Stabilizing Zinc Anode through Ion Selection Sieving for Aqueous Zn-Ion Batteries.

Uncontrollable dendrite growth and corrosion induced by reactive water molecules and sulfate ions (SO42-) seriously hindered the practical application of aqueous zinc ion batteries (AZIBs). Here we construct artificial solid electrolyte interfaces (SEIs) realized by sodium and calcium bentonite with a layered structure anchored to anodes (NB@Zn and CB@Zn). This artificial SEI layer functioning as a protective coating to isolate activated water molecules, provides high-speed transport channels for Zn2+, and serves as an ionic sieve to repel negatively charged anions while attracting positively charged cations. The theoretical results show that the bentonite electrodes exhibit a higher binding energy for Zn2+. This demonstrates that the bentonite protective layer enhances the Zn-ion deposition kinetics. Consequently, the NB@Zn//MnO2 and CB@Zn//MnO2 full-battery capacities are 96.7 and 70.4 mAh g-1 at 2.0 A g-1 after 1000 cycles, respectively. This study aims to stabilize Zn anodes and improve the electrochemical performance of AZIBs by ion-selection sieving.

In Situ Constructing Metal-Organic Complex Interface Layer Using Biomolecule Enabling Stabilize Zn Anode.

Aqueous zinc-ion batteries (ZIBs) are considered as a promising candidate for next-generation large-scale energy storage due to their high safety, low cost, and eco-friendliness. Unfortunately, commercialization of ZIBs is severely hindered owing to rampant dendrite growth and detrimental side reactions on the Zn anode. Herein, inspired by the metal-organic complex interphase strategy, the authors apply adenosine triphosphate (ATP) to in situ construct a multifunctional film on the metal Zn surface (marked as ATP@Zn) by a facile etching method. The ATP-induced interfacial layer enhances lipophilicity, promoting uniform Zn2+ flux and further homogenizing Zn deposition. Meanwhile, the functional interlayer improves the anticorrosion ability of the Zn anode, effectively suppressing corrosion and hydrogen evolution. Consequently, the as-prepared ATP@Zn anode in the symmetric cell exhibits eminent plating/stripping reversibility for over 2800 h at 5.0 mA cm-2 and 1 mAh cm-2. Furthermore, the assembled ATP@Zn||MnO2 full cells are investigated to evaluate practical feasibilities. This work provides an efficient and simple strategy to prepare stabilized Zn anode toward high-performance ZIBs.

Enhancing Zinc Electrode Stability Through Pre-Desolvation and Accelerated Charge Transfer via a Polyimide Interface for Zinc-Ion Batteries.

Aqueous zinc-based energy storage devices possess superior safety, cost-effectiveness, and high energy density; however, dendritic growth and side reactions on the zinc electrode curtail their widespread applications. In this study, these issues are mitigated by introducing a polyimide (PI) nanofabric interfacial layer onto the zinc substrate. Simulations reveal that the PI nanofabric promotes a pre-desolvation process, effectively desolvating hydrated zinc ions from Zn(H2O)6 2+ to Zn(H2O)4 2+ before approaching the zinc surface. The exposed zinc ion in Zn(H2O)4 2+ provides an accelerated charge transfer process and reduces the activation energy for zinc deposition from 40 to 21 kJ mol-1. The PI nanofabric also acts as a protective barrier, reducing side reactions at the electrode. As a result, the PI-Zn symmetric cell exhibits remarkable cycling stability over 1200 h, maintaining a dendrite-free morphology and minimal byproduct formation. Moreover, the cell exhibits high stability and low voltage hysteresis even under high current densities (20 mA cm-2, 10 mAh cm-2) thanks to the 3D porous structure of PI nanofabric. When integrated into full cells, the PI-Zn||AC hybrid zinc-ion capacitor and PI-Zn||MnVOH@SWCNT zinc-ion battery achieve impressive lifespans of 15000 and 600 cycles with outstanding capacitance retention. This approach paves a novel avenue for high-performance zinc metal electrodes.

Hybrid Interface Chemistry Enabling Mixed Conducting via Ultrafast Microwave Polarization Toward Dendrite-Free Zn Anodes.

