
Riley Zhang
Ph.D. Student in Materials Science and Engineering, admitted Autumn 2019
public speaking tutor, School of Engineering - Technical Communications Program
Bio
Pu Riley Zhang is a materials science grad student, advised by Dr. Yi Cui and Dr. Johanna Nelson Weker. She focuses on self-discharge behaviors of lithium-sulfur batteries, chemical corrosion of lithium, and scaleable alkaline water electrolysis. She received her BS in NanoEngineering from UC San Diego in 2019, where she was advised by Dr. Zheng Chen on synthesizing PtIr nanocatalysts for Ethanol Oxidation and Pd nanocrystals for Oxygen Reduction Reaction.
Contact: puzhang AT stanford.edu
All Publications
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LiI-Modified Glass-Ceramic Lithium Thioborate: From Fundamentals to Applications in Solid-State Batteries
CHEMISTRY OF MATERIALS
2025
View details for DOI 10.1021/acs.chemmater.5c00224
View details for Web of Science ID 001453766500001
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Asymmetric ether solvents for high-rate lithium metal batteries
NATURE ENERGY
2025
View details for DOI 10.1038/s41560-025-01716-w
View details for Web of Science ID 001421539700001
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Crowding Agent Stabilizes Aqueous Electrolyte for Reversible Iron Metal Anode
ACS ENERGY LETTERS
2025
View details for DOI 10.1021/acsenergylett.4c03268
View details for Web of Science ID 001412253100001
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Epitaxial Electrodeposition of Zinc on Different Single Crystal Copper Substrates for High Performance Aqueous Batteries.
Nano letters
2025
Abstract
The aqueous zinc metal battery holds great potential for large-scale energy storage due to its safety, low cost, and high theoretical capacity. However, challenges such as corrosion and dendritic growth necessitate controlled zinc deposition. This study employs epitaxy to achieve large-area, dense, and ultraflat zinc plating on textured copper foil. High-quality copper foils with Cu(100), Cu(110), and Cu(111) facets were prepared and systematically compared. The results show that Cu(111) is the most favorable for zinc deposition, offering the lowest nucleation overpotential, diffusion energy, and interfacial energy with a Coulombic efficiency (CE) of 99.93%. The study sets a record for flat-zinc areal loading at 20 mAh/cm2. These findings provide some clarity on the best-performing copper and zinc crystalline facets, with Cu(111)/Zn(0002) ranking the highest. Using a MnO2-Zn full cell model, the research achieved an exceptional cycle life of over 800 cycles in a cathode-anode-free battery configuration.
View details for DOI 10.1021/acs.nanolett.4c04535
View details for PubMedID 39835735
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Continuous lithium extraction from brine by efficient redox-couple electrodialysis
MATTER
2024; 7 (11)
View details for DOI 10.1016/j.matt.2024.07.014
View details for Web of Science ID 001353962000001
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Capacity recovery by transient voltage pulse in silicon-anode batteries.
Science (New York, N.Y.)
2024; 386 (6719): 322-327
Abstract
In the quest for high-capacity battery electrodes, addressing capacity loss attributed to isolated active materials remains a challenge. We developed an approach to substantially recover the isolated active materials in silicon electrodes and used a voltage pulse to reconnect the isolated lithium-silicon (LixSi) particles back to the conductive network. Using a 5-second pulse, we achieved >30% of capacity recovery in both Li-Si and Si-lithium iron phosphate (Si-LFP) batteries. The recovered capacity sustains and replicates through multiple pulses, providing a constant capacity advantage. We validated the recovery mechanism as the movement of the neutral isolated LixSi particles under a localized nonuniform electric field, a phenomenon known as dielectrophoresis.
View details for DOI 10.1126/science.adn1749
View details for PubMedID 39418354
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In situ formation of liquid crystal interphase in electrolytes with soft templating effects for aqueous dual-electrode-free batteries
NATURE ENERGY
2024
View details for DOI 10.1038/s41560-024-01638-z
View details for Web of Science ID 001317361000002
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Lithiophilic Hydrogen-Substituted Graphdiyne Aerogels with Ionically Conductive Channels for High-Performance Lithium Metal Batteries.
