Low Energy Utilization Research Articles

In situ synthesized S-type heterojunction Bi2O2CO3/CuBi2O4 enable efficient NIR light-driven H2O2 activation for water purification

Hydrogen peroxide (H2O2) was the most commonly used oxidant in advanced oxidation processes to degrade emerging organic pollutants. However, photoactivation of H2O2 by catalysts had the problems of narrow pH application range and low solar energy utilization rate. Herein, the Bi2O2CO3/CuBi2O4 heterojunction photocatalyst was in-situ synthesized, which could activate H2O2 under NIR radiation to degrade organic pollutants and complex heavy metal pollutants. Both in-situ irradiation XPS spectra and DFT supported the S-type charge transfer mechanism. Driven by the IEF and bending band, photogenerated electrons were transferred from Bi2O2CO3 to CuBi2O4, which inhibited the recombination of carriers and promoted the activation of H2O2. The activation rate constant of CBO-2/Vis/H2O2 system for H2O2 was 0.0403 min−1, which was 36.6 times that of the original BOC. This work provided new systematic insights into H2O2 activation by S-scheme heterojunction and had implications for wastewater treatment.

Hybrid nanogenerators based on PVDF/6H–SiC composite film with enhanced mechanical energy utilization efficiency

The flexible polyvinylidene difluoride (PVDF)/6H–SiC composite films are fabricated to overcome the natural brittleness of hexagonal SiC. Yet the electrical output of the piezoelectric nanogenerator (PENG) based on the composite film needs to be further improved. Here, PENG and hybrid nanogenerator exploiting both triboelectric and piezoelectric effects (T-PENG) based on PVDF/6H–SiC composite films are assembled. The PENG based on the PVDF/15 wt% 6H–SiC composite film shows the open circuit voltage (Voc) of 16.81 V. The T-PENG achieves the bridge rectified voltage of 65.70 and 136.58 V when subjected to the external force of 1.1 and 4.9 N, indicating 3.91 and 7.39 times the output of the PENG under the same force, which is the highest value compared with the reported nanogenerators based on SiC and SiC composites. This work breaks through the limitation of low mechanical energy utilization efficiency of film-based PENG and provides a feasible way to enhance the electrical output of nano power sources.

Research on Low-Carbon, Energy-Saving Sintering Process with Uniform Temperature for Drill Bits

A low-carbon and energy-saving sintering process with uniform temperature distribution has been developed to address several issues associated with the sintering of drill bits in medium-frequency furnaces, namely, the large circumferential temperature differences, uneven heating of the mold, and low energy utilization. Theoretical calculations indicated that the output energy of the conventional drill bit sintering process was 12.7 kW·h, with an energy loss of 8.84 kW·h. The low-carbon sintering process achieved an output energy of 4.2 kW·h, with an energy loss of only 0.26 kW·h. Consequently, the energy utilization rates for the two processes were 30.4% and 93.8%, respectively. It was observed through the experiment that when sintering 76/49 mm drill bits at insulation temperatures of 900 °C and 1080 °C, the circumferential temperature differences in the mold were 43.7 °C and 48 °C, respectively, in the conventional drill bit sintering process. In contrast, the circumferential temperature differences in the mold were reduced to 8.7 °C and 11.3 °C, respectively, in the low-carbon and energy-saving sintering process with uniform temperature. This indicates that the average circumferential temperature difference in the mold can be reduced by 81.61% at 900 °C and by 76.46% at 1080 °C, leading to improved drill bit quality.

Synergistic effect of superhydrophilic skeleton decorated with hierarchical micro/nanostructures and graphene oxide on solar evaporation

Solar evaporation is considered as a sustainable and environment-friendly technology to produce the fresh water. However, the significant improvement in the solar evaporation efficiency is limited by the low energy utilization rate of evaporator, unreasonable design and/or complex manufacturing processes. Herein, the innovative solar vapor generator has been manufactured by the simple chemical oxidation and physical precipitation, consisting of the copper foam and graphene oxide (GO) as matrix. The copper foam skeleton of the innovative solar evaporator decorated with micro/nanostructure limits the heat to the evaporation interface for in-situ heating, effectively generating the vapor and minimizing the heat loss. The superhydrophilic structure and oxygen-containing groups of GO play a positive role in promoting the continuous wetting and water transport. The wetting state of unfilled pores provides sufficient space for the diffusion of vapor from the evaporation interface. Findings demonstrate that the evaporation rate and efficiency of superhydrophilic copper foam solar vapor generator deposited with 1.5 mg/mL GO (SHiCF-GO-1.5) are 1.25 kg/(m2·h) and 88.9% under 1-sun irradiation, respectively. The innovative solar evaporator makes full use of skeleton to expand solar absorption and evaporation interfaces to the whole 3D structure, playing a dominant role for enhancing solar evaporation efficiency.