Zn metal anodes in aqueous electrolytes suffer from interface issues including uncontrolled dendrite growth and undesired side reactions, resulting in their limited application in terms of short circuits and cell failure. Herein, a hybrid interface chemistry strategy is developed through ultrafast microwave polarization at the skin region of bare Zn. Owing to efficient Joule heating directed by abundant local hot spots at electron valleys, the rapid establishment of a dense interfacial layer can be realized within a minute. Stabilized Zn with suppressed side reactions or surface corrosion is therefore achieved due to the interfacial protection. Importantly, hybrid zincophilic sites involving laterally/vertically interconnected Cu-Zn intermetallic compound and Zn2+-conductive oxide species ensure mixed charge conducting (denoted as CuHL@Zn), featuring uniformly distributed electric field and boosted Zn2+ diffusion kinetics. As a consequence, CuHL@Zn in symmetric cells affords lifespans of 2800 and 3200 h with ultra-low polarization voltages (≈19 and 56 mV) at a plating capacity of 1.0 mAh cm-2 for 1 and 5 mA cm-2, respectively. The CuHL@Zn||MnO2 full cell further exhibits cycling stability with a capacity retention of over 80% for 500 cycles at 2 A g-1.

Bottom Deposition Enables Stable All-Solid-State Batteries with Ultrathin Lithium Metal Anode.

Modern strides in energy storage underscore the significance of all-solid-state batteries (ASSBs) predicated on solid electrolytes and lithium (Li) metal anodes in response to the demand for safer batteries. Nonetheless, ASSBs are often beleaguered by non-uniform Li deposition during cycling, leading to compromised cell performance from internal short circuits and hindered charge transfer. In this study, the concept of "bottom deposition" is introduced to stabilize metal deposition based on the lithiophilic current collector and a protective layer composed of a polymeric binder and carbon black. The bottom deposition, wherein Li plating ensues between the protective layer and the current collector, circumvents internal short circuits and facilitates uniform volumetric changes of Li. The prepared functional binder for the protective layer presents outstanding mechanical robustness and adhesive properties, which can withstand the volume expansion caused by metal growth. Furthermore, its excellent ion transfer properties promote uniform Li bottom deposition even under a current density of 6 mA·cm-2. Also, scanning electron microscopy analysis reveals a consistent plating/stripping morphology of Li after cycling. Consequently, the proposed system exhibits enhanced electrochemical performance when assessed within the ASSB framework, operating under a configuration marked by a high Li utilization rate reliant on an ultrathin Li.

Stable Zinc Anode Facilitated by Regenerated Silk Fibroin-modified Hydrogel Protective Layer.

Inherent dendrite growth and side reactions of zinc anode caused by its unstable interface in aqueous electrolytes severely limit the practical applications of zinc-ion batteries (ZIBs). To overcome these challenges, a protective layer for Zn anode inspired by cytomembrane structure is developed with PVA as framework and silk fibroin gel suspension (SFs) as modifier. This PVA/SFs gel-like layer exerts similar to the solid electrolyte interphase, optimizing the anode-electrolyte interface and Zn2+ solvation structure. Through interface improvement, controlled Zn2+ migration/diffusion, and desolvation, this buffer layer effectively inhibits dendrite growth and side reactions. The additional SFs provide functional improvement and better interaction with PVA by abundant functional groups, achieving a robust and durable Zn anode with high reversibility. Thus, the PVA/SFs@Zn symmetric cell exhibits an ultra-long lifespan of 3150 h compared to bare Zn (182 h) at 1.0 mAh cm-2-1.0 mAh cm-2, and excellent reversibility with an average Coulombic efficiency of 99.04% under a large plating capacity for 800 cycles. Moreover, the PVA/SFs@Zn||PANI/CC full cells maintain over 20 000 cycles with over 80% capacity retention under harsh conditions at 5 and 10 A g-1. This SF-modified protective layer for Zn anode suggests a promising strategy for reliable and high-performance ZIBs.

Sustained Release-Driven Interface Engineering Enables Fast Charging Lithium Metal Batteries.