Nano letters
2024
Abstract
Lithium (Li) metal stands as a promising anode in advancing high-energy-density batteries. However, intrinsic issues associated with metallic Li, especially the dendritic growth, have hindered its practical application. Herein, we focus on molecular combined structural design to develop dendrite-free anodes. Specifically, using hydrogen-substituted graphdiyne (HGDY) aerogel hosts, we successfully fabricated a promising Li composite anode (Li@HGDY). The HGDY aerogel's lithiophilic nature and hierarchical pores drive molten Li infusion and reduce local current density within the three-dimensional HGDY host. The unique molecular structure of HGDY provides favorable bulk pathways for lithium-ion transport. By simultaneous regulation of electron and ion transport within the HGDY host, uniform lithium stripping/platting is fulfilled. Li@HGDY symmetric cells exhibit a low overpotential and stable cycling. The Li@HGDY||lithium iron phosphate full cell retained 98.1% capacity after 170 cycles at 0.4 C. This study sheds new light on designing high-capacity and long-lasting lithium metal anodes.
View details for DOI 10.1021/acs.nanolett.3c04370
View details for PubMedID 38437632
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Electrolytes with moderate lithium polysulfide solubility for high-performance long-calendar-life lithium-sulfur batteries.
Proceedings of the National Academy of Sciences of the United States of America
2023; 120 (31): e2301260120
Abstract
Lithium-sulfur (Li-S) batteries with high energy density and low cost are promising for next-generation energy storage. However, their cycling stability is plagued by the high solubility of lithium polysulfide (LiPS) intermediates, causing fast capacity decay and severe self-discharge. Exploring electrolytes with low LiPS solubility has shown promising results toward addressing these challenges. However, here, we report that electrolytes with moderate LiPS solubility are more effective for simultaneously limiting the shuttling effect and achieving good Li-S reaction kinetics. We explored a range of solubility from 37 to 1,100 mM (based on S atom, [S]) and found that a moderate solubility from 50 to 200 mM [S] performed the best. Using a series of electrolyte solvents with various degrees of fluorination, we formulated the Single-Solvent, Single-Salt, Standard Salt concentration with Moderate LiPSs solubility Electrolytes (termed S6MILE) for Li-S batteries. Among the designed electrolytes, Li-S cells using fluorinated-1,2-diethoxyethane S6MILE (F4DEE-S6MILE) showed the highest capacity of 1,160 mAh g-1 at 0.05 C at room temperature. At 60 °C, fluorinated-1,4-dimethoxybutane S6MILE (F4DMB-S6MILE) gave the highest capacity of 1,526 mAh g-1 at 0.05 C and an average CE of 99.89% for 150 cycles at 0.2 C under lean electrolyte conditions. This is a fivefold increase in cycle life compared with other conventional ether-based electrolytes. Moreover, we observed a long calendar aging life, with a capacity increase/recovery of 4.3% after resting for 30 d using F4DMB-S6MILE. Furthermore, the correlation between LiPS solubility, degree of fluorination of the electrolyte solvent, and battery performance was systematically investigated.
View details for DOI 10.1073/pnas.2301260120
View details for PubMedID 37487097
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High-entropy electrolytes for practical lithium metal batteries
NATURE ENERGY
2023
View details for DOI 10.1038/s41560-023-01280-1
View details for Web of Science ID 001023405800005
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Ni Anchored to Hydrogen-Substituted Graphdiyne for Lithium Sulfide Cathodes in Lithium-Sulfur Batteries.
Nano letters
2023
Abstract
Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage systems due to their high theoretical energy density and the low cost of sulfur. However, slow conversion kinetics between the insulating S and lithium sulfide (Li2S) remains as a technical challenge. In this work, we report a catalyst featuring nickel (Ni) single atoms and clusters anchored to a porous hydrogen-substituted graphdiyne support (termed Ni@HGDY), which is incorporated in Li2S cathodes. The rapidly synthesized catalyst was found to enhance ionic and electronic conductivity, decrease the reaction overpotential, and promote more complete conversion between Li2S and sulfur. The addition of Ni@HGDY to commercial Li2S powder enabled a capacity of over 516 mAh gLi2S-1 at 1 C for over 125 cycles, whereas the control Li2S cathode managed to maintain just over 200 mAh gLi2S-1. These findings highlight the efficacy of Ni as a metal catalyst and demonstrate the promise of HGDY in energy storage devices.
