbon-free or carbon-neutral energy sources must be identified and developed. A deeper understanding of photosynthesis is the key to provide a solid foundation to facilitate this transformation. To mimic the water oxidation of photosystem II oxygen evolving complex, Mn-oxo complexes and Co-phosphate catalytic material were discovered in solar energy storage. Building on these discoveries, recent advances in solar energy conversion showed a compelling working principle by combing the active Mn-oxo and Co-based catalysts in water splitting with semiconductor heteronanostructures for effective solar energy harnessing. In this review the appealing systems including Mn-oxo tetramer/Nafion, Mn-oxo dimer/TiO2, Mn-oxo oligomer/WO3, Co-Pi/Fe2O3, and Co-Pi/ZnO are summarized and discussed. These accomplishments offer a promising framework and have a profound impact in the field of solar fuel production.

Current dilemma in photocatalytic CO_(2) reduction:real solar fuel production or false positive outcomings?

Solar driven carbon dioxide(CO_(2))recycling into hydrocarbon fuels using semiconductor photocatalysts offers an ideal energy conversion pathway to solve both the energy crisis and environmental degradation problems.However,the ubiquitous presence of carbonaceous contaminants in photocatalytic CO_(2) reduction system and the inferior yields of hydrocarbon fuels raise serious concerns about the reliability of the reported experimental results.Here in this perspective,we focus on the accurate assessment of the CO_(2) reduction products,systemically discuss the possible sources of errors in the product quantification,elaborate the common mistakes spread in the analysis of reaction products obtained in 13CO_(2) labelling experiments,and further propose reliable protocols for reporting the results of these isotopic tracing experiments.Moreover,the challenges and cautions in the precise measurement of O_(2) evolution rate are also depicted,and the amplification of the concentration of O_(2) in photoreactors well above the limit of detection is still demonstrated to be the most effective solution to this troublesome issue.We hope the viewpoints raised in this paper will help to assessment the reliability of the reported data in future,and also benefit the beginners that intend to dive in the photocatalytic CO_(2) reduction area.

Solar fuel from photo-thermal catalytic reactions with spectrum-selectivity： a review

太阳的燃料是精力以后采购的理想之一。相片和热效果的协同作用在相对温和的条件下面导致一条新途径到更高太阳的燃料生产。这份报纸从光谱选择的相片热的合作催化作用为太阳的燃料生产考察不同途径。评论以光谱选择和相片热的催化作用的合作效果，和机制的意思开始。从一个技术观点，然后，很多个试验性或理论的工作被化学反应和使用的牺牲的试剂排序。另外，这些工作基于操作条件，光谱选择，材料，和生产率被总结并且公布。讨论最后与光谱选择有关相片热的催化反应的未来开发被介绍。

Azobenzene‑Based Solar Thermal Fuels:A Review

The energy storage mechanism of azobenzene is based on the transformation of molecular cis and trans isomerization,while NBD/QC,DHA/VHF,and fulvalene dimetal complexes realize the energy storage function by changing the molecular structure.Acting as“molecular batteries,”they can exhibit excellent charging and discharging behavior by converting between trans and cis isomers or changing molecular structure upon absorption of ultraviolet light.Key properties determining the performance of STFs are stored energy,energy density,half-life,and solar energy conversion efficiency.This review is aiming to provide a comprehensive and authoritative overview on the recent advancements of azobenzene molecular photoswitch system in STFs fields,including derivatives and carbon nano-templates,which is emphasized for its attractive performance.Although the energy storage performance of Azo-STFs has already reached the level of commercial lithium batteries,the cycling capability and controllable release of energy still need to be further explored.For this,some potential solutions to the cycle performance are proposed,and the methods of azobenzene controllable energy release are summarized.Moreover,energy stored by STFs can be released in the form of mechanical energy,which in turn can also promote the release of thermal energy from STFs,implying that there could be a relationship between mechanical and thermal energy in Azo-STFs,providing a potential direction for further research on Azo-STFs.

Surface-modified Ag@Ru-P25 for photocatalytic CO_(2) conversion with high selectivity over CH_(4) formation at the solid–gas interface

Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar fuels.A surface-modified Ag@Ru-P25 photocatalyst with H_(2)O_(2) treatment was designed in this study to convert CO_(2) and H_(2)O vapor into highly selective CH4.Ru doping followed by Ag nanoparticles(NPs)cocatalyst deposition on P25(TiO_(2))enhances visible light absorption and charge separation,whereas H_(2)O_(2) treatment modifies the surface of the photocatalyst with hydroxyl(–OH)groups and promotes CO_(2) adsorption.High-resonance transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray absorption near-edge structure,and extended X-ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst,while thermogravimetric analysis,CO_(2) adsorption isotherm,and temperature programmed desorption study were performed to examine the significance of H_(2)O_(2) treatment in increasing CO_(2) reduction activity.The optimized Ag1.0@Ru1.0-P25 photocatalyst performed excellent CO_(2) reduction activity into CO,CH4,and C2H6 with a~95%selectivity of CH4,where the activity was~135 times higher than that of pristine TiO_(2)(P25).For the first time,this work explored the effect of H_(2)O_(2) treatment on the photocatalyst that dramatically increases CO_(2) reduction activity.