Prospective study of a novel heat pump system with solar energy spectral beam splitting

Renewable solar energy as a resource for carbon emissions reduction, its application and promotion are hindered by low energy utilization efficiency. Photovoltaic modules mainly convert solar energy into electricity only in the high-frequency spectrum band. In order to achieve a high coefficient of performance, a novel heat pump system with solar energy spectral beam splitting was developed by matching the energy grade and heat pump cycle operating conditions. This also addresses the issue that the conventional heat pump system cannot supply heat efficiently and stably in the cold region of North China. Theoretical investigations were carried out on the distribution of parameters of energy load and efficiency. Compared with conventional PV modules, solar energy utilization with spectral beam splitting, which divides solar energy into the low-frequency spectrum for thermal energy collection and the high-frequency range for power generation, ensures high power production efficiency and utilization efficiency by the cascade thermal and electric energy exploitation in the proposed novel heat pump system. Partial thermal energy is used to provide the hot water, and the rest is upgraded by an ejector-based heat pump system to meet the space heating requirements. Therefore, the novel heat pump system achieves the combined supply of space heating, hot water, and electricity with high solar energy utilization efficiency through active energy conversion and thermal energy recovery. The goal of creating a structure with zero electric power consumption appears promising. When compared to the typical single PV system's (30.7%) efficiency, the suggested system's overall energy usage efficiency (up to 81.7%) is noticeably higher. In extreme cold areas, the performance superiority of the novel system is more prominent.

High-efficiency and low-carbon inactivation of UV resistant bacteria in reclaimed water by flow-through electrode system (FES)

With the increasingly serious shortage of water resources globally, it has been paid more attention on how to secure the biosafety of reclaimed water and other non-traditional water sources. However, the 3 most applied disinfection technics, which are chlorine, ultraviolet (UV), and ozone disinfection, all have their disadvantages of selecting undesired bacteria and low energy utilization efficiency. Electrode disinfection is a promising solution, but the current electrode disinfection process still needs to be optimized in terms of the use conditions of the configuration reactivation. In this paper, we built a flow electrode system (FES). To evaluate the disinfection techniques more precisely, we isolated ultraviolet-resistant bacteria (URB) bacteria from the water of the full-scale water plant and tested the disinfection performance of FES and UV. The inactivation rate, reactivation potential, and energy consumption were analyzed. FES could inactivate 99.99 % of the URB and cause irreversible damage to the residual bacteria. FES could make all bacteria strains apoptosis in the subsequent 24 h of storage after alternating pulse current (APC) treatment, 3 V, within 27.7 s. Besides, the energy consumption of FES is about 2 orders lower than that of UV disinfection under the same inactivation rate. In summary, APC-FES is an efficient and low-carbon alternative for future water disinfection, which could achieve the ideal disinfection effect of a high inactivation rate, no reactivation, and low energy consumption.

Study on Energy Flow Characteristics of Solar–Gas Combined Heating System for Settling Tank of Oilfield

Heating furnaces fueled by fossil fuels are commonly utilized in oilfields to provide heat to the settling tank, which heats the layer of crude oil. However, this traditional heating method consumes a significant amount of oil and gas resources, resulting in low energy utilization and environmental pollution. As the water content of the extracted crude oil increases over time, the operating costs of the settling tanks also continue to increase. Therefore, it is crucial to develop and implement clean and efficient heating technologies to facilitate the efficient operation of settling tanks. This paper proposes a solar–gas combined heating technology for settling tanks. A simulation model for the solar–gas combined heating system for the settling tank is constructed, considering the overall perspective of the system. The simulation model analyzes the impact of the control strategy for the oil collection period of the settling tank on the system performance. This analysis covers various aspects including the heat collection of the solar collector, the heat supply of the gas boiler, and the heat storage and release of the phase-change heat storage tank. The results demonstrate that when the oil collection cycle is Scheme E (4:00–8:00), the collector achieves the highest annual cumulative heat collection, the gas boiler provides the lowest annual total heat supply, and the phase-change heat storage tank exhibits the highest heat storage and release efficiency. Over the course of the system’s 15 year service life, the settling tank solar–gas combined heating system saves 727,988.69 MJ of energy annually, resulting in total energy-saving costs of CNY 397,007. The dynamic investment payback period is estimated at 9.14 years, and the system reduces CO2 emissions by 753,069.8 kg.