View details for DOI 10.1021/acs.nanolett.3c01034
View details for PubMedID 37350461
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In Situ Prelithiation by Direct Integration of Lithium Mesh into Battery Cells.
Nano letters
2023
Abstract
Silicon (Si)-based anodes are promising for next-generation lithium (Li)-ion batteries due to their high theoretical capacity (3600 mAh/g). However, they suffer quantities of capacity loss in the first cycle from initial solid electrolyte interphase (SEI) formation. Here, we present an in situ prelithiation method to directly integrate a Li metal mesh into the cell assembly. A series of Li meshes are designed as prelithiation reagents, which are applied to the Si anode in battery fabrication and spontaneously prelithiate Si with electrolyte addition. Various porosities of Li meshes tune prelithiation amounts to control the degree of prelithiation precisely. Besides, the patterned mesh design enhances the uniformity of prelithiation. With an optimized prelithiation amount, the in situ prelithiated Si-based full cell shows a constant >30% capacity improvement in 150 cycles. This work presents a facile prelithiation approach to improve battery performance.
View details for DOI 10.1021/acs.nanolett.3c00859
View details for PubMedID 37236151
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Experimental Discovery of a Fast and Stable Lithium Thioborate Solid Electrolyte, Li6+2x [B10S18]S- x (x approximate to 1)
ACS ENERGY LETTERS
2023; 8 (6): 2762-2771
View details for DOI 10.1021/acsenergylett.3c00560
View details for Web of Science ID 001005978800001
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Ultrahigh-loading Manganese-based Electrode for Aqueous Battery via Polymorph Tuning.
Advanced materials (Deerfield Beach, Fla.)
2023: e2211555
Abstract
Manganese-based aqueous batteries utilizing Mn2+ /MnO2 redox reactions are promising choices for grid-scale energy storage due to their high theoretical specific capacity, high power capability, low-cost, and intrinsic safety with water-based electrolytes. However, the application of such systems is hindered by the insulating nature of deposited MnO2 , resulting in low normalized areal loading (0.0050.05 mAh cm-2 ) during charge/discharge cycle. In this work, we investigated the electrochemical performance of various MnO2 polymorphs in Mn2+ /MnO2 redox reactions and determined ɛ-MnO2 with low conductivity to be the primary electrochemically deposited phase in normal acidic aqueous electrolyte. We found that increasing the temperature can change the deposited phase from ɛ-MnO2 with low conductivity to gamma-MnO2 with two orders of magnitude increase in conductivity. We demonstrated that the highly conductive gamma-MnO2 could be effectively exploited for ultrahigh areal loading electrode, and a normalized areal loading of 33 mAh cm-2 was achieved. At a mild temperature of 50 °C, cells were cycled with an ultrahigh areal loading of 20 mAh cm-2 (1-2 orders of magnitude higher than previous studies) for over 200 cycles with only 13% capacity loss. This article is protected by copyright. All rights reserved.
View details for DOI 10.1002/adma.202211555
View details for PubMedID 37149287
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Hydrogen-substituted graphdiyne-assisted ultrafast sparking synthesis of metastable nanomaterials.
Nature nanotechnology
2022
Abstract
Metastable nanomaterials, such as single-atom and high-entropy systems, with exciting physical and chemical properties are increasingly important for next-generation technologies. Here, we developed a hydrogen-substituted graphdiyne-assisted ultrafast sparking synthesis (GAUSS) platform for the preparation of metastable nanomaterials. The GAUSS platform can reach an ultra-high reaction temperature of 3,286K within 8ms, a rate exceeding 105Ks-1. Controlling the composition and chemistry of the hydrogen-substituted graphdiyne aerogel framework, the reaction temperature can be tuned from 1,640 K to 3,286K. We demonstrate the versatility of the GAUSS platform with the successful synthesis of single atoms, high-entropy alloys and high-entropy oxides. Electrochemical measurements and density functional theory show that single atoms synthesized by GAUSS enhance the lithium-sulfur redox reaction kinetics in all-solid-state lithium-sulfur batteries. Our design of the GAUSS platform offers a powerful way to synthesize a variety of metastable nanomaterials.