LiNO3 has attracted intensive attention as a promising electrolyte additive to regulate Li deposition behavior as it can form favorable Li3N, LiNxOy species to improve the interfacial stability. However, the inferior solubility in carbonate-based electrolyte restricts its application in high-voltage Li metal batteries. Herein, an artificial composite layer (referred to as PML) composed of LiNO3 and PMMA is rationally designed on Li surface. The PML layer serves as a reservoir for LiNO3 release gradually to the electrolyte during cycling, guaranteeing the stability of SEI layer for uniform Li deposition. The PMMA matrix not only links the nitrogen-containing species for uniform ionic conductivity but also can be coordinated with Li for rapid Li ions migration, resulting in homogenous Li-ion flux and dendrite-free morphology. As a result, stable and dendrite-free plating/stripping behaviors of Li metal anodes are achieved even at an ultrahigh current density of 20 mA cm-2 (>570 h) and large areal capacity of 10 mAh cm-2 (>1200 h). Moreover, the Li||LiFePO4 full cell using PML-Li anode undergoes stable cycling for 2000 cycles with high-capacity retention of 94.8%. This facile strategy will widen the potential application of LiNO3 in carbonate-based electrolyte for practical LMBs.

In Situ Inorganic/Organic Protective Layer on Carbon Paper as Advanced Current Collector for Robust Li Metal Anode.

Lithium (Li) metal is regarded as the most promising anode for next-generation batteries with high energy density. However, the uncontrolled dendrite growth and infinite volume expansion during cycling seriously hinder the application of Li metal batteries (LMBs). Herein, an inorganic/organic protective layer (labeled as BPH), composed of in situ formed inorganic constituents and PVDF-HFP, is designed on the 3D carbon paper (CP) surface by hot-dipping method. The BPH layer can effectively improve the mechanical strength and ionic conductivity of the SEI layer, which is beneficial to expedite the Li-ion transfer of the entire framework and achieve stable Li plating/stripping behavior. As a result, the modified 3D CP (BPH-CP) exhibits an ultrahigh average Coulombic efficiency (CE) of ≈99.7% over 400 cycles. Further, the Li||LiFePO4 (LFP) cell exhibits an extremely long-term cycle life of over 3000 cycles at 5 C. Importantly, the full cell with high mass loading LiFePO4 (20 mg cm-2) or LiNi0.8Co0.1Mn0.1O2 (NCM, 16 mg cm-2) cathode exhibits stable cycling for 100 or 150 cycles at 0.5 C with high-capacity retention of 86.5% or 82.0% even at extremely low N/P ratio of 0.88 or 0.94. believe that this work enlightens a simple and effective strategy for the application of high-energy-density and high-rate-C LMBs.

n-ZrS3/p-ZrOS Photoanodes with NiOOH/FeOOH Oxygen Evolution Catalysts for Photoelectrochemical Water Oxidation.

Photoelectrochemical water splitting offers a promising approach for carbon neutrality, but its commercial prospects are still hampered by a lack of efficient and stable photoelectrodes with earth-abundant materials. Here, we report a strategy to construct an efficient photoanode with a coaxial nanobelt structure, comprising a buried-ZrS3/ZrOS n-p junction, for photoelectrochemical water splitting. The p-type ZrOS layer, formed on the surface of the n-type ZrS3 nanobelt through a pulsed-ozone-treatment method, acts as a hole collection layer for hole extraction and a protective layer to shield the photoanode from photocorrosion. The resulting ZrS3/ZrOS photoanode exhibits light harvesting with good photo-to-current efficiencies across the whole visible region to over 650 nm. By further employing NiOOH/FeOOH as the oxygen evolution reaction cocatalyst, the ZrS3/ZrOS/NiOOH/FeOOH photoanode yields a photocurrent density of ~9.3 mA cm-2 at 1.23 V versus the reversible hydrogen electrode with an applied bias photon-to-current efficiency of ~3.2% under simulated sunlight irradiation in an alkaline solution (pH = 13.6). The conformal ZrOS layer enables ZrS3/ZrOS/NiOOH/FeOOH photoanode operation over 1000 hours in an alkaline solution without obvious performance degradation. This study, offering a promising approach to fabricate efficient and durable photoelectrodes with earth-abundant materials, advances the frontiers of photoelectrochemical water splitting.

Integrating Prelithiation and Interface Protection to Achieve High-Energy All-Solid-State Batteries.