The construction of S-scheme heterostructure in ultrathin WS2/Zn3In2S6 nanosheets for enhanced photocatalytic hydrogen evolution

Metal sulfide based photocatalysts are considered to be economic, environmentally benign and renewable. The rapid recombination of photogenerated electrons and holes and low solar energy utilization efficiency, however, remain a huge bottleneck. Herein, two-dimensional/two-dimensional (2D/2D) S-scheme WS2/Zn3In2S6 heterostructure with ultrathin nanosheets intervening between neighboring component has been designed. The large and intimate S-scheme heterojunctions facilitate interfacial charge separation/transfer and optimize the available redox potential. Besides, the ultrathin 2D/2D heterostructure ensures large specific surface area, maximized interface synergistic interaction, and effective exposure of surface active sites. As a result, 2 wt% WS2/Zn3In2S6 exhibits a high photocatalytic hydrogen production rate of 30.21 mmol·g−1·h−1 under simulated solar light illumination with an apparent quantum efficiency of 56.1% at 370 nm monochromatic light, far exceeding pristine Zn3In2S6 (6.65 mmol·g−1·h−1). Our work underscores the significance of integrating morphology engineering and S-scheme heterojunctions design for high-efficient and low-cost photocatalysts.

Thermodynamic and economic evaluation on a novel cogeneration system based on energy sectionalized closed utilization method

Based on the characteristics of temperature evolution during steam energy release, the idea of energy sectionalized conversion is proposed, and a dual-stage organic Rankine cycle (DORC) that can be respectively matched with varying temperature process and constant temperature process of the steam is constructed to enhance effective energy input from the energy input end. Besides, an absorption heat pump (AHP) is considered as the bottom cycle to recycle all exhaust vapor waste heat of DORC to achieve closed utilization of heat energy. The coupling of DORC and AHP to form a DORC-AHP cogeneration system can simultaneously improve the energy conversion efficiency of medium–low temperature steam from both the energy quality and quantity perspectives. Energy, exergy and economic assessments are carried out to disclose the superiority of the new energy utilization method. Compared with the singular-stage organic Rankine cycle (SORC) and DORC, the thermal efficiency of DORC-AHP is enhanced by 84.74% and 84.15%, the exergy efficiency is enhanced by 10.48% and 8.36%, and the exergy loss is decreased by 912.15 kW and 687.25 kW as the saturation temperature of the steam, superheat degree and mass fraction of R600 are 132℃, 40℃ and 0.10. Furthermore, there is an optimal saturation temperature and superheat degree of the steam to make the exergy efficiency of new cogeneration system the highest. Meanwhile, there is an optimal steam saturation temperature that enables AHP to assimilate all the exhaust vapor waste heat of DORC with the lowest driving heat source flow rate ratio between AHP and DORC. In addition, compared with the SORC and DORC, the exergy cost of new cogeneration system is decreased by 0.0007 $/kWh and 0.0006 $/kWh, multiple of investment cost (MOIC) is increased by 5.02 and 5.35, and dynamic payback period (DPP) is shortened by 2.46 years and 3.00 years. The DPP and MOIC of DORC-AHP system are both gradually close to those of SORC and DORC with the rise of electricity price. The results indicate that the new energy sectionalized closed conversion pattern demonstrates distinct superiority in the thermal and economic performance. The study achievement can lay a theoretical foundation for improving medium–low temperature steam energy utilization degree.

Shovel-loading cooperative control of loader under typical working conditions

The difference in power demand and the driver’s operation in various operation stages make the loader have the problem of low energy utilization. Changeable operating objects and drastically changing loads have exacerbated the difficulty of energy-saving research in different operating stages of loaders. Therefore, based on identifying the operation stage and analyzing the load characteristics under typical working conditions of the loader, this paper proposes a shovel-loading cooperative control strategy. Specifically, the Drag Reduction Insertion (DRI) in the shoveling stage is realized based on learning the driving intention. Based on different operation stages, the load characteristics of different materials for shovel-loading are deeply analyzed, and the prediction research of the power output characteristics of the power unit is carried out. The shovel-loading cooperative control solves the problem of the poor economy caused by different power requirements in different operation stages and significantly reduces the impact of the driver’s operating experience.