View details for DOI 10.1038/s41565-022-01272-4
View details for PubMedID 36585516
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An Interdigitated Li-Solid Polymer Electrolyte Framework for Interfacial Stable All-Solid-State Batteries
ADVANCED ENERGY MATERIALS
2022
View details for DOI 10.1002/aenm.202201160
View details for Web of Science ID 000843752000001
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All-Solid-State Lithium-Sulfur Batteries Enhanced by Redox Mediators.
Journal of the American Chemical Society
2021
Abstract
Redox mediators (RMs) play a vital role in some liquid electrolyte-based electrochemical energy storage systems. However, the concept of redox mediator in solid-state batteries remains unexplored. Here, we selected a group of RM candidates and investigated their behaviors and roles in all-solid-state lithium-sulfur batteries (ASSLSBs). The soluble-type quinone-based RM (AQT) shows the most favorable redox potential and the best redox reversibility that functions well for lithium sulfide (Li2S) oxidation in solid polymer electrolytes. Accordingly, Li2S cathodes with AQT RMs present a significantly reduced energy barrier (average oxidation potential of 2.4 V) during initial charging at 0.1 C at 60 °C and the following discharge capacity of 1133 mAh gs-1. Using operando sulfur K-edge X-ray absorption spectroscopy, we directly tracked the sulfur speciation in ASSLSBs and proved that the solid-polysulfide-solid reaction of Li2S cathodes with RMs facilitated Li2S oxidation. In contrast, for bare Li2S cathodes, the solid-solid Li2S-sulfur direct conversion in the first charge cycle results in a high energy barrier for activation (charge to 4 V) and low sulfur utilization. The Li2S@AQT cell demonstrates superior cycling stability (average Coulombic efficiency 98.9% for 150 cycles) and rate capability owing to the effective AQT-enhanced Li-S reaction kinetics. This work reveals the evolution of sulfur species in ASSLSBs and realizes the fast Li-S reaction kinetics by designing an effective sulfur speciation pathway.
View details for DOI 10.1021/jacs.1c07754
View details for PubMedID 34677957
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Synthesis of pomegranate-shaped micron ZnMn2O4 with enhanced lithium storage capability
JOURNAL OF MATERIOMICS
2021; 7 (4): 699-707
View details for DOI 10.1016/j.jmat.2021.01.005
View details for Web of Science ID 000651461800006
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In-situ hydrothermal synthesis of delta-MnO2/soybean pod carbon and its high performance application on supercapacitor
JOURNAL OF ALLOYS AND COMPOUNDS
2021; 853
View details for DOI 10.1016/j.jallcom.2020.157357
View details for Web of Science ID 000582806400149
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Wheat Bran Derived Carbon toward Cost-Efficient and High Performance Lithium Storage
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
2020; 8 (42): 15898–905
View details for DOI 10.1021/acssuschemeng.0c04670
View details for Web of Science ID 000586722300011
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Synthesis of natural nitrogen-rich soybean pod carbon with ion channels for low cost and large areal capacitance supercapacitor
APPLIED SURFACE SCIENCE
2020; 516
View details for DOI 10.1016/j.apsusc.2020.146162
View details for Web of Science ID 000539643600006
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Incorporating the nanoscale encapsulation concept from liquid electrolytes into solid-state lithium-sulfur batteries.