All-solid-state batteries (ASSBs), particularly those with Li-free anodes or even anode-free configurations, have attracted extensive attention due to high safety and energy density. However, chemical-mechanical degradation typically deteriorates the cycle life and energy of Li-free anode ASSBs with the absence of Li inventory. Here, the prelithiation agent Li5FeO4 (LFO) coated Ni-rich layered oxide is developed as the cathode for Li-free anode ASSBs. The coated LFO acts as an interfacial protective layer to prevent the highly oxidizing Ni-rich cathode from reacting with sulfide solid-state electrolytes (SSEs), mitigating the structural degradation of Ni-rich cathodes and the decomposition of SSE, resulting in excellent cycle life. Beneficial from the coated LFO in the cathode of the Li-free anode ASSBs, the reversible capacity improves from 174.7 mAh g-1 to 199.7 mAh g-1, and the capacity retention is enhanced from 33.8% to 84.8% after 100 cycles. Additionally, an ultrahigh energy density of 440 Wh kg-1, based on the mass of the composite cathode, Li-free anode, and SSE, is obtained in a Li-free anode all-solid-state pouch cell equipped with the LFO-coated cathode.

Bipolar Polymeric Protective Layer for Dendrite-Free and Corrosion-Resistant Lithium Metal Anode in Ethylene Carbonate Electrolyte.

The unstable interface between Li metal and ethylene carbonate (EC)-based electrolytes triggers continuous side reactions and uncontrolled dendrite growth, significantly impacting the lifespan of Li metal batteries (LMBs). Herein, a bipolar polymeric protective layer (BPPL) is developed using cyanoethyl (-CH2CH2C≡N) and hydroxyl (-OH) polar groups, aiming to prevent EC-induced corrosion and facilitating rapid, uniform Li+ ion transport. Hydrogen-bonding interactions between -OH and EC facilitates the Li+ desolvation process and effectively traps free EC molecules, thereby eliminating parasitic reactions. Meanwhile, the -CH2CH2C≡N group anchors TFSI- anions through ion-dipole interactions, enhancing Li+ transport and eliminating concentration polarization, ultimately suppressing the growth of Li dendrite. This BPPL enabling Li|Li cell stable cycling over 750 cycles at 10 mA cm-2 for 2 mAh cm-2. The Li|LiNi0.8Mn0.1Co0.1O2 and Li|LiFePO4 full cells display superior electrochemical performance. The BPPL provides a practical strategy to enhanced stability and performance in LMBs application.

SOx Functionalized NiOOH Nanosheets Embedded in Ni(OH)2 Microarray for High-Efficiency Seawater Oxidation.

A nano-micro heterostructure has been established to address the challenges of selectivity, stress, pitting corrosion, and long-term durability of anodes in unpurified seawater. The heterostructure comprised NiOOH nanosheets embedded within a high surface area Ni(OH)2 microarray, and the surface structure is further functionalized with sulfate (SOx ). This cation-selective protective layer impedes chloride (Cl- ) diffusion and abstracts H from reaction intermediates, leading to enhanced selectivity and corrosion resistance of the anode. The multilevel porosity within the randomly oriented nanosheets and the underlying support provide short diffusion channels for ions and mass migration, ensuring efficient ion transport and long-term structural and mechanical durability of the active sites, even at high current density. Remarkably, the catalyst requires a small input voltage of 400 mV to deliver a current density of 1 A cm-2 and maintains it for over 168 h without noticeable degradation or hypochlorite formation. Spectroscopic analysis and density functional theory (DFT) calculations reveal that the Ni electronic structure in the +3 valence state, its strong structural interaction with the underlying microarray, and the functionality of SOx significantly reduce the required potential for O-O coupling.

Effect of Protective Layer on the Performance of Monocrystalline Silicon Cell for Indoor Light Harvesting.