Development and testing of self-swelling cartridge for use as stemming material in open-pit blasting —A quarry case study

This paper examines the problems of low explosive energy utilization rate and poor blasting efficiency due to the use of unsuitable stemming materials in open-pit blasting. A self-swelling cartridge stemming plug is developed for use in quarry and open pit blast hole stemming. The self-swelling cartridge stemming development and testing procedures are presented in the paper. Various amounts of magnesium-aluminum mix activator are added to a self-swelling agent to determine the optimum amount of activator that results in the quick initiation of hydration reaction of the self-swelling agent to achieve complete reaction within acceptable field production stemming time. The laboratory test results show that the reaction time of the self-swelling cartridge increases with activator content. The expansion pressure of the self-swelling cartridge and the shear force at its interface with the blasthole wall for different diameters of cartridges increase with the increase of the cartridge diameter. Thus, from the indoor test results, the self-swelling cartridge in a saturated state effectively sealed the simulated blast hole within about 1 h, with an expansion pressure of 26.3–49.8 MPa and a shear force of 113.4 kN. Field tests were conducted to compare the effects of the self-swelling cartridge and drill cuttings as stemming materials in a limestone quarry using high-speed photography and fragmentation analysis. The results show that the self-swelling cartridge stemming can effectively prevent blast hole blowout compared to the drill cuttings stemming. This is shown in the field fragmentation analysis comparing from zones using the self-swelling cartridge to the drill cutting stemming zone fragmentation. It is concluded that use of self-swelling cartridge stemming results in better blast fragmentation at lower cost and higher safety than drill cuttings stemming in open pit blasting.

Research on low‐carbon evaluation of clean energy use in rural residential buildings based on Analytic Hierarchy Process method

AbstractAs an important part of the construction industry, rural residential buildings are characterized by low energy utilization, unreasonable structure, and low consumption level, so it is particularly important to study the low carbon transformation and evaluation system. In this study, the coefficient of variation method was used to identify the important factors affecting the low‐carbon transformation of rural residential buildings, and the evaluation system of low‐carbonization of rural residential buildings was determined by Analytic Hierarchy Process (AHP), and the system was used in a rural residential building low‐carbonization evaluation study. The results show that “Energy utilization,” “Envelope structure,” and “Economic factors” have obvious influence on the low carbonization of buildings, with the weights of 36.4%, 24.5%, and 19.5%, respectively. Among the secondary indicators, the top four weightings are “clean energy utilization rate” (0.152), “external wall insulation system” (0.090), “window performance” (0.088), and “electricity consumption” (0.084), which are the most critical factors influencing the low carbonization level of clean energy utilization in rural residential buildings. Finally, based on the constructed low‐carbonization evaluation system, we propose targeted solution strategies to provide a theoretical basis for establishing an effective assessment system for the low‐carbonization of clean energy in rural residential buildings.

Thermal Management System of Vapor Compression for Downhole Instrument

Abstract As the depth of oil and gas exploration increases, downhole electronics face the threat of high-temperature failure. At present, passive cooling technology has the problem of short working time, while active cooling technology has low energy utilization. This paper presents a thermal management system of vapor compression with a combination of active and passive cooling. The system uses insulation materials to isolate the high-temperature environment, thermally conductive silicone grease to strengthen the heat exchange in the evaporator, and vapor compression refrigeration cycles to absorb internal heat. The coefficient of performance (COP), exergy destruction and exergy efficiency of octane, nonane, and cyclohexane as refrigerants were examined, and the effects of different insulation materials on refrigeration performance were studied from both theoretical and numerical perspectives. The results showed that cyclohexane exhibited the best cooling capacity with a COP of 1.296 and a exergy efficiency of 49.21%. The thermal management system cooling performance is optimal when the insulation material is a vacuum flask, with an effective cooling capacity of 121.7 W.

Solar interfacial regeneration performance of different solutions for liquid desiccant cooling system

A liquid desiccant cooling system (LDCS) is a promising energy-saving air-conditioning system with the advantages of being driven by low-grade heat and excellent humidity control ability. However, the problems of high energy consumption and low energy utilization efficiency of its regenerator limit its further development. To improve, a novel solar interfacial regeneration (SIR) method is proposed. The method can convert solar energy into heat and locate the heat at the evaporation interface so that the regenerator has high energy utilization efficiency. Experimental studies were carried out on different liquid desiccants. The results show that the thermal regeneration efficiency of this method is 2.6 to 2.9 times that of the conventional thermal regeneration method. LiBr solution has the best regeneration performance, but MgCl2 and CaCl2 are cheaper. Considering energy utilization efficiency and economic cost, the mixed desiccant may be a better choice. These advances could make SIR-based LDCS a potential contender for future air-conditioning systems.