Efficient solar-driven CO_(2)-to-fuel conversion via Ni/MgAlO_(x)@SiO_(2)nanocomposites at low temperature

Solar-driven CO_(2)-to-fuel conversion assisted by another major greenhouse gas CH_(4)is promising to concurrently tackle energy shortage and global warming problems.However,current techniques still suffer from drawbacks of low efficiency,poor stability,and low selectivity.Here,a novel nanocomposite composed of interconnected Ni/MgAlOx nanoflakes grown on SiO_(2)particles with excellent spatial confinement of active sites is proposed for direct solar-driven CO_(2)-to-fuel conversion.An ultrahigh light-to-fuel efficiency up to 35.7%,high production rates of H_(2)(136.6 mmol min^(-1)g^(-1))and CO(148.2 mmol min^(-1)g^(-1)),excellent selectivity(H_(2)/CO ratio of 0.92),and good stability are reported simultaneously.These outstanding performances are attributed to strong metal-support interactions,improved CO_(2)absorption and activation,and decreased apparent activation energy under direct light illumination.MgAlO_(x)@SiO_(2)support helps to lower the activation energy of CH^(*) oxidation to CHO^(*) and improve the dissociation of CH_(4)to CH_(3)^(*) as confirmed by DFT calculations.Moreover,the lattice oxygen of MgAlO_(x) participates in the reaction and contributes to the removal of carbon deposition.This work provides promising routes for the conversion of greenhouse gasses into industrially valuable syngas with high efficiency,high selectivity,and benign sustainability.

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。

2023年中国电池市场分析

介绍2023年我国电池的产量及进出口量:电池总产量约609.66亿只,其中锂离子电池约960 GW·h,铅蓄电池约270 GW·h,碱性锌锰电池约147亿只,普通锌锰电池约166亿只,太阳能电池约541.16 GW,燃料电池为5 668堆;电池出口总量333.35亿只,进口总量23.04亿只。讨论我国电池市场发展趋势。

多源分布式换能系统构建理论方法研究与应用

“双碳”背景下分布式换能系统以其在低碳环保方面的显著优势逐渐在集中供热领域得到应用。本文针对分布式换能系统中热泵、太阳能集热器、板式换热器和燃料电池等关键单元提出了单元能耗评价方法,并通过EES软件对各单元进行了热力学建模以定量评价不同单元在不同工况下的经济性,进而提出分布式换能系统的构建方法以获得流程经济性最优化。以此为依据搭建了最优化流程,并以北京地区某小区为例分析了该系统的供暖季性能,最后进行了经济性和碳减排分析。结果表明:室外温度在-10~5℃范围内变化时,该新型分布式换能系统的COP为2.69~4.43,太阳能集热器效率为45.19%~61.87%,燃料电池日发电量为8047.4~32228.0 kW·h;与常规热力站相比,该新型分布式换能系统的运行成本节省率为32.66%~53.92%,碳减排率为69.07%~73.29%。

Electrocatalytic conversion of CO_2 to liquid fuels using nanocarbon-based electrodes

Recent advances on the use of nanocarbon-based electrodes for the electrocatalytic conversion of gaseous streams of CO2 to liquid fuels are discussed in this perspective paper. A novel gas-phase electrocatalytic cell, different from the typical electrochemical systems working in liquid phase, was developed. There are several advantages to work in gas phase, e.g. no need to recover the products from a liquid phase and no problems of CO2 solubility, etc. Operating under these conditions and using electrodes based on metal nanoparticles supported over carbon nanotube （CNT） type materials, long C-chain products （in particular isopropanol under optimized conditions, but also hydrocarbons up to C8-C9） were obtained from the reduction of CO2. Pt-CNT are more stable and give in some cases a higher productivity, but Fe-CNT, particular using N-doped carbon nanotubes, give excellent properties and are preferable to noble-metal-based electrocatalysts for the lower cost. The control of the localization of metal particles at the inner or outer surface of CNT is an importact factor for the product distribution. The nature of the nanocarbon substrate also plays a relevant role in enhancing the productivity and tuning the selectivity towards long C-chain products. The electrodes for the electrocatalytic conversion of CO2 are part of a photoelectrocatalytic （PEC） solar cell concept, aimed to develop knowledge for the new generation artificial leaf-type solar cells which can use sunlight and water to convert CO2 to fuels and chemicals. The CO2 reduction to liquid fuels by solar energy is a good attempt to introduce renewables into the existing energy and chemical infrastructures, having a higher energy density and easier transport/storage than other competing solutions （i.e. H2）.

全氧燃烧玻璃料方的设计

太阳能玻璃因其作为光伏产业的关键材料,其生产过程中的能效提升和节能环保成为研究的重点。通过分析全氧燃烧窑炉泡沫层较厚问题,结合行业标准JC/T2001-2009《太阳电池用玻璃》规定,提出一种太阳能玻璃料方设计,提供参考和借鉴。

Feasibility Study for a Solar-Energy Stand-Alone System: (S.E.S.A.S.)

The present study is aimed to serve a small community living on Stand-Alone Solar-Energy (S.A.S.E.S) system. As a basis for the study 1 cubic meter of hydrogen is to be produced by electrolysis in 5 hrs that requires energy input of 5 KW-hr. The proposed system consists of the following main components: photovoltaic module, water electrolyzer and fuel cell. Solar hydrogen production by water electrolysis is described and design parameters are specified. Economic feasibility of the proposed system is evaluated. The projected cost of hydrogen is calculated and found to be 5 cents/ft3.