The development of renewable energy sources has grown increasingly as the world shifts toward lowering carbon emissions and supporting sustainability. Solar energy is one of the most promising renewable energy sources, and its harvesting potential has gone beyond typical solar panels to small, portable devices. Also, the trend toward smart buildings is becoming more prevalent at the same time as sensors and small devices are becoming more integrated, and the demand for dependable, sustainable energy sources will increase. Our work aims to tackle the issue of identifying the most suitable protective layer for small optical devices that can efficiently utilize indoor light sources. To conduct our research, we designed and tested a model that allowed us to compare the performance of many small panels made of monocrystalline cells laminated with three different materials: epoxy resin, an ethylene-tetrafluoroethylene copolymer (ETFE), and polyethylene terephthalate (PET), under varying light intensities from LED and CFL sources. The methods employed encompass contact angle measurements of the protective layers, providing insights into their wettability and hydrophobicity, which indicates protective layer performance against humidity. Reflection spectroscopy was used to evaluate the panels' reflectance properties across different wavelengths, which affect the light amount arrived at the solar cell. Furthermore, we characterized the PV panels' electrical behavior by measuring short-circuit current (ISC), open-circuit voltage (VOC), maximum power output (Pmax), fill factor (FF), and load resistance (R). Our findings offer valuable insights into each PV panel's performance and the protective layer material's effect. Panels with ETFE layers exhibited remarkable hydrophobicity with a mean contact angle of 77.7°, indicating resistance against humidity-related effects. Also, panels with ETFE layers consistently outperformed others as they had the highest open circuit voltage (VOC) ranging between 1.63-4.08 V, fill factor (FF) between 35.9-67.3%, and lowest load resistance (R) ranging between 11,268-772 KΩ.cm-2 under diverse light intensities from various light sources, as determined by our results. This makes ETFE panels a promising option for indoor energy harvesting, especially for powering sensors with low power requirements. This information could influence future research in developing energy harvesting solutions, thereby making a valuable contribution to the progress of sustainable energy technology.

Optimizing Stability and Performance of Silver-Based Grating Structures for Surface Plasmon Resonance Sensors.

The use of surface plasmon resonance sensors allows for the fabrication of highly sensitive, label-free analytical devices. This contribution reports on a grating coupler to enable surface plasmon resonance studies using silver on silicon oxide technology to build long-term stable plasmonic structures for biological molecule sensing. The structural parameters were simulated and the corresponding simulation model was optimized based on the experimental results to improve its reliability. Based on the model, optimized grating nanostructures were fabricated on an oxidized silicon wafer with different structural parameters and characterized using a dedicated optical setup and scanning electron microscopy. The combined theoretical and experimental results show that the most relevant refractive index range for biological samples from 1.32-1.46 may conveniently be covered with a highest sensitivity of 128.85°/RIU.

Alleviating Side Reactions on Zn Anodes for Aqueous Batteries by a Cell Membrane Derived Phosphorylcholine Zwitterionic Protective Layer.

Aqueous zinc (Zn) ion batteries are attractive for next generation batteries with high safety, yet their applications are still hindered by the uncontrollable dendrite formation and side reactions on Zn anode. Here, a polyzwitterion protective layer (PZIL) was engineered by polymerizing 2-methacryloyloxyethyl phosphorylcholine (MPC) in carboxymethyl chitosan (CMCS), which renders the following merits: the choline groups of MPC can preferentially adsorb onto Zn metal to avoid side reactions; the charged phosphate groups chelate with Zn2+ to regulate the solvation structure, further improving side reaction inhibition; the Hofmeister effect between ZnSO4 and CMCS can enhance the interfacial contact during electrochemical characterization. Consequently, the symmetrical Zn battery with PZIL can keep stable for more than 1000 hours under the ultra-high current density of 40 mA cm-2 . The PZIL confers the Zn/MnO2 full battery and Zn/active carbon (AC) capacitor with stable cycling performance under high current density.

Revealing the Two-Dimensional Surface Diffusion Mechanism for Zinc Dendrite Formation on Zinc Anode.

Aqueous zinc-ion battery is regarded as one of the promising devices for large-scale energy storage systems owing to its high safety, cost-effectiveness, and competitive electrochemical properties. However, the dendrite growth on zinc metal anodes dramatically hinders its further practical applications, and the internal mechanism of dendrite evolution is still unclear. The introduction of a protective layer on the anode interface is an effective method to avoid zinc dendrite growth. Herein, a two-dimensional (2D) atomic surface diffusion mechanism is proposed to reveal the evolution of zinc deposition from tiny protrusion to dendrite under uneven electric and ionic fields. Further, the conductive copper nitride (CN) protective layer is constructed on the zinc metal anode by a facile and scalable magnetron sputtering approach. Their protective layer possesses a high zinc affinity and high diffusion barrier for zinc atom migration, leading to spacious nucleation, and uniform zinc deposition, thus significantly boosting the electrochemical stability. For the first time, the role of the restricted 2D atomic surface diffusion mechanism in inhibiting the formation of zinc tiny protrusion that induces uneven electric and ionic fields is revealed. This work can provide a novel insight for future research on dendrite-free zinc metal anodes by interfacial modification.