Strong photo-thermal coupling effect boosts CO2 reduction into CH4 in a concentrated solar reactor

This study is dedicated to solving the problems of low energy utilization and low yield in the conventional photocatalytic CO2 reduction process. Herein, we constructed a novel concentrated solar (light) reactor and enabled the titanium foam-based monolithic photocatalyst TF@TNT/0.4CoOx-0.1CuO to improve the solar energy utilization efficiency and CO2 conversion rate by concentrating light and its thermal effect. We found that the yield of CH4 increased up to 220 times (from 0.53 µmol/cm2 to 116.4 µmol/cm2) when the light intensity of the reactor was increased from 400 mW/cm2 to 4266 mW/cm2 (10.6 times). Meanwhile, the solar-to-fuel conversion efficiency was improved up to 0.35% in the concentrated solar (light) reactor. We further investigated the origin of the photothermal coupling effect with concentrated light through the electrochemical and photochemical measurements. It shows that the concentrated light can further lower the reaction barrier (from 41.62 to 31.51 kJ/mol) and the induced photothermal coupling effect could significantly increase the yield. This provides a valuable strategy for the efficient and environmentally friendly utilization of CO2 using solar energy.

Analyzing the Factors Influencing the Adoption of Integrated Pest Management (IPM) Technology in Cotton in Rajasthan

Background: The model of sustainable agriculture mostly emphasizes on enhancing the efficacy of agrochemical usage by the implementation of Integrated Pest Management (IPM) technology, substitution of various inputs and practices with effective alternative technologies involving low energy utilization and plant/animal integration. Following the sustainable approach towards agriculture, a research has been conducted in the state of Rajasthan to identify the major factors that influence the adoption of IPM technology in Cotton. Cotton being the major crop of Sri Ganganagar and Hanumangarh districts for kharif season had an average area of 2.39 lakh hectares and average production of 7.44 lakh bales that constituted 51 per cent and 52 per cent of total area and production of Rajasthan, respectively during last five years ending 2016-17. Methods: On the basis of pest management strategy, farmers in the area were classified into three categories viz. farmers following conventional practice, farmers following IPM practice and farmers following both the practices, for the research. The purpose of the study was to identify the factors influencing adoption of IPM technology in the study area. A total of nine metric socio-economic variables of three groups of a total sample of 90 farmers from both the districts were taken for the study for the crop year 2017-18. The data were analyzed through suitable statistics: linear discriminant analysis and two-step cluster analysis. Result: It was found that ‘years of experience in current practice followed’, ‘number of workshops attended for current practice’, ‘years of education’, ‘years of experience in agriculture’ and ‘number of trainings attended for current practice’ are the major variables that discriminated among the three group of practices followed by the farmers of the study area. Among the selected significant discriminating factors, ‘higher education’, ‘higher number of workshops attended for current practice’ and ‘higher number of trainings attended for current practice’ were found to be the major influencing factors towards the adoption of IPM technology among the cotton growers in the study area. This study would facilitate the stakeholders involved in the dissemination of IPM technology as a measure for sustainable agriculture.

Cycle Characteristics of a New High-Temperature Heat Pump Based on Absorption–Compression Revolution

A large amount of the waste heat generated during industrial production is not used, which leads to a low energy utilization rate. The recovery of industrial waste heat using heat pumps has the advantages of low energy consumption, high efficiency, safety, and environmental protection. Industrial waste heat has a wide temperature distribution range. Traditional absorption and compression heat pumps can only work in a narrow temperature range due to the thermodynamic cycle, the thermal properties of the working medium, the temperature and pressure resistance of the compressor, and other factors; they cannot simultaneously meet the requirements of a “high heating temperature” and “wide temperature-range heat transfer”. To solve the above problems, this paper proposes a high-temperature heat pump unit based on a coupled cycle of absorption and compression, which can recover low-temperature steam and 50 °C waste heat and produce hot water at 110–130 °C. EES software is used for the mathematical modeling and simulation analysis of the heat pump unit. The results show that, when the driving steam temperature is 140 °C and the waste heat temperature is 50 °C, the heating temperature can reach 110~130 °C and the COP of the system can reach 4.22. Increasing the waste heat outlet temperature and the condensation temperature of the absorption cycle strengthens the COP of the coupled cycle; meanwhile, increasing the evaporation temperature and heating temperature of the absorption cycle reduces the COP of the coupled cycle. The results of this study significantly broaden the operating temperature range and heating temperature of electric heat pumps; our findings therefore have essential research significance for improving energy efficiency in industrial fields.