Nano letters
2020
Abstract
Lithium-sulfur (Li-S) batteries are attractive due to their high specific energy and low-cost prospect. Most studies in the past decade are based on these batteries with liquid electrolytes, where many exciting material/structural designs are realized at the nanoscale to address problems of Li-S chemistry. Recently, there is a new promising direction to develop Li-S batteries with solid polymer electrolytes, although it is unclear whether the concepts from liquid electrolytes are applicable in the solid state to improve battery performance. Here we demonstrate that the nanoscale encapsulation concept based on Li2S-TiS2 core-shell particles, originally developed in liquid electrolytes, is very effective in solid polymer electrolytes. Using in situ optical cell measurement and sulfur K-edge X-ray absorption near edge spectroscopy, we find that polysulfides form and are well trapped inside individual particles by the nanoscale TiS2 encapsulation. This TiS2 encapsulation layer also functions to catalyze the oxidation reaction of Li2S to sulfur, even in solid-state electrolytes, proved by both experiments and density functional theory calculations. A high cell-level specific energy of 427 W∙h∙kg-1 at 60 °C (including the mass of the anode, cathode, and solid-state electrolyte, but excluding the current collector and packaging) is achieved by integrating TiS2 encapsulated Li2S cathode with ultrathin polyethylene oxide-based solid polymer electrolyte (10~20 m) and lithium metal anode. The solid-state cells show excellent stability over 150 charge/discharge cycles at 0.8 C at 80 °C. This study points to the fruitful direction of borrowing concepts from liquid electrolytes into solid-state Li-S batteries.
View details for DOI 10.1021/acs.nanolett.0c02033
View details for PubMedID 32515973
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Promoting H2O2 production via 2-electron oxygen reduction by coordinating partially oxidized Pd with defect carbon.
Nature communications
2020; 11 (1): 2178
Abstract
Electrochemical synthesis of H2O2 through a selective two-electron (2e-) oxygen reduction reaction (ORR) is an attractive alternative to the industrial anthraquinone oxidation method, as it allows decentralized H2O2 production. Herein, we report that the synergistic interaction between partially oxidized palladium (Pdδ+) and oxygen-functionalized carbon can promote 2e- ORR in acidic electrolytes. An electrocatalyst synthesized by solution deposition of amorphous Pdδ+ clusters (Pd3δ+ and Pd4δ+) onto mildly oxidized carbon nanotubes (Pdδ+-OCNT) shows nearly 100% selectivity toward H2O2 and a positive shift of ORR onset potential by ~320 mV compared with the OCNT substrate. A high mass activity (1.946 A mg-1 at 0.45 V) of Pdδ+-OCNT is achieved. Extended X-ray absorption fine structure characterization and density functional theory calculations suggest that the interaction between Pd clusters and the nearby oxygen-containing functional groups is key for the high selectivity and activity for 2e- ORR.
View details for DOI 10.1038/s41467-020-15843-3
View details for PubMedID 32358548
View details for PubMedCentralID PMC7195490
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Production of activated carbons from four wastes via one-step activation and their applications in Pb2+ adsorption: Insight of ash content.
Chemosphere
2019; 245: 125587
Abstract
Natural biomass is a renewable source for precursors of porous carbon. Four agriculture wastes of corn cob (CC), wheat bran (WB), rice husk (RH), and soybean shell (SS) were applied to produce activated carbons (ACs) via one-step activation by sodium hydroxide. The effects of ash contents and NaOH dosage ratio (1-5) on surface area for ACs were investigated. Owing to ash etching, the high ash precursor (like RH) exhibited less alkali consumption and larger surface area than low ash one (like CC). All four ACs expressed developed pore structure and outstanding surface area of 2500m2g-1. During adsorption of lead ions in simulated wastewater, RH-based AC revealed superior capture capacity of 492±15mgg-1. One-step activation had the potential to deliver savings around 1/3 of energy consumption, enabling the cost performance of high ash RH-based AC reaching 194±12gPb2+$-1, 76% larger than low ash CC-based AC. High ash biomass is a promising candidate to obtain eco-friendly carbon products.
View details for DOI 10.1016/j.chemosphere.2019.125587
View details for PubMedID 31864062
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Enhancing C–C Bond Scission for Efficient Ethanol Oxidation using PtIr Nanocube Electrocatalysts
ACS Catalysis
2019
View details for DOI 10.1021/acscatal.9b02039