Inhibiting corrosion and side reactions of zinc metal anode by nano-CaSiO3coating towards high-performance aqueous zinc-ion batteries.

The aqueous Zn-ion batteries (AZIBs) have been deemed as one of the most promising energy storage devices owing to their high safety, low cost, and environmental benignity. Nevertheless, the severe corrosion of zinc metal anode and side reactions between the anode and electrolyte greatly hinder the practical application of AZIBs. To address above-mentioned issues, herein, a nano-CaSiO3layer was coated on the surface of Zn metal anode via the solution casting method. Results showed that this hydrophobic coating layer could effectively inhibit the direct contact of Zn metal anode with electrolyte, suppressing its corrosion and side reactions during Zn deposition/stripping. When applied in symmetrical cells, the nano-CaSiO3coated Zn (CSO-Zn) electrode exhibited much longer cycle life than bare Zn electrode. Moreover, with this nano-CaSiO3modified Zn anode, both vanadium-based and manganese-based full cells depicted excellent capacity retention. This nano-CaSiO3coating layer provides a good choice for improving the stability of Zn metal anode for high-performance AZIBs.

A Rigid-Flexible Protecting Film with Surface Pits Structure for Dendrite-Free and High-Performance Lithium Metal Anode.

An artificial organic/inorganic composite protecting film for lithium metal anode with one-side surface pits structure was prepared by poly(vinylidene fluoride-co-hexafluoropropylene) and Al2O3+LiNO3 inorganic additives. Due to the unique surface structure, the composite film can not only serve as an artificial protective film, but also act as an additional lithium plating host, which synergistically enabled the lithium metal anode to adapt to high current densities meanwhile maintain dendrite-free during long-term cycling. As a result, the protected lithium metal anode can operate stably for 1000 h at a high current density of 10.0 mA cm-2. When paired with a LiFePO4 or sulfur cathode, the full cells with unflooded electrolyte showed significantly improved cycling performance, demonstrating great potential of this artificial protecting film in lithium metal batteries.

Ultra-Fast and Scalable Saline Immersion Strategy Enabling Uniform Zn Nucleation and Deposition for High-Performance Zn-Ion Batteries.

Although aqueous Zn-ion batteries (ZIBs) with low cost and high safety show great potential in large-scale energy storage system, metallic Zn anode still suffers from unsatisfactory cycle stability due to unregulated growth of Zn dendrites, corrosion, and formation of various side products during electrochemical reaction. Here, an ultrafast and simple method to achieve a stable Zn anode is developed. By simply immersing a Zn plate into an aqueous solution of CuSO4 for only 10-60 s, a uniform and robust protective layer (Zn4 SO4 (OH)6 ·5H2 O/Cu2 O) is formed on commercial Zn plate (Zn/ZCO), which enables uniform electric field distribution and controllable dendrite growth, leading to a long-term cycle life of over 1400 h and high average Coulombic efficiency (CE) of 99.2% at 2.0 mA cm-2 and 2.0 mAh cm-2 . These excellent characteristics of the prepared Zn anode show great potential in practical applications for high-performance aqueous Zn-ion batteries.

Role of TiO2coating layer on the performance of Cu2O photocathode in photoelectrochemical CO2reduction.

TiO2is usually employed as a protective layer for Cu2O in photoelectrocatalytic CO2reduction. However, the role of TiO2layer on CO2reduction activity and selectivity is still elusive. In this work, a systematic investigation is carried out to probe the impact of the deposition parameters of TiO2overlayer, including the temperature and thickness, on CO2reduction performance. Compositional and (photo-)electrochemical analysis is performed to explore the property of TiO2overlayers. Carrier behavior, including donor density and electron energy, and stability of TiO2are demonstrated to be influenced by atomic layer deposition conditions and thus play a role in controlling CO2reduction reaction. Specifically, as the thickness of the TiO2layer increases from 2 to 50 nm, the electron energy tends to be lowered accompanying the electron transfer mode from tunneling for TiO2thin layers to type II for thick TiO2, leading to a decrease in CO2reduction selectivity. With an increase of the TiO2deposition temperature, the stability increases with a loss of conductivity. Cu2O coated with 2 nm TiO2at 150 °C is proven to be the optimized candidate in this work for photoelectrochemical reduction of CO2to CO, HCOOH and CH3COOH under an applied bias of -0.4 versus RHE.