An Overview of Current and Prognostic Trends on Synthesis, Characterization, and Applications of Biobased Silica

Silica has shown numerous applications in different fields such as environmental, biomedical, agriculture, and even in chemical processing. However, due to high energy-intensive and cost-effective issues, researchers show interest to replace the conventional methods with biobased environmentally-friendly techniques for biosilica production from renewable biomass sources. Generally, silica is found to be available in amorphous and crystalline structures. For commercial purposes, silica is produced from alkyl orthosilicates ore that consists of polyethlydiorthosilicate, tetraethyl ortothosilicate, and tetramethyl orthosilicate. Another form of silica, silica gel, is produced from the selected resources of biomass, such as palm tree, wheat straw, maize leaves, teff straw, sugarcane bagasse, rice husk, rice straw, sugarcane leaf, oat husk, bamboo leaf, and corn cob. The production of biobased silica gel from agricultural residues is found to be a sustainable which receives a significant attention that can be replaced with inorganic-based silica gel for environmental concerns. Based on this context, there is a huge look for developing a process to produce biobased silica and silica gel from biomass resources with low energy utilization as promising alternatives to conventional methods. Keeping in view, current trends and methods for synthesis, the characterization of biobased silica and silica gel, as well as its wide prognostic applications were focused on a comprehensive review.

Energy-Efficient Data Aggregation and Cluster-Based Routing in Wireless Sensor Networks Using Tasmanian Fully Recurrent Deep Learning Network with Pelican Variable Marine Predators Algorithm

One of the major significant problems in the existing techniques in Wireless Sensor Networks (WSNs) is Energy Efficiency (EE) because sensor nodes are battery-powered devices. The energy-efficient data transmission and routing to the sink are critical challenges because WSNs have inherent resource limitations. On the other hand, the clustering process is a crucial strategy that can rapidly increase network lifetime. As a result, WSNs require an energy-efficient routing strategy with optimum route election. These issues are overcome by using Tasmanian Fully Recurrent Deep Learning Network with Pelican Variable Marine Predators Algorithm for Data Aggregation and Cluster-Based Routing in WSN (TFR-DLN-PMPOA-WSN) which is proposed to expand the network lifetime. Initially, Tasmanian Fully Recurrent Deep Learning Network (TFR-DLN) is proposed to elect the Optimal Cluster Head (OCH). After OCH selection, the three parameters, trust, connectivity, and QoS, are optimized for secure routing with the help of the Pelican Variable Marine Predators Optimization Algorithm (PMPOA). Finally, the proposed method finds the minimum distance among the nodes and selects the best routing to increase energy efficiency. The proposed approach will be activated in MATLAB. The efficacy of the TFR-DLN- PMPOA-WSN approach is assessed in terms of several performances. It achieves higher throughput, higher packet delivery ratio, higher detection rate, lower delay, lower energy utilization, and higher network lifespan than the existing methods.

MOF-on-MOF-Derived Hollow Co3 O4 /In2 O3 Nanostructure for Efficient Photocatalytic CO2 Reduction.

The photocatalytic transformation of carbon dioxide (CO2 ) into carbon-based fuels or chemicals using sustainable solar energy is considered an ideal strategy for simultaneously alleviating the energy shortage and environmental crises. However, owing to the low energy utilization of sunlight and inferior catalytic activity, the conversion efficiency of CO2 photoreduction is far from satisfactory. In this study, a MOF-derived hollow bimetallic oxide nanomaterial is prepared for the efficient photoreduction of CO2 . First, a unique ZIF-67-on-InOF-1 heterostructure is successfully obtained by growing a secondary Co-based ZIF-67 onto the initial InOF-1 nanorods. The corresponding hollow counterpart has a larger specific surface area after acid etching, and the oxidized bimetallic H-Co3 O4 /In2 O3 material exhibits abundant heterogeneous interfaces that expose more active sites. The energy band structure of H-Co3 O4 /In2 O3 corresponds well with the photosensitizer of [Ru(bpy)3 ]Cl2 , which results in a high CO yield of 4828±570µmolh-1 g-1 and stable activity over a consecutive of six runs, demonstrating adequate photocatalytic performance. This study demonstrates that the rational design of MOF-on-MOF heterostructures can completely exploit the synergistic effects between different components, which may be extended to other MOF-derived nanomaterials as promising catalysts for practical energy conversion and storage.